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A series of CuCe0.75Zr0.25Ox catalysts (CCZ) were synthesized based on the environmental‐friendly bacterial cellulose (BC) by using the sol‐gel method. The corresponding synthesis mechanism, physicochemical properties of the catalysts and catalytic performances for toluene oxidation were comprehensively studied. In the presence of BC without sugar, the CCZ−A synthesized by ethanol‐gel exhibits better catalytic activity than the CCZ−W synthesized by water‐gel, which may be due to the different roles of BC in different solvents. However, it is worth noting that the graft copolymerization between BC and active metal (Ce4+, Cu2+) is the same process in both water‐gel and ethanol‐gel. The activity of CCZ‐SW synthesized by water‐gel using BC with sugar is obviously higher than that of CCZ−W and CCZ−A. The temperature of complete degradation of toluene over CCZ‐SW is 205 °C, which is 35 °C lower than that of CCZ−W. The results from BET, Raman and H2‐TPR indicate that the larger the specific surface area, the more oxygen vacancies and better low‐temperature reducibility, that are mainly responsible for the excellent activity of CCZ‐SW. The existence of sugar in BC could hinder the agglomeration of active metal particles during the calcination process. Combined with the results of in situ DRIFT, the adsorbed toluene on the catalyst surface is oxidized into alkoxide, aldehydic and carboxylic acid species as intermediates before the complete oxidation into CO2 and H2O. [ABSTRACT FROM AUTHOR]

Al–Ni co-doped ZnO (NiAl:ZnO) thin films were deposited on glass substrates using a sol–gel method. Based on a previous study, Zn 1 − x Al x O (AZO; Al/Zn = 1.5 mol%) thin films optimized with a Ni content of 0.5 mol% were annealed at different temperatures from 450 to 600 °C in N 2 /H 2 (95/5) forming gas for 1 h. The effects of the annealing temperature on the structural, electrical and optical properties were determined. X-ray diffraction showed that NiAl:ZnO thin film annealed at 500 °C exhibited the best crystallization quality. XPS revealed the presence of metallic Ni and Ni 2 O 3 states, as well as Ni and Al atoms were successfully doped in NiAl:ZnO films, which did not result in a change in ZnO crystal structure and orientation. Scanning electron microscopy showed that the films were smooth and compact, and the grain size increased with increasing annealing temperature from ~ 23.8 nm to ~ 34.6 nm. According to the Hall Effect measurements, when the temperature reached 500 °C, the resistivity of the thin film showed the lowest value of 1.05 × 10 − 3 (Ω cm), which is the lowest resistivity reported for NiAl:ZnO films. The UV–Vis transmission spectra showed a high transmittance of more than 80% in the visible light range, and the band gap of the films was increased from 3.30 to 3.55 eV. This study showed that the annealing temperature in the forming gas is a vital factor affecting the quality of thin films. In addition, 500 °C was found to be the most appropriate annealing temperature for NiAl:ZnO films. This study provides a simple and efficient method for preparing high quality, high transparency and low resistivity NiAl:ZnO films for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Abstract: Highly transparent Cu2O-doped p-type Zn1−x Al x O (AZO; Al/Zn=1.5at%) conducting oxide films were synthesized on glass substrates using a cost effective low temperature sol–gel method. X-ray diffraction of the Cu2O-doped AZO (AZO:Cu2O) films revealed a polycrystalline Cu2O (110) peak. The I–V measurements of the p–n junction (ITO/AZO:Cu2O) revealed rectifying I–V characteristics, showing that these AZO:Cu2O films exhibit p-type conductivity. p-Type conductivity was achieved by annealing the AZO:Cu2O films in N2/H2 forming gas at 400°C. The hole concentration, hole mobility and resistivity of the 0.5–2mol% AZO:Cu2O films were 5.41×1018 to 1.99×1020 cm−3, 8.36–21.6cm2/Vs and 1.66×10−2 to 6.94×10−3 Ωcm, respectively. These results show that post-annealing in a forming gas is effective and practicable in producing p-type AZO. [Copyright &y& Elsevier]

Abstract: NiO-doped p-type AZO (Al/Zn=1.5at.%) films were synthesized on glass substrates using a simple and low cost sol–gel solution method. p-type conductivity could be achieved by annealing the NiO:AZO films in N2/H2 forming gas at 550°C. The real Al/Zn and Ni/Zn ratio, hole concentration, hole mobility and resistivity of the 1.5–2mol% NiO-doped AZO films were 0.26–0.29, 0.06–0.09, 3.15×1018–2.18×1020 cm−3, 2.33–12.76cm2/Vs, and 2.39×10−1–1.24×10−2 Ωcm, respectively. I–V measurements of the p–n junction (ITO/NiO:AZO) revealed rectifying I–V characteristics, confirming that these NiO:AZO films exhibit p-type conductivity. This study opens the possibility of developing highly conductive p-type composite transparent conducting oxides for optoelectronic devices. [Copyright &y& Elsevier]

Abstract: Li-doped NiO thin films (Li:NiO) were deposited on glass substrates using a facile sol–gel method. The effects of Li doping concentration on the structural, electrical and optical properties of Li:NiO films were examined. The structural properties of Li:NiO films were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy. XRD revealed the Li:NiO films to have a polycrystalline bunsenite structure. The surface morphology of the Li:NiO films exhibited nanocrystalline grains with a randomly oriented morphology. The resistivity decreased substantially to 1.33kΩcm at 0.11mol%, which is one order of magnitude lower than that of the undoped NiO film. The mean transmittance decreased from 70% to 60% with increasing Li doping concentration from 0.02mol% to 0.19mol%. [Copyright &y& Elsevier]