Self-Healing of Molecular Catalyst and Photosensitizer on Metal–Organic Framework: Robust Molecular System for Photocatalytic H2 Evolution from Water

• Published in: Journal of the American Chemical Society Vol. 138; no. 28; pp. 8698 - 8701
• Main Authors: Kim, Dongha, Whang, Dong Ryeol, Park, Soo Young
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 20.07.2016
• Subjects: Catalysis; catalysts; hydrogen; Hydrogen - chemistry; hydrogen production; Imines - chemistry; Metal-Organic Frameworks - chemistry; Models, Molecular; Molecular Conformation; photocatalysis; photosensitizing agents; Photosensitizing Agents - chemistry; photosystem II; Water - chemistry
• ISSN: 0002-7863; 1520-5126; 1520-5126
• DOI: 10.1021/jacs.6b04552

Inspired by self-repair mechanism of PSII in plants, we report a self-healing system which spontaneously repairs molecular catalyst and photosensitizer during photocatalytic H2 evolution. A bipyridine-embedded UiO-type metal–organic framework (MOF), namely Pt n _Ir_BUiO, which incorporated H2-evolving catalyst and photosensitizer, was synthesized and subject to photocatalytic H2 evolution reaction (HER). Impressively, HER with Pt0.1_Ir_BUiO showed very stable molecular photocatalysis without significant decrease in its activity and colloidal formation for 6.5 days at least; in the homogeneous counterpart, the molecular catalyst became a colloid just after 7.5 h. It was revealed that the arrangement of diimine sites which closely and densely surrounded the H2-evolving catalyst and photosensitizer in the MOF enabled such a highly efficient self-healing.