Organic Photovoltaic Catalyst with Extended Exciton Diffusion for High-Performance Solar Hydrogen Evolution
Yufan Zhu, Zhenzhen Zhang, Wenqin Si, Qianlu Sun, Guilong Cai, Yawen Li, Yixiao Jia, Xinhui Lu, Weigao Xu, Shiming Zhang, Yuze Lin
Abstract
The short exciton diffusion length (LD) associated with most classical organic photocatalysts (5–10 nm) imposes severe limits on photocatalytic hydrogen evolution efficiency. Here, a photovoltaic molecule (F1) without electron-deficient units at the central building block was designed and synthesized to improve the photoluminescence quantum yield (PLQY). With the enhanced PLQY of 9.3% and a large integral spectral overlap of 3.32 × 1016 nm4 M–1 cm–1, the average LD of F1 film increases to 20 nm, nearly twice the length of the control photovoltaic molecule (Y6). Then, the single-component organic nanoparticles (SC-NPs) based on F1 show an optimized average hydrogen evolution rate (HER) of 152.60 mmol h–1 g–1 under AM 1.5G sunlight (100 mW cm–2) illumination for 10 h, which is among the best results for photocatalytic hydrogen evolution.