Simultaneous Conduction and Valence Band Regulation of Indium-Based Quantum Dots for Efficient H2 Photogeneration

Optimizing the Synthetic Conditions of "Green" Colloidal AgBiS2 Nanocrystals Using a Low-Cost Sulfur Source

Colloidal AgBiS₂ nanocrystals (NCs) have attracted increasing attention as a near-infrared absorbent materials with non-toxic elements and a high absorption coefficient. In recent years, colloidal AgBiS₂ NCs have typically been synthesized via the hot injection method using hexamethyldisilathiane (TMS) as the sulfur source. However, the cost of TMS is one of the biggest obstacles to large-scale synthesis of colloidal AgBiS₂ NCs. Herein, we synthesized colloidal AgBiS₂ NCs using oleylamine@sulfur (OLA-S) solution as the sulfur source instead of TMS and optimized the synthesis conditions of colloidal AgBiS₂ NCs. By controlling the reaction injection temperature and the dosage of OLA-S, colloidal AgBiS₂ NCs with adjustable size can be synthesized. Compared with TMS-based colloidal AgBiS₂ NCs, the colloidal AgBiS₂ NCs based on OLA-S has good crystallinity and fewer defects.

Sulfide-Based Photocatalysts Using Visible Light, with Special Focus on In2S3, SnS2 and ZnIn2S4

Sulfides are frequently used as photocatalysts, since they absorb visible light better than many oxides. They have the disadvantage of being more easily photocorroded. This occurs mostly in oxidizing conditions; therefore, they are commonly used instead in reduction processes, such as CO2 reduction to fuels or H2 production. Here a summary will be presented of a number of sulfides used in several photocatalytic processes; where appropriate, some recent reviews will be presented of their behaviour. Results obtained in recent years by our group using some octahedral sulfides will be shown, showing how to determine their wavelength-dependent photocatalytic activities, checking their mechanisms in some cases, and verifying how they can be modified to extend their wavelength range of activity. It will be shown here as well how using photocatalytic or photoelectrochemical setups, by combining some enzymes with these sulfides, allows achieving the photo-splitting of water into H2 and O2, thus constituting a scheme of artificial photosynthesis.