KR102474942B1 - Composite for hydrogen-generating catalyst having metal-organic framework and method of preparing the same - Google Patents

Abstract

The present invention relates to a body portion including a first transition metal and a metal-organic framework (MOF); and a plurality of primary particles provided on an outer surface of the body and including a second transition metal.

Description

Composite for hydrogen-generating catalyst having metal-organic framework and method of preparing the same}

The present invention relates to a composite for a hydrogen generation catalyst comprising a metal organic framework and a method for preparing the same, and more particularly, to a hydrogen generation catalyst comprising a metal organic framework capable of replacing a platinum catalyst with low cost and high efficiency. It relates to a complex for use and a method for preparing the same.

The use of fossil fuels has caused climate change, and various studies are being conducted to provide alternative energy sources. Among these alternative energies, energy using hydrogen is applied in various countries around the world due to characteristics such as high energy efficiency and low emission and regeneration of side reactants.

As a method for producing hydrogen, various methods such as water splitting, gasification using biomass, cryogenic distillation, and reforming of fossil fuels have been studied. Among them, water electrolysis is one of the easiest methods to produce almost pure hydrogen, but a catalyst is required to increase the current density and reaction rate in electrolysis.

Platinum is the best material for electrode manufacturing in hydrogen evolution reaction (HER), but its high cost limits its industrial application. Therefore, low-cost catalysts including transition metal dichalcogenides (TMDs), non-noble metals, metal organic frameworks (MOFs) and MXenes are being studied to cope with Pt catalysts in HER.

(prior patent)

Japanese Patent Laid-Open No. 2018-531780 (2018.11.01)

An object of the present invention is to provide a composite for a hydrogen generation catalyst comprising a metal organic skeleton capable of replacing a platinum catalyst and capable of generating hydrogen with high efficiency at a low cost in the process of generating hydrogen using water splitting, and a method for producing the same. it is for

In addition, another object of the present invention is to provide a composite for a hydrogen generation catalyst comprising a metal organic framework prepared in a novel manner and a method for preparing the same.

According to one aspect of the present invention, embodiments of the present invention include a composite for a hydrogen generating catalyst and a method for preparing the composite for a hydrogen generating catalyst.

In one embodiment, the body portion including the first transition metal and a metal-organic framework (MOF); and a plurality of primary particles provided on an outer surface of the body and including a second transition metal.

In one embodiment, the metal organic framework may be MOF-74-based, and the first transition metal may include nickel (Ni) or cobalt (Co).

In one embodiment, the second transition metal may be made of a different metal from the first transition metal.

In one embodiment, the first transition metal may include nickel (Ni) or cobalt (Co), and the second transition metal may include molybdenum (Mo) or tungsten (W).

In one embodiment, the primary particles include MoS _x , and the primary particles are provided to cover the outer surface of the body portion, and at least a portion of the body portion may be provided to be exposed to the outside.

In one embodiment, the primary particles may be provided in 20 parts by weight to 60 parts by weight based on 100 parts by weight of the body part.

In one embodiment, the body portion may have crystal planes (2 -1 0) and (3 0 0) measured by XRD spectrum, and the primary particle may have an amorphous structure.

In one embodiment, when the first transition metal is cobalt (Co), the shape of the body is provided in a rod shape, and when the first transition metal is nickel (Ni), the shape of the body is It is provided as secondary particles formed by aggregation of a plurality of rod-shaped primary particles, and the primary particles are nanoparticles that are vertically anchored on the outer surface of the body portion.

In one embodiment, the onset potential by linear sweep voltammetry (LSV) is -280mV to -140mV when the first transition metal is Co, and 100mV to -140mV when the first transition metal is Ni. 350 mV may be included.

In one embodiment, the first transition metal is Co or Ni, the second transition metal is Mo, and the composite for hydrogen generation catalyst may include 5wt% to 40wt% of CoMoS or NiMoS phase.

In one embodiment, the body portion may have a specific surface area of 300 m2/g to 500 m2/g.

In one embodiment, preparing a body portion by reacting for a first temperature and a first time using a first solution containing a first transition metal; The body part is mixed with a second solution containing a second transition metal, and a third solution is added to react for a second temperature and a second time period to form a plurality of primary particles containing the second transition metal on the outer surface of the body part. coating; wherein the metal organic framework is MOF-74-based, and the first transition metal is nickel (Ni) or cobalt (Co); and a method for producing a composite for hydrogen generation catalyst comprising .

In one embodiment, the first solution is Co(NO ₃ ) ₂ .6H ₂ O or Ni(NO ₃ ) ₂ .6H ₂ O, the first temperature is 80 °C to 120 °C, and the first time is 20 to 30 hours, the second solution is (NH ₄ ) ₂ MoS ₄ , the third solution is hydrazine hydrate, the second temperature is 200 ° C to 300 ° C, and the second time is 8 hours to 15 hours.

According to the present invention as described above, it is possible to provide a composite for a hydrogen generation catalyst comprising an organic metal skeleton capable of coping with expensive platinum used in water decomposition and a method for preparing the same.

In addition, according to the present invention, it is possible to provide a composite for a hydrogen generation catalyst comprising a metal organic framework having a high yield at low cost and a method for preparing the same.

1a and 1b are views schematically showing the shape of a composite for a catalyst for generating hydrogen according to an embodiment of the present invention.
1c is a diagram schematically showing how hydrogen is generated by the complex for a catalyst for hydrogen generation according to the present invention.
Figure 2a is a view schematically showing a method for preparing the MoS _x /Co-MOF-74 composite.
Figure 2b is a view schematically showing a method for preparing the MoS _x /Ni-MOF-74 composite.
Figure 3a is a powder XRD spectrum of 40% MoS _x /Co-MOF-74.
Figure 3b is the FT-IR spectrum of Co-MOF-74.
Figure 3c is a graph showing nitrogen adsorption and desorption of Co-MOF-74 and 40% MoS _x /Co-MOF-74.
4 shows (a) Co-MOF-74, (b) 20% MoS _x /Co-MOF-74, (c) 40% MoS _x /Co-MOF-74, (d) 60% MoS _x /Co- SEM images of MOF-74, (e) 80% MoS _x /Co-MOF-74, and (f) MoS _x .
5 is TEM images of (a) and (d) Co-MOF-74, (b) and (e) MoS _x , (c) and (f) 40% MoS _x /Co-MOF-74, respectively.
Figure 6 is the XPS spectrum of Co-MOF-74 and 40% MoS _x /Co-MOF-74, (a) is Co 2 p, (b) is Mo 3 d and S 2 s, (c) is S 2 p is shown respectively.
Figure 7 shows (a) polarization curve, (b) Tafel slope, (c) EIS Nyquist plot of Co-MOF-74 and 20-100% MoS _x /Co-MOF-74 , (d) C _d and 40% MoS _x /Co-MOF-74 (e) cycle test after 1000 cycles, (f) a graph showing a chronoamperometric curve at a fixed potential of 0.197 V.
8A is a powder XRD spectrum of 40% MoS _x /Ni-MOF-74.
8b is the FT-IR spectrum of Ni-MOF-74.
8C is a graph showing nitrogen adsorption and desorption of Ni-MOF-74 and 40% MoS _x /Ni-MOF-74.
9 shows (a) Ni-MOF-74, (b) 20% MoS _x /Ni-MOF-74, (c) 40% MoS _x /Ni-MOF-74, (d) 60% MoS _x /Ni- SEM images of MOF-74, (e) 80% MoS _x /Ni-MOF-74, and (f) MoS _x .
10 is TEM images of (a) and (d) Ni-MOF-74, (b) and (e) MoS _x , (c) and (f) 40% MoS _x /Ni-MOF-74, respectively.
Figure 11 is the XPS spectrum of Ni-MOF-74 and 40% MoS _x /Ni-MOF-74, (a) Ni 2p , (b) Mo 3 d and S 2 s, (c) is S 2 p is shown respectively.
Figure 12 shows (a) polarization curve, (b) Tafel slope, (c) EIS Nyquist plot of Ni-MOF-74 and 20-100% MoS _x /Ni-MOF-74 , (d) a graph showing a cycle test after 2000 cycles of 40% MoS _x /Ni-MOF-74.

Details of other embodiments are included in the detailed description and drawings.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and unless otherwise specified in the following description, components, reaction conditions, and content of components are expressed in the present invention. All numbers, values and/or expressions are to be understood as being qualified in all cases by the term "about" as such numbers are inherently approximations that reflect, among other things, various uncertainties of measurement that arise in obtaining such values. . Also, when numerical ranges are disclosed herein, such ranges are contiguous and include all values from the minimum value of such range to the maximum value inclusive, unless otherwise indicated. Furthermore, where such a range refers to an integer, all integers inclusive from the minimum value to the maximum value inclusive are included unless otherwise indicated.

Further, in the present invention, where ranges are stated for a variable, it will be understood that the variable includes all values within the stated range inclusive of the stated endpoints of the range. For example, a range of "5 to 10" includes values of 5, 6, 7, 8, 9, and 10, as well as any subrange of 6 to 10, 7 to 10, 6 to 9, 7 to 9, and the like. inclusive, as well as any value between integers that fall within the scope of the stated range, such as 5.5, 6.5, 7.5, 5.5 to 8.5 and 6.5 to 9, and the like. For example, the range of “10% to 30%” could range from 10% to 15%, 12% to 18%, as well as values such as 10%, 11%, 12%, 13%, and all integers up to and including 30%. %, 20% to 30%, etc., and any value between reasonable integers within the scope of the stated range, such as 10.5%, 15.5%, 25.5%, etc. It will be understood to include.

1a and 1b are views schematically showing the shape of a composite for a catalyst for generating hydrogen according to an embodiment of the present invention. 1c is a diagram schematically showing how hydrogen is generated by the complex for a catalyst for hydrogen generation according to the present invention.

An embodiment of the present invention is a body portion including a first transition metal and a metal-organic framework (MOF); and a plurality of primary particles provided on an outer surface of the body and including a second transition metal. The body portion may include a crystalline structure, and the primary particles may be amorphous nano-sized particles. Also, the second transition metal may be formed of a metal different from that of the first transition metal. The composite for a catalyst for hydrogen generation may include a 3-dimensional body and nanoparticle-type primary particles so as to have a 3-dimensional structure.

The metal organic framework may be MOF-74-based, and the first transition metal may include nickel (Ni) or cobalt (Co). Specifically, the first transition metal may include nickel (Ni) or cobalt (Co), and the second transition metal may include molybdenum (Mo) or tungsten (W). At this time, the second transition metal is MoS _x or It may be provided in the form of a sulfur compound of WS _x .

The primary particles may include MoS _x , and the primary particles may be provided to cover an outer surface of the body, and at least a portion of the body may be exposed to the outside.

G_H)의 계산은 수소생성에서 베어(bare) MoS₂보다는 Co-도핑 MoS₂ 및 Fe-도핑 MoS₂이 더 우수하다. 또한, Co, Ni, Fe 이온이 MoS₃ 필름 성장을 촉진시켜, 표면적을 증가시키고 이에 의하여 수소생성 성능을 향상시킬 수 있다. TiO₂ 나노튜브 어레이에 전착된 MoS_xCo_y는 Mo-S-Co 결합을 형성하여 활성중심(불포화 Mo 및 S 자리)의 형성을 향상시키고, HER에서 MoS_x에서 전기촉매 활성을 향성시킨다. 이는 CoMoS 상이 형성되어, MoS₂의 S-에지에서의 R_ct 및

G_H가 감소되었기 때문으로, HER 수율의 향상은 구조 내에서 Co-S-W 상이 형성된 M 도핑 WS_x (M = Co, Ni)에서도 유사하게 발생한다.In general, crystalline molybdenum disulfide (c-MoS ₂ ) is used as an electrocatalyst and photocatalyst in a hydrogen evolution reaction (HER). In addition, the catalytic electrocatalyst HER, which is based on MoS ₂ , also exhibits excellent performance. For example, MoS ₂ electrodeposited on polypyrrole is used as an anode for hydrogen production, and it exhibits a low Tafel slope of 29 mV decade ⁻¹ , which shows similar performance to the used Pt catalyst. For hydrodesulfurization and oxygen evolution reaction (OER), doping of transition metals (e.g. Co, Ni, Cu and Fe) was performed on transition metal dichalcogenides (TMD). , Co-SW, Co-S-Mo, and Ni-SW, etc. have been modified in chemical structure and form by forming bimetallic active centers through sulfur bonds. Doping of Co ions into the MoS ₂ lattice reduces R _ct and promotes the formation of more active sites, thereby improving water separation performance. Hydrogen absorption free energy of M-doped MoS ₂ (M = Co, Ni, Fe, Cu) in HER (

G _H ) is better for Co-doped MoS ₂ and Fe-doped MoS ₂ than bare MoS ₂ in hydrogen production. In addition, Co, Ni, and Fe ions promote MoS ₃ film growth, thereby increasing the surface area and thereby improving hydrogen generation performance. MoS _x Co _y electrodeposited on TiO ₂ nanotube arrays form Mo-S-Co bonds to enhance the formation of active centers (unsaturated Mo and S sites) and enhance the electrocatalytic activity in MoS _x in HER. This is because the CoMoS phase is formed, so that at the S-edge of MoS ₂ R _ct and

Because G _H is reduced, The enhancement of HER yield similarly occurs for M-doped WS _x (M = Co, Ni) where Co-SW phase is formed within the structure.

Metal-organic frameworks (MOFs) are a new member of a family of porous material products composed of organic linkers such as metal clusters/ions. They consist of metal clusters/ions and organic linkers and are referred to as secondary building units (SBUs). The structure of MOFs can be modified by adjusting the chemical composition, and the choice of SBU depends on the specific application. MOFs are used in a wide range of applications such as gas absorption, catalysis, sensors, and drug delivery. MOF has a high surface area and high porosity, so it is widely applied in catalysts.

On the other hand, these MoS ₂ and There is a problem that MOF alone has lower performance than commercially available Pt in the reaction of generating hydrogen using water splitting.

In an embodiment of the present invention, MoS ₂ and By using MOF but modifying them, MoS ₂ and It is possible to provide a composite for a hydrogen generation catalyst that has better performance than MOF and can replace commercially available Pt.

Specifically, the MOF is transformed into a first transition metal to prepare a body portion, and then a sulfur compound containing a second transition metal of a controlled size and shape is provided on the outer surface of the body portion including the first transition metal, The yield of hydrogen generation in the composite for hydrogen generation catalyst can be further improved.

The first transition metal may be cobalt or nickel, and the second transition metal may include a transition metal different from the second transition metal. More specifically, the second transition metal may be molybdenum. In addition, the MOF may include a MOF-74 system.

When the first transition metal is cobalt (Co), the shape of the body is provided in a rod shape, and the primary particles are nanoparticles that are vertically anchored on the outer surface of the body. and can be provided. In addition, when the first transition metal is nickel (Ni), the shape of the body is provided with secondary particles formed by aggregation of a plurality of rod-shaped primary particles, and the primary particles are nanoparticles ( A nanoparticle may be vertically anchored on the outer surface of the body part.

Based on 100 parts by weight of the body part, the primary particles may be provided in 20 parts by weight to 60 parts by weight. Therefore, the catalytic activity is lowered, and if it exceeds 60 parts by weight, the primary particles cover the entire body part, and the water decomposition yield may be lowered.

Specifically, the first transition metal is Co or Ni, the second transition metal is Mo, and the composite for hydrogen generation catalyst may include 5wt% to 40wt% of a CoMoS phase or a NiMoS phase. In the composite for the hydrogen generation catalyst, if the content of the CoMoS phase or NiMoS phase is less than 5wt%, the catalytic activity is low, and if it exceeds 40wt%, the durability may be relatively deteriorated.

In addition, the body portion may have a specific surface area of 300 m2/g to 500 m2/g. If it is less than 300 m2/g, the amount of primary particles attached is low, and if it exceeds 500 m2/g, the primary particles may be uniformly attached. difficult and problematic

The onset potential by linear sweep voltammetry (LSV) may be -280mV to -140mV when the first transition metal is Co, and 100mV to 350mV when the first transition metal is Ni. Since the onset potential for linear sweep voltammetry can be controlled according to the type of the first transition metal, the use of the composite for a catalyst for generating hydrogen according to this embodiment can be applied in a more diverse manner.

According to another aspect of the present invention, the present invention comprises the steps of preparing a body part by reacting for a first temperature and a first time using a first solution containing a first transition metal; and a plurality of primary particles including the second transition metal on the outer surface of the body by mixing the body with a second solution containing the second transition metal, adding a third solution, and reacting at a second temperature and for a second time. A method for producing a composite for a hydrogen generation catalyst comprising a step of coating; including, wherein the metal organic framework is MOF-74-based and the first transition metal is nickel (Ni) or cobalt (Co). do.

내지 120

이고, 상기 제1 시간은 20시간 내지 30시간이고, 상기 제2 용액은 (NH₄)₂MoS₄이고, 상기 제3 용액은 히드라진 하이드레이트이고, 상기 제2 온도는 200

내지 300

이고, 상기 제2 시간은 8시간 내지 15시간일 수 있다.The method for preparing the composite for the hydrogen generation catalyst may use a solvothermal synthesis method, wherein the first solution is Co(NO ₃ ) ₂ .6H ₂ O or Ni(NO ₃ ) ₂ .6H ₂ O, and the first temperature is 80

to 120

, the first time is 20 to 30 hours, the second solution is (NH ₄ ) ₂ MoS ₄ , the third solution is hydrazine hydrate, and the second temperature is 200

to 300

And, the second time may be 8 hours to 15 hours.

When the first temperature and the first time and the second temperature and the second time are carried out within the above range, the reaction is completed and a hydrogen generating catalyst composite having a desired crystallinity can be prepared.

Examples and comparative examples of the present invention are described below. However, the following examples are only preferred embodiments of the present invention, and the scope of the present invention is not limited by the following examples.

1. Preparation of composite for hydrogen generation catalyst

ingredient

Hereinafter, the materials used in this experiment were purchased and used from the following companies.

Co(NO ₃ ) ₂ .6H ₂ O, H ₄ DHBDC, 5% Nafion solution, hydrazine hydrate, and (NH ₄ ) ₂ MoS ₄ were purchased from Sigma-Aldrich, and DMF was It was purchased from Daihan Chemical Co. Ltd. and used. Ethanol and methanol were purchased from Daejung Co. Ltd., and deionized water was prepared using a Millipore Mili-Q machine.

Preparation Example 1 (Preparation of Co-MOF-74)

0.1 mmol Co(NO ₃ ) ₂ .6H ₂ O (Cobalt nitrate hexahydrate) in a mixed solvent of 3 mL N, N-dimethylformamide, 3 mL ethanol and 3 mL DI water , 0.05 mmol H ₄ DHBDC acid (2,5-dihydroxybenzenedicarboxylic acid) was added to prepare a reaction mixture. The prepared reaction mixture was stirred for 30 minutes, transferred to a glass vial (10 mL), and reacted in an oven at 100 °C for 24 hours. After the reaction was completed, the glass vial was cooled to room temperature and centrifuged to obtain dark purple crystals. The obtained crystals were washed several times with methanol, dried under vacuum at 250 °C to obtain Co-MOF-74, and stored in a glass vial.

Preparation Examples 2 to 5 (Preparation of MoS _x /Co-MOF-74 composite)

After mixing 100 mg of Co-MOF-74 prepared in Preparation Example 1 with (NH ₄ ) ₂ MoS ₄ (Ammonium tetrathiomolybdate) having different content ranges as shown in Table 1 below, DMF (100 mL) was added to the mixture. was manufactured. While magnetically stirring the prepared mixture, 1 mL hydrazine hydrate was added dropwise from the top for 1 hour to prepare a compound. Then, the prepared compound was placed in a stainless steel autoclave treated with Teflon and maintained at 200° C. for 10 hours. Finally, the product was isolated, washed with deionized water and dried in a vacuum oven at 60 °C. Figure 2a is a view schematically showing a method for preparing the MoS _x /Co-MOF-74 composite.

division Preparation Example 2 Preparation Example 3 Production Example 4 Preparation Example 5 20% MoS _x /Co-MOF-74 40% MoS _x /Co-MOF-74 60% MoS _x /Co-MOF-74 80% MoS _x /Co-MOF-74 MoS _x content 20wt% 40wt% 60wt% 80wt%

Production Example 6 (Production of Ni-MOF-74)

Ni-MOF-74 was synthesized by solvothermal synthesis. 1 g Ni(NO ₃ ) ₂ .6H ₂ O and 0.2 g H ₄ DHBDC acid were added to 100 mL of a solvent mixed with DMF, deionized water and C ₂ H ₅ OH (vol%, 1:1:1) and stirred to obtain a reaction mixture. was made with The prepared reaction mixture was stirred for 1 hour and placed in a reactor composed of a stainless steel autoclave treated with Teflon. The reactor was transferred to an oven and maintained at 100 °C for 24 hours. Then, after cooling to 25 °C, a product containing a tan powder was separated using a centrifugal separator. The separated product was rinsed 4 times with methanol to remove the residue and dried in a vacuum oven at 170 °C for 5 hours to prepare Ni-MOF-74, which was stored in a glass vial.

Preparation Examples 7 to 10 (Preparation of MoS _x /Ni-MOF-74 composite)

100 mg of Ni-MOF-74 prepared in Preparation Example 6 was mixed with (NH ₄ ) ₂ MoS ₄ having different content ranges as shown in Table 2 below, and then DMF (100 mL) was added to prepare a mixture. While magnetically stirring the prepared mixture, 1mL hydrazine hydrate was added dropwise from the top for 1 hour to prepare a compound. Then, the prepared compound was placed in a stainless steel autoclave treated with Teflon and maintained at 200° C. for 10 hours. Finally, the product was isolated, washed with deionized water and dried in a vacuum oven at 60 °C. Figure 2b is a view schematically showing a method for preparing the MoS _x /Co-MOF-74 composite.

division Preparation Example 7 Preparation Example 8 Preparation Example 9 Preparation Example 10 20% MoS _x /Ni-MOF-74 40% MoS _x /Ni-MOF-74 60% MoS _x /Ni-MOF-74 80% MoS _x /Ni-MOF-74 MoS _x content 20wt% 40wt% 60wt% 80wt%

2. Evaluation of composites for hydrogen generation catalysts

Electrochemical performance evaluation

The HER electrocatalytic activity of the prepared hydrogen production catalyst composite was evaluated at room temperature using an electrochemical analyzer (Ivium potentiostat V55630) in a three-electrode system. Here, the sample is coated on a working electrode, glassy carbon electrode (GCE) (0.2 mg cm ^-2 ), a graphite rod as a counter electrode, and Hg/Hg ₂ Cl ₂ (saturated KCl) or reversible hydrogen (RHE) as a reference electrode. electrode) was used, and 0.5 MH ₂ SO ₄ was used as an electrolyte.

As a working electrode related to Preparation 1 to Preparation Example 5, in order to prevent the catalyst from adhering to the electrode, a mixture was prepared using 1 mg catalyst, 1 μL DMF, and 80 μL Nafion (Nafion, 5%) used A 0.5 μL mixture was prepared by sonication for 1 hour and then coated with GCE to a 3 mm diameter.

The obtained potential (vs. Hg/Hg ₂ Cl ₂ ) was converted to RHE (Real Hydrogen Electrode) using Equation 1 below.

(Equation 1) E(RHE) = E(Hg/Hg ₂ Cl ₂ ) + 0.059 pH + E ⁰ (Hg/Hg ₂ Cl ₂ )

As working electrodes related to Preparation Examples 6 to 10, a mixture was prepared using 4 mg catalyst, 1 µL DMF, and 80 µL Nafion (5%).

The obtained potential (vs. RHE) was converted to RHE (Real Hydrogen Electrode) using Equation 2 below.

(Equation 2) E (RHE) = E ⁰ (SCE) + E (SCE) + 0.059pH

LSV (linear sweep voltammetry) method was performed at a scan rate of 10 mV / s, EIS (Electrochemical impedance spectroscopy) was 0.2 V (vs. RHE), and the frequency range was 100000 Hz to 0.1 Hz. Catalyst stability was confirmed by cyclic voltammetry at a scan rate of 50 mV/s and chronoamperometry at -0.197 V.

Material characterization

The phase of each material was measured by XRD (D8-Advance/Bruker-AXS, Cu Kα radiation). The surface area of the material was confirmed by the Brunauer-Emmett-Teller (BET) method, and an FT-IR spectrum was obtained using a Perkin Elmer Spectrum GX1 spectrometer. SEM images were obtained with SIGMA/Carl Zeiss, HR-TEM images were obtained with JEOL-2100F (Japan), and XPS was confirmed in a high vacuum state using a Mg Kα source and pass energy of 40 eV or 50 eV.

3. Evaluation results

(1) Evaluation of Preparation Examples 1 to 5

Figure 3a is the powder XRD spectrum of 40% MoS _x /Co-MOF-74, Figure 3b is the FT-IR spectrum of Co-MOF-74, Figure 3c is Co-MOF-74 and 40% MoS _x /Co- It is a graph showing nitrogen adsorption and desorption of MOF-74.

Figure 3a shows the crystallinity of 40% MoS _x /Co-MOF-74 confirmed by XRD. Two types of peaks of Co-MOF-74 were measured at 2θ = 6.8 ^o and 2θ = 11.7 ^o and identified as the (2 -1 0) and (3 0 0) planes, respectively. This means that Co-MOF-74 was successfully synthesized. Figure 3b is the result of confirming the formation of active Co-MOF-74 according to Preparation Example 1 by FT-IR spectrum. The very low vibrational signal intensity at 1662 cm ⁻¹ is believed to be due to the DMF solvent. Numerous guest molecules were removed from Co open sites by thermal activation. In addition, the bands at 1554 cm ^-1 and 1409 cm ^-1 are respectively organic linkers. It is judged by the stretching vibrations of C=O (-COOH) and C=C (aromatic ring) bonds. 3c shows porosity characteristics evaluated by a _nitrogen adsorption isotherm according to Preparation Example 1 (Co-MOF-74). Specifically, Co-MOF-74 had a specific surface area of 335.4 m ² /g, a pore volume of 0.021 cm ³ /g, and an average pore size of 3.06 nm. After mixing Co-MOF-74 with 40wt% MoS _x , the surface area of 40% MoS _x /Co-MOF-74 decreased to 126.6 m ² /g. The pore volume remained unchanged (0.022 cm ³ /g), and the average pore size increased to 7.39 nm.

4 shows (a) Co-MOF-74, (b) 20% MoS _x /Co-MOF-74, (c) 40% MoS _x /Co-MOF-74, (d) 60% MoS _x /Co- SEM images of MOF-74, (e) 80% MoS _x /Co-MOF-74, and (f) MoS _x .

Figure 4 (a) to (f) shows the morphology of MoS _x /Co-MOF-74 prepared using Co-MOF-74 and (NH ₄ ) ₂ MoS ₄ of different contents of 0 to 100 wt%, respectively. It is the SEM image shown. Referring to FIG. 4, it was observed that MoS _x gradually increased on the outer surface of Co-MOF-74 from (a) to (e). On the other hand, when using a low content of 20% (NH ₄ ) ₂ MoS ₄ , it was confirmed that a small portion of the Co-MOF-74 crystal was not coated. At high content, Co-MOF-74 was covered on the outer surface, thereby confirming that the MoS _x /Co-MOF-74 composite was successfully synthesized. Referring to FIG. 4(c), 40% MoS _x is sufficient to completely cover Co-MOF-74, but overloading the outer surface of Co-MOF-74 with MoS x (> 40%) hinders the formation of the CoMoS phase, This can lead to a decrease in the activity of the complex catalyst.

5 is TEM images of (a) and (d) Co-MOF-74, (b) and (e) MoS _x , (c) and (f) 40% MoS _x /Co-MOF-74, respectively. Referring to FIGS. 5(a) and 4(b), Co-MOF-74 appeared in the form of a rod shape, and MoS _x was observed in the form of nanoparticles. In Fig. 5(c), the TEM image of 40% MoS _x /Co-MOF-74 showed that MoS _x was vertically immobilized on the outer surface of Co-MOF-74.

Figure 6 is the XPS spectrum of Co-MOF-74 and 40% MoS _x /Co-MOF-74, (a) is Co 2 p, (b) is Mo 3 d and S 2 s, (c) is S 2 p is shown respectively.

Referring to FIG. 6(a), in the XPS spectrum of Co 2p , the two peaks corresponding to Co ²⁺ 2p _1/2 and Co ²⁺ 2p _3/2 have binding energies of 797.6 eV and 781.8 eV, respectively. and the XPS spectrum of Co 2p for the MoS _x /Co-MOF-74 composite. In addition, two new peaks at 779.2 eV and 793.9 eV for saturated Co imply the presence of a CoMoS phase.

In Co-MOF-74, which normally has an open metal site (OMS) (Co site), it can readily interact with heteroatoms. Therefore, Co sites are predicted to interact with the S (or Mo) atoms of MoSx to form the CoMoS phase. The content of the CoMoS phase in the 40% MoS _x /Co-MOF-74 composite is estimated to be 18.9%, which is shown in the high resolution Mo 3 d and S 2 s in FIG. 6(b). The two peaks at 228.8 eV and 231.9 eV are due to Mo ⁴⁺ , and the peaks at 235.8 eV and 232.7 eV are due to Mo ⁵⁺ . The S 2p peaks at 164.1 eV and 162.9 eV are due to disulfide S ₂ ^2- , and the divalent sulfide ion (S ^2- ) is due to peaks at 162.7 eV and 161.5 eV (FIG. 6(c)).

Figure 7 shows (a) polarization curve, (b) Tafel slope, (c) EIS Nyquist plot of Co-MOF-74 and 20-100% MoS _x /Co-MOF-74 , (d) C _d and 40% MoS _x /Co-MOF-74 (e) cycle test after 1000 cycles, (f) a graph showing a chronoamperometric curve at a fixed voltage of 0.197 V.

7 shows the electrocatalytic properties of HER (hydrogen evolution reaction) for Co-MOF-74, MoS _x /Co-MOF-74 and compatible Pt/C. Referring to FIG. 7(a), in linear sweep voltammetry (LSV), the catalytic activity of Pt/C showed the best results at an onset potential of ~ 0 mV. In addition, the onset potentials of MoS _x /Co-MOF-74 with 20, 40, 60, and 80% (NH ₄ ) ₂ MoS ₄ were -287, -147, -188, -189 mV, respectively, and Co- The onset potentials of MOF-74 and MoS _x are respectively -589 and -177 mV. Here, it was confirmed that 40% MoS _x /Co-MOF-74 showed the best value. The Tafel slope shown in FIG. 7(b) is the result obtained by FIG. 7(a).

As a catalyst, Co-MOF-74 showed a relatively high Tafel slope of 249.2 mV decade ^-1 in hydrogen production. In addition, in Co-MOF-74 modified by MoS _x , the Tafel slope tended to decrease as the content of MoS _x increased. 40% MoS _x /Co-MOF-74 showed the lowest Tafel slope with 68.3mV decade ^-1 , and 20% MoS _x /Co-MOF-74 showed the highest Tafel slope with 132.6mV decade ^-1 . In the Tafel slope, 60% MoS _x /Co-MOF-74, 80% MoS _x /Co-MOF-74 and MoS _x showed low values of 68.8, 70.5 and 70.2 mV decade ^-1 , respectively. That is, it is determined that 40% MoS _x /Co-MOF-74 is due to the formation of a CoMoS phase that reduces the hydrogen absorption free energy, and represents the optimal content for improving the catalytic activity of Co-MOF-74. In addition, MoS _x plays an important function in HER performance. First, Mo ⁴⁺ and Mo ⁵⁺ act as a cocatalyst in a complex having an unsaturated atmosphere, and S ₂ ^2- acts as a center of HER catalytic activity. Second, MoS _x can enhance the HER performance of the MoS _x /Co-MOF-74 composite by creating a CoMoS phase. Tafel slope values are related to HER mechanisms including Volmer (120 mV decade ^-1 ), Heyrovsky (40 mV decade ^-1 ), and Tafel (30 mV decade ^-1 ). have. In general, there are two mechanisms in which water is separated in an acid medium to produce hydrogen, which consists of a Volmer-Heyrovsky reaction and a Volmer-Tafel reaction, and is represented by the following formulas (1) to (3).

Volmer reaction: H ₃ O ⁺ + e ^- → H* + H ₂ O (1)

Heyrovsky reaction: H ₃ O ⁺ + e ^- + H* → H ₂ + H ₂ O (2)

Tafel reaction: H* + H* → H ₂ (3)

The Co-MOF-74 composite modified by MoS _x has a Tafel slope in the range of 68 to 133 mV decade ^-1 , and the HER mechanism corresponding to the Volmer-Heyrovsky reaction includes a discharge process and electrochemical desorption.

Referring to FIG. 7(c), the HER yield was confirmed by measuring the EIS at 0.2V in an acidic solution (0.5 MH ₂ SO ₄ ). The equivalent circuit includes R _{s (} internal resistance), R _ct (Charge-transfer resistance), and CPE (Constant phase element) (internal diagram of FIG. 7(c)). The R _ct of the specimens including the catalytic resistance of GCE (R ₁ ) and the catalytic resistance of the electrolyte are shown in Table 3 below.

Sample R _S (Ω) R ₁ (Ω) R ₂ (Ω) Co-MOF-74 21.7 11390 3375 20% MoS _x /Co-MOF-74 13.5 285.8 101.7 40% MoS _x /Co-MOF-74 12.08 44.8 9.75 60% MoS _x /Co-MOF-74 17.8 58.6 21.5 80% MoS _x /Co-MOF-74 11.9 73.1 28.1 MoS _x 21.4 34.1 15.6

As described above, Co-MOF-74 has a high Tafel slope and low electrocatalytic activity with a high R ₁ of 11390 Ω. It was confirmed that as the ratio of MoS _x increased, the Rct of the MoS _x /Co-MOF-74 composite significantly decreased. Among them, 40% MoS _x /Co-MOF-74 with R1 and R2 of 44.8 Ω and 9.75 Ω, respectively, was confirmed to be the best. In addition, _in order to confirm the double layer capacitance (C _dl ) related to the electrochemically active surface area, as a result of CV measurement at various scan rates in the potential range of 0.1 ~ 0.2V (vs. RHE), the C _dl value is It was confirmed that the increase and decrease in the complex. In particular, 40% MoS _x /Co-MOF-74 showed the highest C _dl of 0.84 mF/cm 2 , and MoS _x showed a low C _dl of 0.43 mF/cm 2 . That is, it was confirmed that MoS _x /Co-MOF-74 has excellent catalytic activity compared to other composites.

The durability of 40% MoS _x /Co-MOF-74 as a catalyst was confirmed by current density-voltage chronometry. Referring to FIG. 7(e), it was confirmed that there was almost no change in the polarization curve after 1000 cycles, and it was confirmed that the current density did not change even after 12 hours (FIG. 7(f)). That is, 40% MoS _x /Co-MOF-74 shows high catalytic activity and stability, and shows excellent ability as a HER catalyst.

As described above, the catalytic activity consisting of Co-MOF-74 alone and the modified Co-MOF-74 using (NH ₄ ) ₂ MoS ₄ as a precursor The HER performance was confirmed by confirming the catalytic activity of Co-MOF-74. Co-MOF-74 in rod shape was prepared by solvothermal method and had a surface area of 335.4 m ² /g. The catalyst of 40% MoS _x /Co-MOF-74 has a Tafel slope of 68 mV decade ^-1 and an onset potential It was confirmed that it worked most effectively in hydrogen generation at -147 mV. In addition, 40% MoS _x /Co-MOF-74 showed high durability even after 1000 cycles, which is believed to be because the CoMoS phase promotes catalytically active centers and reduces the electron transfer resistance of Co-MOF-74. .

(2) Evaluation of Preparation Examples 6 to 10

Figure 8a is the powder XRD spectrum of 40% MoS _x /Ni-MOF-74, and Figure 8b is the FT-IR spectrum of Ni-MOF-74. 8C is a graph showing nitrogen adsorption and desorption of Ni-MOF-74 and 40% MoS _x /Ni-MOF-74.

= 6.8^o 및 11.7^o의 두개의 피크가 나타났고, 이는 Ni-MOF-74가 잘 합성되었음을 의미한다. 40% MoS_x/Ni-MOF-74는 MoS_x가 장착되어 결정도가 상대적으로 감소하였으나, 전체적으로 Ni-MOF-74의 결정 격자는 변하지 않음을 확인할 수 있었다. 이는 MoS_x가 비결정성 구조(amorphous structure)이기 때문으로 판단된다. 도 8b를 참조하면, 열방법에 의하여 활성화된 Ni-MOF-74는 1662 cm^-1 에서 낮은 진동 시그널 강도를 갖고, 이는 Ni 자리 활성화 과정에서 용매 분자가 현저하게 제거되었기 때문이다. 또한, C-O (H) 결합이 1193 cm^-1의 진동 주파수로 나타나는 과정에서, C=O (-COOH)의 비대칭 및 대칭 신축진동(stretching vibrations) 주파수는 각각 1557 cm^-1 및 1417 cm^-1이였다. 도 8c에서는 질소 흡착등온선(N₂ sorption isotherm)으로 평가한 기공 특성을 평가하였다. Ni-MOF-74는 435㎡/g의 상대적으로 높은 표면적으로 나타내고, 이에 의하여 상기 Ni-MOF-74의 표면에 MoS_x가 용이하게 고정되도록 할 수 있다. 또한, 40% MoS_x/Ni-MOF-74의 표면적은 Ni-MOF-74보다 더 크게 나타났는데, 이는 표면에 고정된 MoSx의 분포에 기인하는 것으로 판단된다. Referring to FIG. 8a, the crystal phases of Ni-MOF-74 and 40% MoS _x /Ni-MOF-74 were confirmed by XRD spectrum, and the crystal planes of Ni-MOF-74 (2 -1 0) and (3 0 0) approximately 2 representing each

= 6.8 ^o and 11.7 ^o appeared, indicating that Ni-MOF-74 was synthesized well. Although the crystallinity of 40% MoS _x /Ni-MOF-74 was relatively reduced due to the presence of MoS _x , it was confirmed that the crystal lattice of Ni-MOF-74 did not change overall. This is considered to be because MoS _x has an amorphous structure. Referring to FIG. 8B, Ni-MOF-74 activated by a thermal method has a low vibration signal intensity at 1662 cm ⁻¹ , because solvent molecules are significantly removed during the Ni site activation process. In addition, in the course of the CO (H) bond appearing at a vibration frequency of 1193 cm ^-1 , the asymmetric and symmetric stretching vibrations of C=O (-COOH) were 1557 cm ^-1 and 1417 cm ^-1 respectively. . In FIG. 8c, the pore characteristics evaluated by the nitrogen adsorption isotherm (N ₂ sorption isotherm) were evaluated. Ni-MOF-74 exhibits a relatively high surface area of 435 m 2 /g, whereby MoS _x can be easily immobilized on the surface of the Ni-MOF-74. In addition, the surface area of 40% MoS _x /Ni-MOF-74 was larger than that of Ni-MOF-74, which is believed to be due to the distribution of MoSx fixed on the surface.

9 shows (a) Ni-MOF-74, (b) 20% MoS _x /Ni-MOF-74, (c) 40% MoS _x /Ni-MOF-74, (d) 60% MoS _x /Ni- SEM images of MOF-74, (e) 80% MoS _x /Ni-MOF-74, and (f) MoS _x .

Referring to FIG. 9, it was confirmed that Ni-MOF-74 formed secondary particles having a flower-like structure by aggregating primary particles of rod-shaped crystals. Referring to the form in which MoSx is gradually fixed on the surface of Ni-MOF-74, in 20% MoS _x /Ni-MOF-74, a part of the Ni-MOF-74 surface is empty, and MoS _x is Ni-MOF- It was confirmed that it was provided in 74. On the other hand, when the content of MoS _x was increased, it was confirmed that the Ni-MOF-74 crystal was fixed vertically to the surface. On the other hand, if the content of MoS _x is excessively increased, the formation of the NiMoS phase may be hindered, thereby reducing the yield of the electrocatalyst HER. In an embodiment of the present invention, 40% MoS _x /Ni-MOF-74 may be preferred.

10 is TEM images of (a) and (d) Ni-MOF-74, (b) and (e) MoS _x , (c) and (f) 40% MoS _x /Ni-MOF-74, respectively.

Referring to FIG. 10, it was confirmed that the size of the Ni-MOF-74 crystal was approximately 300 nm and the diameter of MoS _x was 150 nm. In FIG. 10(c), it was confirmed that MoS _x was fixed on the Ni-MOF-74 surface. The HR-TEM image showed a lattice fringe of 0.197 nm representing the (5–10) plane of Ni-MOF-74, indicating that the crystals of Ni-MOF-74 were maintained even after MoS _x was immobilized on the surface ( 10(d), (f)). Here, MoS _x does not appear in the HR-TEM image because it has an amorphous structure (FIG. 10(e)).

Figure 11 is the XPS spectrum of Ni-MOF-74 and 40% MoS _x /Ni-MOF-74, (a) Ni 2p , (b) Mo 3 d and S 2 s, (c) is S 2 p is shown respectively.

In FIG. 11, XPS spectra were confirmed to confirm the chemical states of Ni-MOF-74 and 40% MoS _x /Ni-MOF-74. 11(a) shows the XPS spectrum of Ni 2p, and two peaks appeared at 874.0.6 eV and 856.3 eV, which represent Ni ²⁺ 2p _1/2 and Ni ²⁺ 2p _3/2 , respectively. On the other hand, saturated Ni appears at 880.2 eV and 861.9 eV. This peak was also observed in 40% MoS _x /Ni-MOF-74, which means that a stable Ni-MOF-74 structure was formed. Also, two new small peaks at 871.6 eV and 853.7 eV are attributed to the presence of the NiMoS phase. The NiMoS phase is formed by the interaction between Ni open sites and S (or Mo) atoms in MoS _x . In FIG. 11(b), a peak was confirmed at 235.9 eV, 232.8 eV means the oxidation state of Mo ⁵⁺ , and the oxidation states of Mo ⁴⁺ 3d _3/2 and Mo ⁴⁺ 3d _5/2 are 231.9 eV, respectively. and 228.8 eV. The peaks of disulfide ions (S ₂ ^2- ) appeared at 163.9 eV and 162.7 eV, and the peaks of divalent sulfide ions (S ^2- ) appeared at 162.5 eV and 161.3 eV (FIG. 11(c)).

12 shows (a) polarization curves, (b) Tafel slopes, (c) electro-impedance spectroscopy (EIS) of Ni-MOF-74 and 20-100% MoS _x /Ni-MOF-74 Nyquist plot, (d) A graph showing a cycle test after 2000 cycles of 40% MoS _x /Ni-MOF-74.

In FIG. 12, Ni-MOF-74, 20% MoS _x /Ni-MOF-74, 40% MoS _x /Ni-MOF-74, 60% MoS _x /Ni-MOF-74, 80% MoS _x /Ni-MOF -74, and HER electrocatalytic activity of MoS _x . In addition, for comparison, the hydrogen generation performance was evaluated using a compatible Pt/C catalyst. 12(a) shows a linear sweep voltammetry (LSV) plot. Currently, Pt is regarded as the best catalyst for hydrogen generation, with the Pt/C electrode showing the lowest onset potential of ~0 mV and Ni-MOF-74 showing the highest onset potential of 320 mV. On the other hand, it was confirmed that the catalytic activity of MoS _x /Co-MOF-74 with MoS _x immobilized on Ni-MOF-74 was greatly improved. In particular, 20% MoS _x /Ni- _MOF -74, 40% MoS x /Ni-MOF-74, 60% MoS _x /Ni-MOF catalysts with 20%, 40%, 60%, 80% MoS _x The -74 and 80% MoS _x /Ni-MOF-74 composites showed onset potentials of 302, 117, 120, and 191 mV, respectively, whereas MoSx showed an onset potential of 153 mV. In particular, it was confirmed that 40% MoS _x /Ni-MOF-74 required only a low overvoltage of 167 mV to generate a current density of 10 mA/cm 2 .

Fig. 12(b) shows the Tafel slope values of catalysts by linear plot of overpotential versus log(current density). The Ni-MOF-74 catalyst exhibited the highest Tafel slope of 115.4 mV dec-1 due to its high charge transfer resistance, whereas the 40% MoS _x /Ni-MOF-74 had the lowest Tafel slope of 53.1 mV dec-1, and hydrogen This means that the production rate is the fastest. 60% MoS _x /Ni-MOF-74 (60.3 mV dec-1) and 80% MoS _x /Ni-MOF-74 (60.7 mV dec-1) showed smaller Tafel slopes than MoS _x . This means that 40% MoS _x /Ni-MOF-74 shows the highest yield in HER through the electrochemical method, because 40% MoS _x /Ni-MOF-74 contains two types of active sites. It is judged as First, the NiMoS moiety reduced the hydrogen adsorption free energy, and second, MoS _x grown on the Ni-MOF-74 template provided active centers for unsaturated Mo and S. Formation of the NiMoS phase also increased the electrochemical surface area of the composite as determined from the double layer capacitance (C _dl ). In particular, it can be seen that 40% MoS _x /Ni-MOF-74 in C _dl is 2.77 mF/cm 2 , whereas Ni-MOF-74 and MoS _x show low values of 0.26 mF/cm 2 and 0.91 mF/cm 2 , respectively. there was.

Typically, the Tafel slope is related to HER kinetics and reaction mechanisms. Based on the obtained Tafel slope, it can be confirmed that when the MoS _x /Ni-MOF-74 composite is used as a catalyst, hydrogen is produced by combining the Volmer reaction and the Heyrovsky reaction, as shown in equations (1) and (2) below. can

H ₃ O ⁺ + e ^- → H* + H ₂ O (1)

H ₃ O ⁺ + e ^- + H* → H ₂ + H ₂ O (2)

EIS measurement was performed to evaluate the HER rate, and was performed at an overvoltage of 200 mV in H ₂ SO ₄ (0.5 M) solution. Referring to FIG. 12(c), an EIS Nyquist plot including an electric circuit including series resistance (Rs), charge transfer resistance (Rct), and a constant phase element (CPE) is shown. Referring to Table 3, Ni-MOF-74 showed a relatively large Rct of 8375 Ω, confirming that the hydrogen production yield was low. It was confirmed that the resistance decreased.

Sample R _S (Ω) _Rct (Ω) Ni-MOF-74 12.7 8375 20% MoS _x /Ni-MOF-74 14.6 289.2 40% MoS _x /Ni-MOF-74 16.5 40.4 60% MoS _x /Ni-MOF-74 16.6 59.6 80% MoS _x /Ni-MOF-74 16.7 79.3 MoS _x 16.4 125.0

40% MoS _x /Ni-MOF-74 showed a lower electrical conductivity than MoSx with an Rct of 40.4 Ω, which is considered to be due to the appearance of the NiMoS phase. In addition, as a result of checking the durability to confirm whether it is suitable for industrial application, the stability of 40% MoS _x /Ni-MOF-74 as an electrocatalyst was confirmed by the CV method as shown in FIG. 12 (d). After 2000 cycles, the overvoltage (current density of 10 mA/cm 2 ) increased from 167 to 170 mV, which means that the catalytic activity was reduced, which is considered to be due to the decrease in the amount of S ₂ ^2- .

As described above, the Ni-MOF-74 and MoS _x /Ni-MOF-74 composites were successfully prepared by solvothermal synthesis, and their performance was confirmed by hydrogen generation by water electrolysis. 40% MoS _x /Ni-MOF-74 (575 m2/g) showed a higher surface area than Ni-MOF-74 (435 m2/g), and 40% MoS _x /Ni-MOF-74 had a Tafel slope of 53 mV dec -1 and 40wt% of MoS ₂ in the composite with an onset potential of -114mV, it was found to be the most efficient hydrogen generation catalyst. In addition, MoS _x /Ni-MOF-74 showed high stability even after 2000 cycles, which is considered to be due to the formation of NiMoS phase and the large surface area due to the reduction of electrochemical surface area and hydrogen absorption.

Those skilled in the art to which the present invention pertains will understand that the present invention can be embodied in other specific forms without changing its technical spirit or essential features. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. The scope of the present invention is indicated by the claims to be described later rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts thereof are included in the scope of the present invention. should be interpreted

Claims (13)

a body portion including a first transition metal and a metal-organic framework (MOF); and
A plurality of primary particles provided on the outer surface of the body and including a second transition metal;
The metal organic framework is MOF-74-based, the first transition metal is nickel (Ni) or cobalt (Co),
The second transition metal is molybdenum (Mo) or tungsten (W),
The primary particles include MoSx,
The primary particles are provided to cover the outer surface of the body in the form of nanoparticles having a size smaller than that of the body, and the composite for hydrogen generation catalyst having a three-dimensional structure in which at least a part of the body is exposed to the outside. . delete delete delete delete According to claim 1,
Based on 100 parts by weight of the body part, the primary particles are provided in 20 parts by weight to 60 parts by weight. According to claim 1,
The body portion has crystal planes (2 -1 0) and (3 0 0) measured by XRD spectrum, and the primary particles have an amorphous structure. According to claim 1,
When the first transition metal is cobalt (Co), the body portion has a rod shape, and the primary particles are nanoparticles that are vertically anchored on the outer surface of the body portion. is provided,
When the first transition metal is nickel (Ni), the shape of the body is formed by aggregating a plurality of rod shapes, and the primary particles are nanoparticles that are vertically fixed on the outer surface of the body. A composite for a hydrogen generation catalyst provided by being anchored. According to claim 1,
Hydrogen including an onset potential by Linear Sweep Voltammetry (LSV) of -280mV to -140mV when the first transition metal is Co and 100mV to 350mV when the first transition metal is Ni Complex for production catalyst. According to claim 1,
The first transition metal is Co or Ni, the second transition metal is Mo, and the composite for a hydrogen generation catalyst comprising 5wt% to 40wt% of a CoMoS phase or a NiMoS phase. According to claim 1,
The body part has a specific surface area of 300 m 2 / g to 500 m 2 / g. preparing a body part by reacting a first solution containing a first transition metal at a first temperature and for a first time; and
The body part is mixed with a second solution containing a second transition metal, and a third solution is added to react for a second temperature and a second time period to form a plurality of primary particles containing the second transition metal on the outer surface of the body part. Including; coating;
Hydrogen according to any one of claims 1 and 7 to 11, wherein the metal organic framework is MOF-74, and the first transition metal is nickel (Ni) or cobalt (Co). A method for producing a composite for a production catalyst. According to claim 12,
The first solution is Co(NO ₃ ) ₂ .6H ₂ O or Ni(NO ₃ ) ₂ .6H ₂ O;
The first temperature is 80 ℃ to 120 ℃,
The first time is 20 hours to 30 hours,
The second solution is (NH ₄ ) ₂ MoS ₄ ,
The third solution is hydrazine hydrate,
The second temperature is 200 ℃ to 300 ℃,
The second time is a method for producing a composite for hydrogen generation catalyst of 8 hours to 15 hours.

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