Designed Architecture of Porous Organic Polymer Wrapped MnFe2O4 Nanocrystals: A Novel Water Splitting Photocatalyst

A novel MnFe2O4–porous organic polymer (POP) nanocomposite was synthesized by a facile hydrothermal method and using the highly cross-linked N-rich benzene–benzylamine POP. The nanocomposite presented highly efficient photocatalytic performance in the hydrogen evolution reaction (HER) from pure water without addition of any sacrificial agent under one AM 1.5 G sunlight illumination. A photocatalytic activity of 6.12 mmol h−1 g−1 was achieved in the absence of any noble metal cocatalyst, which is the highest H2 production rate reported for nonprecious metal catalysts. The photocatalytic performance of MnFe2O4-POP could be attributed to the intrinsic synergistic effects of manganese ferrite (MnFe2O4) nanoclusters interacting with the nitrogen dopant POP with a unique mesoporous nanoarchitecture and spatially confined growth of MnFe2O4 in the interconnected POP network, leading to high visible-light absorption with fast electron transport.