High-performance and stable photoelectrochemical water splitting cell with organic-photoactive-layer-based photoanode
Je Min Yu, Jung‐Ho Lee, Yoon Seo Kim, Jaejung Song, Jiyeon Oh, Sang Myeon Lee, Mingyu Jeong, Yongseon Kim, Ja Hun Kwak, Seungho Cho, Changduk Yang, Ji‐Wook Jang
Abstract
Abstract Considering their superior charge-transfer characteristics, easy tenability of energy levels, and low production cost, organic semiconductors are ideal for photoelectrochemical (PEC) hydrogen production. However, organic-semiconductor-based photoelectrodes have not been extensively explored for PEC water-splitting because of their low stability in water. Herein, we report high-performance and stable organic-semiconductors photoanodes consisting of p -type polymers and n -type non-fullerene materials, which is passivated using nickel foils, GaIn eutectic, and layered double hydroxides as model materials. We achieve a photocurrent density of 15.1 mA cm −2 at 1.23 V vs. reversible hydrogen electrode (RHE) with an onset potential of 0.55 V vs. RHE and a record high half-cell solar-to-hydrogen conversion efficiency of 4.33% under AM 1.5 G solar simulated light. After conducting the stability test at 1.3 V vs. RHE for 10 h, 90% of the initial photocurrent density are retained, whereas the photoactive layer without passivation lost its activity within a few minutes.