Organic semiconductors hold promise to enable scalable, low-cost and high-performance artificial photosynthesis. However, the performance of systems based on organic semiconductors for light-driven water oxidation have remained poor compared with inorganic semiconductors. Herein, we demonstrate an all-polymer bulk heterojunction organic semiconductor photoanode for solar water oxidation. By engineering the photoanode interlayers we gain important insights into critical factors (surface roughness and charge extraction efficiency) to increase the operational stability, which reaches above 3 h with a 1-Sun photocurrent density, J_ph, of >3 mA cm⁻² at 1.23 V versus the reversible hydrogen electrode for the sacrificial oxidation of Na₂SO₃ at pH 9. Optimizing the coupling to an oxygen evolution catalyst yields O₂ production with J_ph > 2 mA cm⁻² at 1.23 V versus the reversible hydrogen electrode (100% Faradaic efficiency and a quantum efficiency up to 27% with 610 nm illumination), demonstrating improved stability (≥1 mA cm⁻² for over 30 min of continuous operation) compared with previous organic photoanodes.

有机半导体有望实现可扩展、低成本和高性能的人工光合作用。然而，与无机半导体相比，基于有机半导体的光驱动水氧化系统的性能仍然很差。在此，我们展示了一种用于太阳能水氧化的全聚合物本体异质结有机半导体光阳极。通过设计光阳极中间层，我们获得了对关键因素（表面粗糙度和电荷提取效率）的重要见解，以提高操作稳定性，在 1-Sun 光电流密度J _ph大于 3 mA cm ^-2时达到 3 小时以上1.23 V 与可逆氢电极相比，用于 Na ₂ SO ₃的牺牲氧化在 pH 9 时。优化与析氧催化剂的耦合产生 O ₂生产，在 1.23 V 时J _ph  > 2 mA cm ^-2与可逆氢电极相比（100% 法拉第效率和高达 27% 的量子效率，610 nm 照明)，与以前的有机光阳极相比，稳定性提高了（≥1 mA cm ^-2连续运行超过 30 分钟）。