Efficient Photocatalytic H ₂ O ₂ Production in a Quasi‐Homogeneous System Utilizing Conjugated Polymer Nanoparticles

ABSTRACT Conjugated polymers demonstrate potential for photocatalytic hydrogen peroxide (H ₂ O ₂ ) generation; however, their inadequate aqueous dispersibility leads to interfacial mismatch and inconsistent hydrophilicity, thereby hindering the migration of charge carriers and ionic species at the water–photocatalyst interface. In this work, three conjugated polymers TAQ, TPPQ, and TMPQ, exhibiting aggregation‐enhanced H ₂ O ₂ production are designed and synthesized. Subsequently, their quasi‐homogeneous photocatalytic systems are fabricated in aqueous media via the nanoprecipitation method assisted by an amphiphilic surfactant, facilitating effective H ₂ O ₂ generation. Under an atmosphere devoid of sacrificial agents, the quasi‐homogeneous systems of TAQ, TPPQ, and TMPQ exhibit H ₂ O ₂ production rates 27–58 times higher than their powder forms. Notably, TAQ achieves a H ₂ O ₂ production rate of 3915µmol g ⁻¹ h ⁻¹ and an apparent quantum yield of 24.6% at 400 nm, representing some of the highest values reported for single‐junction polymer‐based photocatalysts. These findings underscore the efficacy of quasi‐homogeneous system design in markedly improving photocatalytic performance.