Synthesis and photocatalytic activity of ultrathin two-dimensional porphyrin nanodisks via covalent organic framework exfoliation

Two dimensional polymers have emerged in recent years as useful materials for the development of catalysts for future energy demand. However, the synthesis of ultrathin organic two dimensional polymers is still limited and further development is necessary. Here we present the synthesis of nanometer-thick two-dimensional (2D) porphyrin polymer nanodisks via the exfoliation of covalent organic frameworks, and evaluate their performance in the hydrogen evolution reaction under irradiation with broadband light. The nanodisks are synthesized through the simultaneous axial coordination of pyridines and metal ions to produce 2D porphyrin nanodisks of 1 nm average thickness. Importantly, the polymer composite with platinum-reduced graphene oxide exhibits hydrogen evolution activity upon irradiation with visible and NIR light. These results represent the use of 2D ultrathin polymer nanodisks derived from covalent organic frameworks in heterogeneous photocatalytic processes.