| Full text | |
| Author(s): |
Araujo, Mileny dos Santos
;
dos Santos, Hugo Leandro Sousa
;
Medina, Marina
;
Salomao, Arthur Corrado
;
Mascaro, Lucia Helena
;
Andrade Junior, Marcos Antonio Santana
Total Authors: 6
|
| Document type: | Journal article |
| Source: | Electrochimica Acta; v. 464, p. 7-pg., 2023-10-01. |
| Abstract | |
Cu2ZnSn(S,Se)4 (CZTSSe) is a promising material as a photocathode for photoelectrochemical (PEC) water splitting because it is inexpensive and composed of earth-abundant elements. However, it has a high density of deep defects, such as CuZn and ZnCu antisites, which is pointed out as the main cause of band tailing and low onset potential-based PEC devices. By substituting 10% of Cu+ by Ag+, the onset potential shifts positively from 0.2 to 0.4 VRHE, the photocurrent is almost three-folded, and solar-to-hydrogen efficiency is 6 times higher than that for the Ag-free photocathode. Absolute intensity photoluminescence (AIPL) in different light intensities was used to demonstrate that the Ag-substitution vanquishes the Cu/Zn-related defects. The quasi-Fermi level splitting (QFLS) values are obtained fitting the Katahara-modified model of the Planck Law, and the curve QFLS versus light intensity provides the quasi-Fermi Level pinning. The low QFLS pinning for CZTSSe indicates midgap states act as recombination centers, which are detrimental to the photocathode. The increased QFLS pinning for ACZTSSe evidence that Ag-partial substitution vanquishes the Cuzn-related defects, decreasing recombination, enhancing the charge carriers transport, and consequently, improving the hydrogen production. (AU) | |
| FAPESP's process: | 17/15144-9 - Metal-doped chalcogenides for application in intermediate band solar cells |
| Grantee: | Marcos Antonio Santana Andrade Junior |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 17/11986-5 - Generation and storage of New Energy: bringing technological development for the country |
| Grantee: | Ana Flávia Nogueira |
| Support Opportunities: | Research Grants - Research Centers in Engineering Program |
| FAPESP's process: | 19/26860-2 - Synthesis and modification of CuO/Ga2O4 and Cu2O/Ga2O4 nanostructured films applied in H2 production from water photoelectrochemical reduction of water |
| Grantee: | Hugo Leandro Sousa dos Santos |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 14/50249-8 - Green chemistry: sustainable synthetic methods employing benign solvents, safer reagents, and bio-renewable feedstock |
| Grantee: | Arlene Gonçalves Corrêa |
| Support Opportunities: | Research Grants - Research Centers in Engineering Program |
| FAPESP's process: | 13/07296-2 - CDMF - Center for the Development of Functional Materials |
| Grantee: | Elson Longo da Silva |
| Support Opportunities: | Research Grants - Research, Innovation and Dissemination Centers - RIDC |
| FAPESP's process: | 17/12794-2 - Synthesis, characterization and application of MoS2 and WS2 films in photoelectrocatalysis for hydrogen production |
| Grantee: | Marina Medina da Silva |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 20/09000-7 - High efficient chalcogenide thin film devices for solar-to-fuel conversion |
| Grantee: | Arthur Corrado Salomão |
| Support Opportunities: | Scholarships in Brazil - Scientific Initiation |