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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]

The silica sphere-plate interaction forces in zirconia nanoparticle suspensions have been successfully measured to explain how negligibly charged silica microspheres can be stabilized through the addition of highly charged zirconia nanoparticles. However, the influence of nanoparticle volume fraction on the stabilization as well as how various forces (the attractive van der Waals force, repulsive electrostatic force, and depletion force) contribute to the total interaction force still remains unclear. Therefore, an effective zeta potential fitting model is developed to explain the experimental interaction force curves based on a variable effective Debye length and a measured effective zeta potential using a continuum assumption. [ABSTRACT FROM AUTHOR]

Highlights: [•] LiNi0.5Sm x Mn1.5−x O4 (x =0, 0.01, 0.03, and 0.05) spinel have been synthesized. [•] The Sm-doping improves the spinel structural stability. [•] LiNi0.5Sm x Mn1.5−x O4 exhibit enhanced cycling stability and rate performance. [•] LiNi0.5Sm x Mn1.5−x O4 display low charge transfer impedance. [ABSTRACT FROM AUTHOR]

Abstract: Spinel cobalt oxide (Co3O4) nanowires grown on Ni foam are successfully synthesized using a novel microwave-assisted template-free method. The effect of reaction temperature, concentration of reactants, and reaction time on the morphology and crystalline structures of the prepared nanowires is studied. The present work has demonstrated that uniform Co3O4 nanowires with diameters of 500–580nm and lengths of 6–8μm can be synthesized under proper reaction condition. Moreover, the proposed microwave-assisted template-free method can significantly reduce reaction time, increase reaction efficiency, and provide better control over the geometry of the nanostructures. [Copyright &y& Elsevier]

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]

Highlights: [•] 3D Co(II) ions modified graphene aerogels were prepared by one-step hydrothermal process. [•] The aerogel electrodes showed hybrid supercapacitor behaviors. [•] The aerogel electrodes exhibited high rate capability and long-term cycling stability. [Copyright &y& Elsevier]

Abstract: Anatase TiO2 nanotubes grown on Ni foam substrates were successfully synthesized by treating TiO2 nanocrystals coated on an Ni foam in alkaline solution using a facile microwave-assisted hydrothermal method. The as-synthesized TiO2 nanotubes were characterized by SEM, TEM, and XRD. The effects of NaOH concentration, reaction time, hydrothermal temperature, and calcination temperature on the morphology, as well as crystal structure, of the nanotubes were investigated. TiO2 nanotubes synthesized under the optimal conditions were polycrystalline anatases with 4 to 5 multilayers, approximately 10nm wide, and several tens of nanometers long. The possible formation mechanism for TiO2 nanotubes was also discussed in the current paper. [Copyright &y& Elsevier]

Highlights: [•] Surface reaction plays the major role in O3/MnO x /SBA-15 for the removal of oxalic acid. [•] MnO x /SBA-15 benefits adsorption of oxalic acid and initiation of hydroxyl radicals. [•] Protonated surface hydroxyl groups are claimed to be the main active centers. [•] Multivalent MnO x with higher oxidation states contribute to electron transfer. [•] A possible mechanism of catalytic ozonation is proposed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Spinel LiNi0.5Mn1.5O4 was synthesized by gelatin-assisted method. [•] Moderate amount of gelatin optimize the spinel structure and morphology. [•] LNMO-6 cathode exhibits enhanced cycling stability and rate performance. [•] LNMO-6 cathode displays smaller interface impedance including RSEI and Rct. [ABSTRACT FROM AUTHOR]