abstract
This work studies the variation in the photocatalytic properties of CdS derived from the insertion of In, Ga, Ag-In and Ag-Ga in the CdS lattice through solvothermal methodology. Solvothermal synthesis of CdS-M photocatalysts has been succesful for the insertion of Ga3+, In3+, Ga3+/Ag+ and In3+/Ag+ into the hexagonal crystal lattice of one-dimensional CdS. The insertion of In, Ga, Ag-In and Ag-Ga modifies the band gap and the relative position of EVB. CdS modified with In3+ or Ga3+ shows an increase in the band gap and upshift in the relative position of the valence band energy which leads to a low efficiency hydrogen production. The co-addition of Ag+-In3+ or Ag+-Ga3+ favours the insertion of Ag+ ions into the CdS lattice with narrower band gap. Of all the co-substituted photocatalysts, the CdS-AgGa was the only one that showed a higher photoactivity with respect to the CdS. The increase in the photoactivity of the CdS-AgGa photocatalyst is related to the band gap narrowing and downshift in the relative position of the valence band energy which enhance their visible light absorption and potential for oxidation. The CdS-AgGa photocatalyst shows small segregation of metallic Ag nanoparticles at the surface which also assist in the photoactivity of the sample. © 2018 Elsevier Ltd
keywords
Binary alloys; Cadmium sulfide; Energy gap; Gallium; Hydrogen; Hydrogen production; II-VI semiconductors; Indium; Light absorption; Nanorods; Photocatalysis; Silver; Surface segregation; Valence bands; Hexagonal crystals; Photocatalytic property; Relative positions; Solvothermal; Solvothermal method; Solvothermal synthesis; Visible light absorption; Water splitting; Silver nanoparticles
authors
Soto, E; Vaquero, F; Mota, N; Fateixa, S; Trindade, T; Navarro, RM; Fierro, JLG
our authors
Sara Fateixa
Post-Doc Fellowship
Tito Trindade
Full professoracknowledgements
The present work was performed within the research program supported by MINECO (Spain) under the project CTQ2016-76505-C3-1-R and CAM within the S2013/MAE-288 project. E. Soto would like to acknowledge MINECO for the FPI research grants. Appendix A