Han, Sangmoon Noh, Siyun Yu, Yeon-Tae Lee, Cheul-Ro Lee, Seoung-Ki Kim, Jin Soo 2024-01-19T16:01:27Z 2024-01-19T16:01:27Z 2022-01-25 2020-12 1944-8244 https://pubs.kist.re.kr/handle/201004/117710 In the present study, we have achieved high-performance photoelectrochemical water splitting (PEC-WS) using GaN nanowires (NWs) coated with tungsten sulfide (WxS1-x) (GaN-NW-WxS1-x) as a photoanode. The measured current density and applied-bias photon-to-current efficiency were 20.38 mA/cm(2) and 13.76%, respectively. These values were much higher than those reported previously for photoanodes with any kind of III-nitride nanostructure. The amount of hydrogen gas formed was 1.01 mmol/cm(2) from 7 h PEC-WS, which was also much higher than the previously reported values. The drastic improvement in the PEC-WS performance using the GaN-NW-WxS1-x photoanode was attributed to an increase in the number of photogenerated carriers due to the highly crystalline GaN NWs, and acceleration of separation of photogenerated carriers and consequent suppression of charge recombination because of nitrogen-terminated surfaces of NWs, sulfur vacancies in WxS1-x, and type-II band alignment between NW and WxS1-x. The degree of impedance matching, evaluated from Nyquist plots, was considered to analyze charge transfer characteristics at the interface between the GaN-NW-WxS1-x photoanode and 0.5-M H2SO4 electrolyte. Considering the material system and scheme for the PEC-WS, our approach provides an efficient way to improve hydrogen evolution reaction. English American Chemical Society Highly Efficient Photoelectrochemical Water Splitting Using GaN-Nanowire Photoanode with Tungsten Sulfides Article 10.1021/acsami.0c17811 1 ACS Applied Materials & Interfaces, v.12, no.52, pp.58028 - 58037 ACS Applied Materials & Interfaces 12 52 58028 58037 N scie scopus 000605187100034 2-s2.0-85098794660 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article SOLAR HYDROGEN-PRODUCTION VISIBLE-LIGHT HIGH-PERFORMANCE COLLOIDAL SYNTHESIS PURE WATER ARRAYS GENERATION CELLS NANOSHEETS 1T-WS2 photoelectrochemical water splitting GaN nanowire WxS1-x photoanode hydrogen gas