CN103151535B - Preparation Technology of Nano-Fe3O4-V2O5-Au Doped Polythiophene Film Modified Mesh Glassy Carbon Electrode - Google Patents

Abstract

The invention discloses a preparation process of nanometer Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modified mesh glassy carbon electrode. Dissolve FeCl ₃ and NaAc in ethylene glycol and dry to obtain particle A; mix cetyltrimethylammonium bromide, n-octane, and n-butanol in two parts, add ammonium metavanadate and deionized water, stirred to obtain microemulsion A; the other part was added dilute sulfuric acid, stirred to obtain microemulsion B; mixed microemulsion A and B, centrifuged and washed, and roasted to obtain particle B; mixed particles A and B, added polyvinylpyrrolidone, HAuCl ₄ solution and deionized water, oscillated and centrifuged, washed and dried, and dissolved in absolute ethanol, 10 μL was dropped on the pretreated mesh glassy carbon electrode by oscillating, and the modified electrode A was obtained by standing still; 1 mL of thiophene was added to concentrated sulfuric acid, The modified electrode A was used as the working electrode to carry out electropolymerization reaction to obtain nano-Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modified network glassy carbon electrode.

Description

Preparation Technology of Nano-Fe3O4-V2O5-Au Doped Polythiophene Film Modified Mesh Glassy Carbon Electrode

technical field

The invention belongs to the technical field of chemically modified electrodes for electrocatalytic oxygen reduction, and in particular relates to a preparation process of nanometer Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film-modified mesh glassy carbon electrodes.

Background technique

In recent years, with the wide application of electrochemical technology in the environmental field, especially the electro-Fenton method to deal with pollution problems such as coking wastewater, how to improve the oxygen reduction catalytic performance of the cathode has become a research hotspot. Many studies have focused on modifying cathode materials to Improve its oxygen reduction catalytic performance.

At present, the materials for modifying cathodes in domestic and foreign research mainly include conductive polymers and inorganic magnetic composites. Conductive polymers usually have large π-bond conjugated structures, rigid chains, generally insoluble and infusible, and have good chemical and mechanical stability. Their monomers can be directly deposited on the surface of electrodes through electroactive polymerization, and then they are firm and difficult to generate active substances. Therefore, it has good reproducibility and long electrode life; and the conductive polymer is non-toxic and harmless, easy to prepare, and has high electrical conductivity and environmental stability. Aniline, polyphenylene, etc. Inorganic magnetic composites are cheap and rich in resources. As an important electrode material, they are widely used in supercapacitors, batteries, fuel cells, etc. The nanomaterials have unique electrocatalytic activity due to their small size effect and surface effect, and have been widely used As an oxygen reduction catalyst, Fe ₃ O ₄ , various ferrites, salts, and other transition metal oxides are more researched on nano-inorganic magnetic composites. Based on the above advantages, the complexation of conductive polymers and inorganic magnetic composites to modify the electrode can overcome their respective defects and achieve the purpose of improving the oxygen reduction catalytic performance of the cathode. However, in the current research, only one or two kinds of inorganic magnetic composites are complexed with a conductive polymer, and the conductive polymers are mostly polyaniline and its homologues, and the modified electrodes are mostly graphite and activated carbon, so many However, there is still a lack of research on the preparation process of a composite-modified mesh glassy carbon electrode.

Contents of the invention

The object of the present invention is to provide a preparation process of nanometer Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modified mesh glassy carbon electrode. The specific steps are as follows:

(1) Dissolve 5.30g _FeCl3 in 35mL ethylene glycol, add 5.28g NaAc under 1000r/min stirring condition and stir for 30min to obtain mixed solution A;

(2) Transfer the mixed solution A obtained in step (1) to a high-pressure digestion tank with a volume of 55 mL, heat to 200° C. and keep it warm for 10 hours to obtain a solid product B;

(3) The solid product B obtained in step (2) is centrifuged under the condition of 6000r/min at a rotating speed, then washed with 15mL of deionized water, washed twice, and washed once with 20mL of ethanol with a mass fraction of 95%. Dry at 60°C for 4 hours to obtain granule A;

(4) Add 3.00g of cetyltrimethylammonium bromide, 17.00mL of n-octane, and 5.00mL of n-butanol into a 250mL Erlenmeyer flask, then add 2.00g of ammonium metavanadate and 100mL of deionized water, Place in a 70°C water bath and stir for 15 minutes under the condition of 5000r/min to obtain microemulsion A;

(5) Add 3.00g of cetyltrimethylammonium bromide, 17.00mL of n-octane, and 5.00mL of n-butanol into a 250mL Erlenmeyer flask in sequence, then add 100mL of dilute sulfuric acid with a molar concentration of 0.80mol/L, Stirring 15min under the condition of 1000r/min, obtain microemulsion B;

(6) Mix the microemulsion A obtained in step (4) with the microemulsion B obtained in step (5), then stir at 1000r/min for 10min, let stand for 10h, then centrifuge at 6000r/min for 20min, remove The supernatant was washed with 15 mL of ethanol with a mass fraction of 95%, and the washing was repeated 5 times to obtain a solid product C;

(7) Drying the solid product C obtained in step (6) at 100°C for 24 hours, and then roasting in a muffle furnace at 500°C for 2 hours to obtain particles B;

(8) Add 20 mg of granule A obtained in step (3) and 20 mg of granule B obtained in step (7) into a 250 mL Erlenmeyer flask, then add 1.16 g of polyvinylpyrrolidone and 100 mL of deionized water, ultrasonically shake for 10 minutes, and add 1.00 mL of HAuCl ₄ solution with a mass concentration of 0.02g/mL, continue to sonicate for 5 minutes;

(9) Add 2.00 mL of 1% sodium citrate solution by weight to the Erlenmeyer flask of step (8), shake and react at 40° C. for 30 min, centrifuge at 6000 r/min for 15 min, remove the supernatant, Then wash with 15mL deionized water, repeat the washing twice, and dry at 20°C for 24h to obtain the solid product D;

(10) Use a puncher to make a 2-cm-diameter disc of glassy carbon with a thickness of 2 mm, soak it in 10 mL of hydrochloric acid with a molar concentration of 0.006 mol/mL for 12 hours, and then transfer it to a fume hood with 20 mL of Treat with water and methanol for 12 hours, then dry in an oven at 110°C for 24 hours to obtain a pretreated mesh glassy carbon electrode;

(11) Place 0.1 g of the solid product D obtained in step (9) in 10 mL of absolute ethanol, ultrasonically vibrate for 10 min, then take out 10 μL and drop it on the mesh glassy carbon electrode pretreated in step (10). Stand at ℃ for 30 minutes to obtain modified electrode A;

(12) Add 1 mL of thiophene to 10 mL of H ₃ PO ₄ solution with a molar concentration of 10 mol/L, as an electropolymerized ionic liquid, use the modified electrode A obtained in step (11) as a working electrode, and use a Pt electrode as a counter electrode, Using the Ag electrode as the reference electrode, 0-2V cyclic voltammetry polymerization for 10 cycles, the scanning speed is 45mV/s, to obtain nano Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modified network glassy carbon electrode .

The beneficial effect of the invention is that the prepared nanometer Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film-modified network glassy carbon electrode has high oxygen reduction catalytic performance and long electrode life.

Detailed ways

The present invention provides a preparation process of nanometer Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modified reticulated glassy carbon electrode, and an example is used to illustrate the implementation process.

Example 1.

Dissolve 5.30g _FeCl3 in 35mL ethylene glycol, add 5.28g NaAc and stir for 30min at 1000r/min to obtain mixed solution A and transfer it to a high-pressure digestion tank with a volume of 55mL, heat to 200°C and Insulate and react for 10 hours to obtain solid product B; then centrifuge solid product B at a rotational speed of 6000r/min, then wash with 15mL of deionized water, repeat the washing twice, and wash once with 20mL of ethanol with a mass fraction of 95% , placed at 60°C and dried for 4 hours to obtain Particle A.

Add 3.00g of cetyltrimethylammonium bromide, 17.00mL of n-octane, and 5.00mL of n-butanol into a 250mL Erlenmeyer flask, then add 2.00g of ammonium metavanadate and 100mL of deionized water, and place at 70 Stir in a water bath at 5000r/min for 15min to obtain microemulsion A; then add 3.00g of cetyltrimethylammonium bromide, 17.00mL of n-octane, and 5.00mL of n-butanol into a 250mL Erlenmeyer flask , then add 100 mL of dilute sulfuric acid with a molar concentration of 0.80 mol/L, stir at 1000 r/min for 15 min to obtain microemulsion B; mix microemulsion A with microemulsion B, then stir at 1000 r/min for 10 min, static Place for 10 h, then centrifuge at 6000 r/min for 20 min, remove the supernatant, wash with 15 mL of ethanol with a mass fraction of 95%, and repeat the washing 5 times to obtain solid product C, which is dried at 100 °C for 24 h, and then Place in a muffle furnace and bake at 500°C for 2 hours to obtain particle B.

Add 20mg of granule A and 20mg of granule B into a 250mL Erlenmeyer flask, then add 1.16g of polyvinylpyrrolidone and 100mL of deionized water, ultrasonically oscillate for 10min, add 1.00mL of HAuCl ₄ solution with a mass concentration of 0.02g/mL, and continue to sonicate 5min; then add 2.00mL of 1% sodium citrate solution by weight, shake and react at 40°C for 30min, centrifuge at 6000r/min for 15min, remove the supernatant, then wash with 15mL deionized water, repeat The solid product D was obtained after washing twice and drying at 20° C. for 24 h.

Use a puncher to make a 2cm-diameter disc from a mesh glassy carbon with a thickness of 2mm, soak it in 10mL of hydrochloric acid with a molar concentration of 0.006mol/mL for 12h, then transfer it to a fume hood and treat it with 20mL of anhydrous methanol 12h, then dried in an oven at 110°C for 24h to obtain a pretreated mesh glassy carbon electrode; put 0.1g of solid product D in 10mL of absolute ethanol, ultrasonically oscillate for 10min, then take out 10μL and drop it on the pretreated The modified mesh glassy carbon electrode was placed at 20°C for 30 minutes to obtain modified electrode A; then 1 mL of thiophene was added to 10 mL of H ₃ PO ₄ solution with a molar concentration of 10 mol/L to serve as an electropolymerized ionic liquid. The obtained modified electrode A was used as the working electrode, the Pt electrode was used as the counter electrode, and the Ag electrode was used as the reference electrode, 0-2V cyclic voltammetry was used for 10 cycles of polymerization, and the scanning speed was 45mV/s to obtain nanometer Fe ₃ O ₄ - V ₂ O ₅ -Au-doped polythiophene film modified mesh glassy carbon electrode.

The following is the treatment experiment of coking wastewater by using the nanometer Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modified mesh glass carbon electrode prepared by the method of the present invention to further illustrate the present invention.

Using the nano-Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modified network glassy carbon electrode prepared by the method of the present invention to treat coking wastewater, the results show that the electrode can efficiently treat volatile phenols in coking wastewater : When the concentration of volatile phenol in the wastewater is 284mg/L, the mesh glassy carbon electrode modified with nanometer Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film is the cathode, the pH is 3.5, and the voltage is 13V. The time is 30min, the concentration of volatile phenol after treatment is 16.43mg/L, and the treatment efficiency reaches 94.21%.

Claims (1)

1. A preparation process for a mesh glassy carbon electrode, characterized in that it adopts nanometer Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modification, the specific steps of the process are as follows: (1) Dissolve 5.30g _FeCl3 in 35mL ethylene glycol, add 5.28g sodium acetate under 1000r/min stirring condition and stir for 30min to obtain mixed solution A; (2) Transfer the mixed solution A obtained in step (1) to a high-pressure digestion tank with a volume of 55 mL, heat to 200° C. and keep it warm for 10 hours to obtain a solid product B; (3) The solid product B obtained in step (2) is centrifuged under the condition of 6000r/min at a rotating speed, then washed with 15mL of deionized water, washed twice, and washed once with 20mL of ethanol with a mass fraction of 95%. Dry at 60°C for 4 hours to obtain granule A; (4) Add 3.00g of cetyltrimethylammonium bromide, 17.00mL of n-octane, and 5.00mL of n-butanol into a 250mL Erlenmeyer flask, then add 2.00g of ammonium metavanadate and 100mL of deionized water, Place in a 70°C water bath and stir for 15 minutes under the condition of 5000r/min to obtain microemulsion A; (5) Add 3.00g of cetyltrimethylammonium bromide, 17.00mL of n-octane, and 5.00mL of n-butanol into a 250mL Erlenmeyer flask in sequence, then add 100mL of dilute sulfuric acid with a molar concentration of 0.80mol/L, Stirring 15min under the condition of 1000r/min, obtain microemulsion B; (6) Mix the microemulsion A obtained in step (4) with the microemulsion B obtained in step (5), then stir at 1000r/min for 10min, let stand for 10h, then centrifuge at 6000r/min for 20min, remove The supernatant was washed with 15 mL of ethanol with a mass fraction of 95%, and the washing was repeated 5 times to obtain a solid product C; (7) Drying the solid product C obtained in step (6) at 100°C for 24 hours, and then roasting in a muffle furnace at 500°C for 2 hours to obtain particles B; (8) Add 20 mg of granule A obtained in step (3) and 20 mg of granule B obtained in step (7) into a 250 mL Erlenmeyer flask, then add 1.16 g of polyvinylpyrrolidone and 100 mL of deionized water, ultrasonically shake for 10 minutes, and add 1.00 mL of HAuCl ₄ solution with a mass concentration of 0.02g/mL, continue to sonicate for 5 minutes; (9) Add 2.00 mL of 1% sodium citrate solution by weight to the Erlenmeyer flask of step (8), shake and react at 40° C. for 30 min, centrifuge at 6000 r/min for 15 min, remove the supernatant, Then wash with 15mL deionized water, repeat the washing twice, and dry at 20°C for 24h to obtain the solid product D; (10) Use a puncher to make a 2-cm-diameter disc of glassy carbon with a thickness of 2 mm, soak it in 10 mL of hydrochloric acid with a molar concentration of 0.006 mol/mL for 12 hours, and then transfer it to a fume hood with 20 mL of Treat with water and methanol for 12 hours, then dry in an oven at 110°C for 24 hours to obtain a pretreated mesh glassy carbon electrode; (11) Place 0.1 g of the solid product D obtained in step (9) in 10 mL of absolute ethanol, ultrasonically vibrate for 10 min, then take out 10 μL and drop it on the mesh glassy carbon electrode pretreated in step (10). Stand at ℃ for 30 minutes to obtain modified electrode A; (12) Add 1 mL of thiophene to 10 mL of H ₃ PO ₄ solution with a molar concentration of 10 mol/L, as an electropolymerized ionic liquid, use the modified electrode A obtained in step (11) as a working electrode, and use a Pt electrode as a counter electrode, Using the Ag electrode as the reference electrode, 0-2V cyclic voltammetry polymerization for 10 cycles, the scanning speed is 45mV/s, to obtain nano Fe ₃ O ₄ -V ₂ O ₅ -Au doped polythiophene film modified network glassy carbon electrode .