Ecofriendly AgBiS<sub>2</sub> Nanocrystal Photoanode for Highly Efficient Visible-Light-Driven Photoelectrochemical Water Splitting
Taiho Park, Gisang Park, Sung Yong Bae, Hae Jeong Kim, Duck Hoon Lee, Seonkyung Ko, Soo‐Kwan Kim, Gyudong Lee, Hyung Ryul You, Hyosung Choi, Jong‐Sung Yu, Younghoon Kim, Jongmin Choi
Abstract
Photoelectrochemical (PEC) hydrogen production via water splitting is a promising sustainable energy conversion method. However, most semiconductors used as photoanodes in PEC splitting exhibit several drawbacks, including ultraviolet (UV)-limited activity, toxic components, and complicated material processing. To address these issues, this study presents a photoanode design strategy for visible-light-driven PEC water splitting in aqueous Na 2 SO 4 solution using a solution-processable AgBiS 2 nanocrystal (NC) photoanode. It was observed that the characteristics of the ligand used for the AgBiS 2 NC photoanode are crucial in determining its PEC water splitting performance. Moreover, the thiol ligand-capped AgBiS 2 NC photoanode shows a higher photocurrent density ( J ph ) in both 1 sun and visible light than typical TiO 2 or Bi 2 S 3 NC photoanodes owing to its excellent electron collection ability and low interfacial charge transfer resistance. The AgBiS 2 NC photoanode emits 91% of J ph under visible and near-IR light, whereas the Bi 2 S 3 NC photoanodes exhibited a J ph of 67% under the same conditions, demonstrating the superiority of AgBiS 2 NC materials for application in highly efficient visible-light-driven PEC devices.