Fig. 5. Photocatalytic CO₂ reduction.

Experiments were performed in CO₂-saturated DMF solution containing a 0.1 mM CuPP (red) or 0.2 mM PP (black), and 100 mM BIH; b 0.2 mM PP (black) or 0.1 mM CuPP (red), 0.2 µM FeTDHPP, and 10 mM BIH; c 0.1 mM CuPP, 0.2 μM FeTDHPP, and 100 mM BIH. Error bar (95% confidence interval based on three runs) is included at the 1-h point, which is the typical error in the measurement (14%). Source data are provided as a Source Data file.