Efficient CO2-to-CO conversion in dye-sensitized photocatalytic systems enabled by electrostatically-driven catalyst binding†

The development of noble metal-free dye-sensitized photocatalytic systems (DSPs) for CO₂-to-CO conversion remains limited. Current literature primarily focuses on a single strategy: the simultaneous loading of both the photosensitizer (PS) and the catalyst (CAT) onto titanium dioxide nanoparticles (TiO₂ NPs) using anchoring groups. Here, we introduce an innovative method through immobilizing a positively-charged molecular CAT onto negatively-charged PS–TiO₂ NPs. Our approach yields promising results, including near-complete CO₂-to-CO conversion (∼100% CO) and exceptional stability, achieving 1658 turnover numbers versus the CAT and an apparent quantum yield efficiency (AQY) of 16.9%.