A NIR-Responsive Phytic Acid Nickel Biomimetic Complex Anchored on Carbon Nitride for Highly Efficient Solar Hydrogen Production

A challenge in photocatalysis consists in improving the efficiency by harnessing a large portion of the solar spectrum. We report the design and realization of a robust molecular-semiconductor photocatalytic system (MSPS) consisting of an earth-abundant phytic acid nickel (PA-Ni) biomimetic complex and polymeric carbon nitride (PCN). The MSPS exhibits an outstanding activity at lambda=940 nm with high apparent quantum efficiency (AQE) of 2.8 %, particularly lambda>900 nm, as it outperforms all reported state-of-the-art near-infrared (NIR) hybrid photocatalysts without adding any noble metals. The optimum hydrogen (H-2) production activity was about 52 and 64 times higher with respect to its pristine counterpart under the AM 1.5 G and visible irradiation, respectively, being equivalent to the platinum-assisted PCN. This work sheds light on feasible avenues to prepare highly active, stable, cheap NIR-harvesting photosystems toward sustainable and scalable solar-to-H-2 production.

Automated summary

The study presents a molecular-semiconductor photocatalytic system (MSPS) composed of a phytic acid nickel biomimetic complex and polymeric carbon nitride, which shows outstanding hydrogen production activity under the near-infrared spectrum. The MSPS not only enhances the hydrogen production activity but also reduces the need for noble metals.