The recent discovery that metal‐free polyterthiophene (PTTh) prepared by iodine‐vapor‐assisted polymerization (IVP) can catalyze the hydrogen evolution reaction (HER) when illuminated, and this light‐enhanced electrolysis expresses a non‐Nernstian relation with pH, provides the foundation for further improvement of the photovoltage of the reaction by engineering the band structure of the light‐absorbing polymer. Deviating from an all‐thiophene backbone, using poly(1,4‐di(2‐thienyl))benzene (PDTB) lowers the highest occupied molecular orbital level by ≈0.3 eV compared with polythiophene, and PDTB simultaneously maintains the photoelectrocatalytic properties without an all‐thiophene backbone, resulting in very high conversion rate of 600 mmol(H₂) h⁻¹ g⁻¹ at 0 V versus the reversible hydrogen electrode (RHE) at pH 11. PDTB shows the same non‐Nernstian behavior as PTTh with increasing onset potential (versus RHE) at higher pH, and the open circuit potential on PDTB under visible light reaches 1.4 V versus RHE at pH 12. The PDTB photocathode thus produces a photovoltage above the theoretical potential for the complete water‐splitting (1.229 V) and is indeed able to produce hydrogen in a one‐photon‐per‐electron light‐driven water splitting setup with MnO_x as the anode at a rate of 6.4 mmol h⁻¹ g_PDTB⁻¹.

中文翻译：

---

聚（1,4-二（2-噻吩基））苯有助于在高pH下可见光下完全光驱动的水分解

最近的发现表明，通过碘汽化聚合（IVP）制备的无金属聚对噻吩（PTTh）可以在光照时催化析氢反应（HER），并且这种光增强的电解表现出与pH值的非能斯特关系。通过设计吸光聚合物的能带结构为进一步提高反应的光电压奠定基础。与聚噻吩相比，使用聚（1,4-二（2-噻吩基））苯（PDTB）与全噻吩骨架不同，最高占据分子轨道能级降低约0.3 eV，PDTB同时保持了光电催化性能，而没有聚噻吩。全噻吩骨架，产生非常高的600 mmol（H ₂）h ^-1 g ^-1转化率在0 V下与pH 11下的可逆氢电极（RHE）相比，PDTB在较高pH下显示出与PTTh相同的非能斯行为，且其起始电势增加（相​​对于RHE），可见光下PDTB的开路电势达到1.4 V相对于pH为12的RHE而言，PDTB光电阴极产生的光电压高于完全水分解的理论电位（1.229 V），并且确实能够在单光子/电子光驱动水分解装置中产生氢气以6.4 mmol h ^-1 g _PDTB ^-1的速率作为阳极的MnO _x。