In photoelectrochemical water splitting (PEC), semiconductors absorb sunlight and generate electron-hole pairs that drive redox reactions at electrode/electrolyte interfaces. Photoexcited charge carriers must be separated and transported effectively to avoid recombination, which is crucial to improving hydrogen production efficiency. Our research is dedicated to developing advanced energy materials with functionality to enhance charge transfer efficiency and optimize sunlight absorption, improving water-splitting performance. In our investigation, we employ ultrafast time-resolved X-ray absorption spectroscopy (XAS operation), an advanced analytical technique that can be used to study charge carrier dynamics live during PEC operation. By observing and analyzing electron and hole behavior following light absorption, XAS provides valuable insights into their spatial distribution, transport mechanisms, and recombination processes.

These insights are pivotal in guiding the development of innovative materials, interfaces, and catalysts aimed at significantly enhancing the efficiency and durability of PEC devices. Ultimately, our goal is to advance the scientific understanding and technological capabilities of PEC water splitting, thereby contributing to sustainable energy solutions. By harnessing solar power for efficient hydrogen fuel production, our research aims to reduce dependence on fossil fuels and mitigate environmental impacts associated with conventional energy sources .