The Effect of Energy Level Alignment in Organic Photocathodes
발표자
김훈 (울산과학기술원)
연구책임자
조한희 (울산과학기술원)
초록
내용
Organic semiconductor bulk heterojunction (OS BHJ)-based photoelectrochemical (PEC) cells offer a promising route for green hydrogen (H2) production on a global scale. While energy level alignment governs charge generation within OS BHJ layers, its impact on the performance and operational stability of OS PEC cells remains poorly understood. Herein, we systematically investigated the effect of energy levels on the overall performance of OS-based photocathodes by employing a widely used non-fullerene acceptor, Y6, and a polymerized small molecule acceptor, PYIT, which have different energy levels despite their chemical similarities. Interestingly, PYIT-based photocathodes exhibited improved stability for solar-driven water reduction in neutral pH conditions due to their favorable energy level alignment for efficient charge transfer whereas Y6-based photocathodes showed inferior stability. This finding highlights the importance of energy level alignment in designing OS-based PEC cells.