Yunling Zou
Liaoning Normal University, School of Chemistry and Chemical Engineer, Graduate Student
Porous CeO2 nanostructures were synthesized by a simple template method using cotton fibers as biomaterial template. The phase structure and morphology of the product were investigated by X-ray diffraction (XRD), transmission electron... more
Porous CeO2 nanostructures were synthesized by a simple template method using cotton fibers as biomaterial template. The phase structure and morphology of the product were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM). The UV-blocking property was evaluated by UV-Vis spectrophotometry. Experimental results showed that the as-synthesized CeO2 was in a cubic fluorite structure and presented fiber-like structure. The fiber-like CeO2 nanostructures completely recorded the original morphology of cotton fibers, which consisted of large amounts of coalescent CeO2 nanoparticles with average particle size in the range of 6-10 nm. The UV test result showed that the UV transmittance of the product was closer to zero in the wavelength below 350 nm, indicating that the product exhibited excellent UV-blocking property.
Research Interests:
Research Interests:
Abstract Metal oxide semiconductor-based sensors are widely used in medicine, industry, agriculture and environmental protection. In this paper, a series of different molar ratios of Sm were doped into SnO2 nanoparticles through a... more
Abstract Metal oxide semiconductor-based sensors are widely used in medicine, industry, agriculture and environmental protection. In this paper, a series of different molar ratios of Sm were doped into SnO2 nanoparticles through a coprecipitation route. The as-obtained Sm/SnO2 nanocomposites were analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and transmission electron microscope. The results indicated that Sm doping reduced the size of SnO2 nanoparticles and an Sm-O-Sn bond formed on the surface of Sm/SnO2 nanocomposites. The gas-sensing examination of the Sm/SnO2 nanocomposite-based sensor was assessed, and the results displayed that the fabricated sensor with a 4% molar ratio of Sm-decorated SnO2 exhibited a high response (138.9) and outstanding selectivity towards ethanol gas at 160 °C, and the limit of detection was as low as 100 ppb, implying a potential application in trace gas detection. Finally, the enhancement response of the Sm-doped SnO2 nanocomposites was discussed.
Research Interests:
Magnetite nanoparticles (Fe3O4-NPs)/orange peel (MOP) composite was prepared via one-step in-situ co-precipitation method as magnetic heterogeneous Fenton-like catalyst. The properties of MOP were characterized by scanning electron... more
Magnetite nanoparticles (Fe3O4-NPs)/orange peel (MOP) composite was prepared via one-step in-situ co-precipitation method as magnetic heterogeneous Fenton-like catalyst. The properties of MOP were characterized by scanning electron microscopy, transmission electron microscopes, Brunauer–Emmett–Teller, X-ray diffraction, Fourier-transform infrared, thermogravimetric analysis and X-ray photoelectron spectroscopy technologies. Its Fenton-like catalytic responses towards removal of methyl orange (MO) were investigated, in which the effects of initial dye concentration, pH, temperature and hydrogen peroxide dosage were studied. The MO degradation ratio up to 98.0% was obtained within 20 min in optimized conditions. The catalyst showed excellent catalytic stability exhibiting nearly 90% degradation ratio in the 10th cycle within 20 min, whereas pure Fe3O4-NPs showed only 62.5% in this stage. Due to the stabilization of complexing orange peel hydroxyl to iron oxide in the composite and its...
Research Interests:
Research Interests:
Cu-doped TiO2 having a brookite phase and showing enhanced visible light photocatalytic activity was synthesized using a mild solvothermal method. The as-prepared samples were characterized by various techniques, such as X-ray... more
Cu-doped TiO2 having a brookite phase and showing enhanced visible light photocatalytic activity was synthesized using a mild solvothermal method. The as-prepared samples were characterized by various techniques, such as X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-Vis diffuse reflectance spectroscopy. Photocatalytic activity of Cu-doped brookite TiO2 nanoparticles was evaluated by photodegradation of methylene blue under visible light irradiation. The X-ray diffraction analysis showed that the crystallite size of Cu-doped brookite TiO2 samples decreased with the increase of Cu concentration in the samples. The UV-Vis diffuse reflectance spectroscopy analysis of the Cu-doped TiO2 samples showed a shift to lower energy levels in the band gap compared with that of bare phase brookite TiO2. Cu doped brookite TiO2 can obviously improve its visible light photocatalytic acti...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Hollow ZnSnO3 nanospheres were synthesized by a hydrothermal method using ZnO nanospheres as the hard template and raw material simultaneously. The combined characterizations of X-ray diffraction (XRD), scanning electron microscope (SEM)... more
Hollow ZnSnO3 nanospheres were synthesized by a hydrothermal method using ZnO nanospheres as the hard template and raw material simultaneously. The combined characterizations of X-ray diffraction (XRD), scanning electron microscope (SEM) and high-resolution transmission electron microscopy (HRTEM) confirmed the successful preparation of hollow ZnSnO3 nanospheres. The gas-sensing results indicated that the sensor made from hollow ZnSnO3 nanospheres exhibited high sensitivity, good selectivity, and stability to ethanol at a low operating temperature of 200°C. The sensitivity was about 32 and the response and recovery time were about 4 s and 30 s for 100 ppm ethanol, respectively. The enhancement in gas-sensing properties was attributed to the hollow nanostructures and high specific surface areas of ZnSnO3.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
ABSTRACT In this work, uniform Zn2SnO4 nanoparticles were synthesized with a simple co-precipitation method followed by hydrothermal post-treatment process. For comparison, pure ZnO and SnO2 samples were obtained with the same method.... more
ABSTRACT In this work, uniform Zn2SnO4 nanoparticles were synthesized with a simple co-precipitation method followed by hydrothermal post-treatment process. For comparison, pure ZnO and SnO2 samples were obtained with the same method. These products were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and N2 absorption–desorption analysis. The ethanol-sensing properties of as-prepared Zn2SnO4 nanostructure sensor was systematically investigated and compared with the pure ZnO and SnO2 sensors. The results revealed that the Zn2SnO4-based sensor exhibited a low operating temperature, high response, good repeatability, and long-term stability toward ethanol gas.
Research Interests:
ABSTRACT A comparison between the initial reaction rates of nanometric and commercial NaH has been studied in four test reactions: 1) hydrogenolysis of chlorobenzene; 2) selective reduction of cinnamaldehyde to cinnamyl alcohol; 3)... more
ABSTRACT A comparison between the initial reaction rates of nanometric and commercial NaH has been studied in four test reactions: 1) hydrogenolysis of chlorobenzene; 2) selective reduction of cinnamaldehyde to cinnamyl alcohol; 3) metallation of dimethyl sulfoxide; and 4) catalytic hydrogenation of olefins. The experimental results indicate that when NaH is used as a chemical reagent in the first three reactions, the initial reaction rates of nano-NaH is 230, 120 and 110 times higher than those of the commercial ones respectively, and it is in agreement with the difference in specific surface areas between these two forms of NaH. When NaH is used as a catalyst component together with Cp2TiCl2 in the fourth reaction, catalyst with nano-NaH gives extremely high activity in the hydrogenation of olefins, while the one with commercial NaH gives no activity at all even if a large amount of the commercial NaH is used to make the total surface area equivalent to that of nano-NaH. Thus, it is evident that although large specific surface area is important for nano-NaH to be used as a catalyst component, high surface energy with surface defects seems to be more important. The large specific surface and the activated surface of nano-NaH with high surface energy should be the main factors for their extremely high chemical reactivity, while whether the former or the latter one plays a leading role depends on the type of reactions involved.
Research Interests:
A series of GnTiO2 {001} nanocomposites (GTN) with dominate exposed {001} facets has been synthesized by various dosage of graphite oxide (GO) and hydrofluoric acid (HF) during a facile solvothermal process successfully. The... more
A series of GnTiO2 {001} nanocomposites (GTN) with dominate exposed {001} facets has been synthesized by various dosage of graphite oxide (GO) and hydrofluoric acid (HF) during a facile solvothermal process successfully. The photocatalytic degradation efficiency (PDE) of the optimal sample reached up to 98.7% for liquids methyl orange and up to 78.6% for gaseous toluene under the UV-light irradiation for 30min, which is much higher than P25. The effects mechanism of HF and GO on the percentage of {001} facets exposed and the crystal morphology are investigated by XRD, SEM, TEM, UV-Vis, XPS and BET measurement, particularly. Cyclic voltammograms (CV) and electrochemical impedance spectroscopy (EIS) were used to explore the electron transfer mechanisms of GnTiO2 {001} nanocomposites. These results reveal the enhanced photocatalytic properties attribute to the excellent electron transport of Gn and highly reactive {001} facets can facilitate the separation of photo-generated charge carriers. Moreover, Gn can extend the absorption range of light and improve the adsorptivity of pollutant molecules.
Research Interests:
ABSTRACT Chrysanthemum-like brookite TiO2 nanostructures were synthesized via a hydrothermal method in the presence of cetyltrimethylammonium bromide (CTAB). TiCl4 was used as the titanium source, and sodium hydroxide was used to control... more
ABSTRACT Chrysanthemum-like brookite TiO2 nanostructures were synthesized via a hydrothermal method in the presence of cetyltrimethylammonium bromide (CTAB). TiCl4 was used as the titanium source, and sodium hydroxide was used to control pH value. The morphology and structure of the as-prepared TiO2 powders were characterized using X-ray diffraction (XRD), Raman spectroscopy (RS), field emission scanning electron microscope (FESEM), and Transmission electron microscopy (TEM). The results indicated that brookite TiO2 with chrysanthemum-like nanostructures of about 3 µm in diameter were composed of numerous curved petals in size of hundreds of nanometers in length and 60–80 nm in thickness. The chrysanthemum-like TiO2 nanostructures were applied to the photodegradation of methylene blue under UV light illumination and showed high photocatalytic activity to methylene blue (10 mg L−1 methylene blue (MB) solution: 86% degradation) at 10 mW cm−2.
Research Interests:
ABSTRACT Flower-like and corn-like CuO nanostructures composed of CuO nanoparticles were successfully synthesized via ultrasound-assisted template method, respectively, by controlling the initial concentration of Cu(NO3)2 solution. Here,... more
ABSTRACT Flower-like and corn-like CuO nanostructures composed of CuO nanoparticles were successfully synthesized via ultrasound-assisted template method, respectively, by controlling the initial concentration of Cu(NO3)2 solution. Here, cotton fibers were used as template agent. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM) and energy-dispersive spectroscopy (EDS), respectively. The results demonstrated that the initial concentration of Cu(NO3)2 solution was an important parameter for determining whether CuO nanoparticles assembled into flower-like structures or corn-like structures. The mechanism of forming different nanostructures of CuO was discussed.
Research Interests:
Research Interests:
ABSTRACT Nano-ZnO assembled cotton fibers, with excellent UV blocking property and good water-wash durability, have been successfully fabricated using microwave assisted precipitation and crystallization process synchronously in situ for... more
ABSTRACT Nano-ZnO assembled cotton fibers, with excellent UV blocking property and good water-wash durability, have been successfully fabricated using microwave assisted precipitation and crystallization process synchronously in situ for the first time. Here, zinc nitrate hexahydrate was used as zinc resource and sodium hydroxide was used as precipitate. The asobtained samples were characterized by powder X-ray diffractometer (XRD), filed emission scanning electron microscopy (FESEM), and energy-dispersive spectrometry (EDS), UV/Visible spectroscopy and Fourier transformation infrared spectroscopy (FTIR). Wurtzite ZnO with about 30–40 nm in diameter was fabricated in the lumen as well as in mesoporous structures of cotton fibers. The as-prepared samples have excellent UV absorbing activity over a broad range in the region from 225 nm to 380 nm. The crystallinity and UV blocking properties keep unchangeable as the former after being washed for 60 min in 33 l water. FTIR results reveal that there is no peak shift and new peak occurred, which indicates that no chemical bond exist between nano-ZnO and cotton fibers. Mechanical force is the only way to bond nano-ZnO to cotton fibers in the experimental condition. ZnO nanoparticles and wax existing in cotton fibers can combine to a firmly hybrid layer in the surface and the inner of cotton fibers during microwave treatment, which may bring the good water-wash durability.
Research Interests:
ABSTRACT Simonkolleite (Zn5(OH)8Cl2·2H2O) nanodisks with a width of 40 nm have been successfully synthesized via a hydrothermal method using zinc chloride and ammonia as the starting materials. The conversion mechanisms from simonkolleite... more
ABSTRACT Simonkolleite (Zn5(OH)8Cl2·2H2O) nanodisks with a width of 40 nm have been successfully synthesized via a hydrothermal method using zinc chloride and ammonia as the starting materials. The conversion mechanisms from simonkolleite nanodisks to ZnO spindles under hydrothermal condition and to ZnO nanotablets under solid phase transformation were discussed respectively. The simonkolleite nanodisks obviously occur in hydrothermal system with the combination of a lower alkalinity, lower temperature (
Research Interests:
Research Interests:
Under mild reaction conditions, cinnamaldehyde was reduced to cinnamyl alcohol with high selectivity and conversion using nano-LiH or nano-NaH as a reducing agent. Selectivity of 99.8% was obtained as reduced by nano-LiH with conversion... more
Under mild reaction conditions, cinnamaldehyde was reduced to cinnamyl alcohol with high selectivity and conversion using nano-LiH or nano-NaH as a reducing agent. Selectivity of 99.8% was obtained as reduced by nano-LiH with conversion of 99.4% in short reaction ...
Research Interests:
ABSTRACT The performance of the LaBaCuFeO5+δ–Ce0.8Sm0.2O1.9 (LBCF–SDC) composite cathodes was studied in this paper. Electrical conductivity, thermal expansion and electrochemical properties were investigated by four probing DC technique,... more
ABSTRACT The performance of the LaBaCuFeO5+δ–Ce0.8Sm0.2O1.9 (LBCF–SDC) composite cathodes was studied in this paper. Electrical conductivity, thermal expansion and electrochemical properties were investigated by four probing DC technique, dilatometry, AC impedance and polarization techniques, respectively. The thermal expansion coefficients of the LBCF–SDC were between (16.3 and 13.4) × 10−6 K−1 from 30 to 850 °C, which was lower value than LBCF (17.0 × 10−6 K−1). AC Impedance spectroscopy measurements of LBCF–SDC/SDC/LBCF–SDC test cell were carried out. Polarization resistance values for the LBCF–SDC10 cathode was as low as 0.097 Ω cm2 at 750 °C.
Research Interests:
... assembled cotton fibers via a two-step hydrothermal method Yan Li Yunling Zou Yanyan Hou ... J Colloid Interface Sci 298: 787793 Paul R, Bautista L, Varga MDL, Botet JM, Casals E, Puntes V, Marsal F (2010) Nano-cotton fabrics... more
... assembled cotton fibers via a two-step hydrothermal method Yan Li Yunling Zou Yanyan Hou ... J Colloid Interface Sci 298: 787793 Paul R, Bautista L, Varga MDL, Botet JM, Casals E, Puntes V, Marsal F (2010) Nano-cotton fabrics with high ultraviolet protection. ...
Research Interests:
Research Interests:
ABSTRACT Nano-ZnO assembled cotton fibers (NZCF) with excellent antibacterial properties were fabricated using microwave synthesis method. The effects of ZnO size, ZnO content, assembly times, microwave power and Zn2+ concentration of the... more
ABSTRACT Nano-ZnO assembled cotton fibers (NZCF) with excellent antibacterial properties were fabricated using microwave synthesis method. The effects of ZnO size, ZnO content, assembly times, microwave power and Zn2+ concentration of the synthesis solution on the antibacterial activity of the NZCF were studied using bacteriological tests such as Petri dish and agar diffusion method. The results show that NZCF has the antibacterial circle width (ACW) of about 1.5–2.3 mm and 2.3–3.4 mm against Escherichia coli (E. coli, gram-positive organism) and Staphylococcus aureus (S. aureus, gram-negative organism), respectively. It is also found that the antibacterial activity of NZCF increases with decreasing ZnO size, increasing ZnO content in NZCF and increasing Zn2+ concentration in synthesis solution.
Research Interests:
The cellulolytic fungus Trichoderma reesei was used to prepare cellulose nanowhiskers (CNW) by controlled hydrolysis of microcrystalline cellulose (MCC). The penetration of fungus into the ordered regions of MCC resulted in reduction... more
The cellulolytic fungus Trichoderma reesei was used to prepare cellulose nanowhiskers (CNW) by controlled hydrolysis of microcrystalline cellulose (MCC). The penetration of fungus into the ordered regions of MCC resulted in reduction (10%) of its crystallinity. The zeta ...