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

Abstract

Indium-based chalcogenide semiconductors have been served as the promising candidates for solar H2 evolution reaction, however, the related studies are still in its infancy and the enhancement of efficiency remains a grand challenge. Here, we report that the photocatalytic H2 evolution activity of quantized indium chalcogenide semiconductors could be dramatically aroused by the co-decoration of transition metal Zn and Cu. Different from the traditional metal ion doping strategies which only focus on narrowing bandgap for robust visible light harvesting, the conduction and valence band are coordinately regulated to realize the bandgap narrowing and the raising of thermodynamic driving force for proton reduction, simultaneously. Therefore, the as-prepared noble metal-free Cu0.4-ZnIn2S4 quantum dots (QDs) exhibits extraordinary activity for photocatalytic H2 evolution. Under optimal conditions, the Cu0.4-ZnIn2S4 QDs could produce H2 with the rate of 144.4 μmol h−1 mg−1, 480-fold and 6-fold higher than that of pristine In2S3 QDs and Cu-doped In2S3 QDs counterparts respectively, which is even comparable with the state-of-the-art cadmium chalcogenides QDs.

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

“…The average diameters of TMS–based and OLA–S–based colloidal AgBiS 2 NCs are about 4.3 ± 1.6 nm ( Figure S2a ) and 7.8 ± 1.9 nm ( Figure S2b ), respectively. High–resolution TEM (HR–TEM) images of spherical colloidal AgBiS 2 NCs based on TMS and OLA–S are shown in Figure 2 b,c [ 50 , 51 , 52 ]. Lattice spacing of about 0.32 nm, corresponding to (111) crystal plane spacing of cubic rock salt structure AgBiS 2 , can be clearly seen, which is consistent with the XRD results above.…”

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

“…It is frequently used as buffer layer in thin film photovoltaic cells. It has been used for H 2 photoproduction in works beginning 15 years ago [113][114][115]. Its use for aqueous organics photodegradation is also relatively old [116][117][118].…”

Surface Morphology and Electrical Conductivity of In2S3 thin films Doped with Copper

“…11, the maximum value of the current density as a function of voltage has been calculated at temperatures 70℃ for 𝛼 = 1.1 [19,20]. The band gap is generally changed by the doping of Cu, and could cause to transport enhancement Therefore, the doping of Cu makes the main role for the band gap narrowing [21,22].…”