An ultrathin porphyrin-based metal-organic framework for efficient photocatalytic hydrogen evolution under visible light.

Development of inorganic semiconductor photocatalysts for efficient photocatalytic production of clean and renewable hydrogen has long been attracting tremendous attentions. Herein, we report an ultrathin porphyrin-based metal-organic framework (PMOF) with Ti-oxo clusters, exhibiting a photocatalytic hydrogen evolution rate of as high as 8.52 mmol⋅g⁻¹⋅h⁻¹ in the presence of Pt as cocatalyst under a wide range of visible light irradiation up to 700 nm. The photocatalytic reaction over PMOF is a typical ligand-to-metal charge transfer (LMCT) process, i.e., the photoinduced electrons transfer from porphyrin-based ligands (light harvester) to Ti-oxo clusters (catalytic center), and thereby the charge carriers' separation is significantly enhanced. Moreover, the long-term course reaction confirms the excellent water-resistance and photo-stability of PMOF in photocatalytic hydrogen evolution. An ultrathin porphyrin-based metal-organic framework (PMOF) with Ti-oxo clusters exhibits efficient photocatalytic hydrogen evolution under a wide range of visible-light irradiation. Image 1 • Ultrathin porphyrin-based MOF (PMOF) shows high water-resistance and photostability. • Efficient photocatalytic H 2 evolution over PMOF under wide range visible light. • Porphyrin-based ligands harvest light; Ti-oxo clusters act as catalytic center. • The ligand-to-metal charge transfer plays a role in photocatalytic H 2 evolution. [ABSTRACT FROM AUTHOR]