Strong thickness dependence in thin film photocatalytic heterojunctions: the ZnO-BiO case study.

Semiconductor heterojunctions are an effective way to achieve efficient photocatalysts, as they can provide an adequate redox potential with visible light excitation. Several works have reported synergistic effects with nanoparticle semiconductor materials. The question is still open for thin film heterojunctions formed by stacked layers, as photocatalysis is considered a surface phenomenon.

Synergistic photocatalytic effect of BiOBr-BiOI heterojunctions due to appropriate layer stacking.

The increasing interest in acquiring efficient visible-light active photocatalytic materials has led to the formation of heterojunctions with different combinations of semiconductors. Despite the fact that increasingly more complex structures are proposed, there are still many unclear factors affecting their performance and limiting their prompt implementation. In this work, we used the spray pyrolysis technique to deposit individual visible light-active BiOBr and BiOI films and formed the heterojunctions BiOBr-BiOI and BiOI-BiOBr to determine the effect of the stacking order of semiconductors.

The bismuth oxyhalide family: thin film synthesis and periodic properties.

Bismuth oxyhalides (BiOX, where X = F, Cl, Br, I) are interesting materials due to their layered structure, which can be useful for different applications. In this work, we present the synthesis of the complete BiOX family in the thin film form. The tetragonal phase Bi2O3 film deposited onto a glass substrate was transformed into BiOF, BiOCl or BiOBr by a simple immersion at ambient temperature in a halide (X = F, Cl, Br) containing solution.

Effect of 2,6-Bis-(1-hydroxy-1,1-diphenyl-methyl) Pyridine as Organic Additive in Sulfide NiMoP/γ-Al₂O₃ Catalyst for Hydrodesulfurization of Straight-Run Gas Oil.

The effect of 2,6-bis-(1-hydroxy-1,1-diphenyl-methyl) pyridine (BDPHP) in the preparation of NiMoP/γ-Al₂O₃ catalysts have been investigated in the hydrodesulfurization (HDS) of straight-run gas oil. The γ-Al₂O₃ support was modified by surface impregnation of a solution of BDPHP to afford BDPHP/Ni molar ratios (0.5 and 1.

Preparation of efficient cadmium sulfide nanofibers for hydrogen production using ethylenediamine (NH2CH2CH2NH2) as template.

The preparation of CdS was performed by the precipitation method using ethylenediamine as template and tetrahydrofuran, acetonitrile or butanol as organic solvents. The formation of CdS with hexagonal structure was observed by XRD due to the template effect. FTIR studies showed that the amount of the template linked to the surface of the CdS depends on the organic solvent used.

Photoconversion of 4-nitrophenol in the presence of hydrazine with AgNPs-TiO2 nanoparticles prepared by the sol-gel method.

The photocatalytic properties of functionalized TiO2 with silver nanoparticles (AgNPs) for the conversion of 4-nitrophenol to 4-aminophenol in the presence of hydrazine were investigated. The TiO2 semiconductor synthesized by the sol-gel method was functionalized with AgNPs at different loadings, and their structural and optical properties were characterized by several techniques. The functionalized TiO2 with 1.

Photocatalytic hydrogen production by water/methanol decomposition using Au/TiO2 prepared by deposition-precipitation with urea.

Gold nanoparticles deposited on TiO2 Degussa P25, prepared by deposition-precipitation with urea, were studied in the photocatalytic hydrogen production. The effect of parameters such as mass of catalyst, gold loading, thermal treatment, and atmosphere of treatment was evaluated and optimized. The presence of metallic gold on the titania surface showed to have contributed to the high improvement in the activity of bare TiO2 for hydrogen generation under UV light (λ=254 nm) using a lamp of low energy (2W) consumption.