Effect of Titania Regular Macroporosity on the Photocatalytic Hydrogen Evolution on Cd1−xZnxS/TiO2Catalysts under Visible Light

Semiconductor photocatalysts and mechanisms of carbon dioxide reduction and nitrogen fixation under UV and visible light

The review summarizes the current knowledge about heterogeneous semiconductor photocatalysts that are active towards photocatalytic reduction of carbon dioxide and molecular nitrogen under visible and near-UV light. The main classes of these photocatalysts and characteristic features of their application in the target processes are considered. Primary attention is given to photocatalysts based on titanium dioxide, which have high activity and stability in the carbon dioxide reduction. For the first time, the photofixation of nitrogen under irradiation in the presence of various semiconductor materials is considered in detail.

The bibliography includes 264 references.

Composite photocatalysts based on Cd1−xZnxS and TiO2 for hydrogen production under visible light: effect of platinum co-catalyst location

Ternary composite photocatalysts based on titania and solid solutions of CdS and ZnS were prepared and studied by a set of physicochemical methods including XRD, XPS, HRTEM, UV-vis spectroscopy, and electrochemical tests. Two synthetic techniques of platinization of Cd_1−xZn_xS/TiO₂ were compared. In the first case, platinum was deposited on the surface of synthesized Cd_1−xZn_xS (x = 0.2–0.3)/TiO₂ P25; in the second one, Cd_1−xZn_xS (x = 0.2–0.3) was deposited on the surface of Pt/TiO₂ P25. The photocatalytic properties of the obtained samples were compared in the hydrogen evolution from TEOA aqueous solution under visible light (λ = 425 nm). The Cd_1−xZn_xS (10–50 wt%; x = 0.2–0.3)/Pt (1 wt%)/TiO₂ photocatalysts demonstrated much higher photocatalytic activity than the Pt (1 wt%)/Cd_1−xZn_xS (10–50 wt%; x = 0.2–0.3)/TiO₂ ones. It turned out that the arrangement of platinum nanoparticles precisely on the titanium dioxide surface in a composite photocatalyst makes it possible to achieve efficient charge separation according to the type II heterojunctions and, accordingly, a high rate of hydrogen formation. The highest photocatalytic activity was demonstrated by 20% Cd_0.8Zn_0.2S/1% Pt/TiO₂ in the amount of 26 mmol g⁻¹ h⁻¹ (apparent quantum efficiency was 7.7%) that exceeds recently published values for this class of photocatalysts.

The determination of the preferred location of platinum particles in TiO₂–Cd_1−xZn_xS systems was carried out for the first time.

Amorphous MoS2 decorated on uniform Cd0.8Zn0.2S microspheres with dramatically improved photocatalytic hydrogen evolution performance

A series of Cd_1−xZn_xS solid solutions and samples of amorphous MoS₂ decorated on Cd_1−xZn_xS microspheres were successfully prepared.

Synthesis of Cd1−xZnxS photocatalysts for gas-phase CO2 reduction under visible light

Gas-phase CO₂ reduction with H₂O on Cd_1−xZn_xS-based photocatalysts has been performed for the first time.

Nanostructured silver sulfide: synthesis of various forms and their application

The results of experimental studies on nanostructured silver sulfide are analyzed and generalized. The influence of small particle size on nonstoichiometry of silver sulfide is discussed. Methods for the synthesis of various forms of nanostructured Ag2S including nanopowders, stable colloidal solutions, quantum dots, core – shell nanoparticles and heteronanostructures are described. The advantages and drawbacks of different synthetic procedures are analyzed. Main fields of application of nanostructured silver sulfide are considered.

The bibliography includes 184 references.

Achieving photocatalytic hydrogen production from alkaline solution upon a designed mesoporous TiO2–Ni hybrid employing commonly used paper as a sacrificial electron donor

Photocatalytic hydrogen evolution from water splitting, using paper as an electron donor, was achieved upon use of a hybrid photocatalyst of mesoporous TiO₂ decorated with Ni nanoparticles.