Wide Band Gap CuGa(S,Se)2 Thin Films on Transparent Conductive Fluorinated Tin Oxide Substrates as Photocathode Candidates for Tandem Water Splitting Devices
| Autor: | Kimberly Horsley, Alexander D DeAngelis, Nicolas Gaillard |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Photocurrent
Materials science business.industry Annealing (metallurgy) Wide-bandgap semiconductor 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Tin oxide 01 natural sciences Photocathode 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials General Energy Water splitting Optoelectronics Reversible hydrogen electrode Physical and Theoretical Chemistry Thin film 0210 nano-technology business |
| Zdroj: | The Journal of Physical Chemistry C. 122:14304-14312 |
| ISSN: | 1932-7455 1932-7447 |
| Popis: | The purpose of this work was to explore the potential of CuGa(S,Se)2 thin films as wide-EG top cell absorbers for photoelectrochemical (PEC) water splitting. A synthesis was developed on fluorinated tin oxide (FTO) photocathodes by converting copper-rich co-evaporated CuGaSe2 into CuGa(S,Se)2 via a post-deposition annealing. We found it necessary to first anneal CuGaSe2 at low-temperature in sulfur then at high-temperature in nitrogen to preserve the transparency and conductivity of the FTO. Using this two-step synthesis, we fabricated a 1.72 eV CuGa(S,Se)2 photocathode with a saturation current density and photocurrent onset potential of 10 mA/cm2 and −0.20 V versus reversible hydrogen electrode, respectively. However we found that the PEC performance and sub-EG transmittance, worsened with increasing copper content. Using flatband potential measurements and the Gerischer model, we show that divergences in PEC performance of CuGa(S,Se)2 photocathodes can be explained by differences in conduction band min... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|