Abstract
The production of hydrogen through visible-light-driven water splitting, inspired by natural photosynthesis, is one of the most efficient and environmentally sustainable methods for converting abundant solar energy into a high-energy-density fuel. Organic polymers, with well-tuned energy gaps for efficient electron-hole separation, present a potentially cost-effective and eco-friendly alternative to metal-based photocatalysts. However, the inherently hydrophobic nature of these polymers often hinders their hydrogen evolution efficiency by limiting their solubility or dispersion in aqueous media. To overcome these challenges, recent research has focused on designing hydrophilic polymer photocatalysts capable of addressing these limitations. This brief review highlights the critical need for hydrophilic polymer catalysts and discusses the breakthroughs in their design strategies over the preceding years, for the purpose of visible-light-driven photocatalytic hydrogen evolution.