Diatom-Inspired Design: A New Ru-Based Photosystem for Efficient Oxygen Evolution

The development of efficient and recyclable catalysts is a central pursuit in modern chemistry. Homogeneous catalysts, while effective, often suffer from challenges in separation and recovery, driving the exploration of heterogeneous systems. In this context, this study introduces a novel composite photocatalyst, Ru(bpy)₂(bda)-Ru(bda)(cp)₂@DE (PS/Cat@DE), synthesized by attaching a catalyst (Cat) and a photosensitizer (PS) to diatomaceous earth (DE). The hypothesis that covalently binding the photosensitizer and photocatalyst to the surface of DE could enhance their reactivity and may protect them from degradation was supported by the enhanced photocatalytic performance observed in this study. The composite materials and single components were characterized using UV-Vis and FTIR spectroscopy, as well as SEM, and EDS microscopy. Photocatalytic experiments demonstrated the significantly higher activity of the PS/Cat@DE material compared to equivalent concentrations of the single photosensitizer or photocatalyst components, indicating the crucial role of DE in promoting oxygen evolution.