Dispersed Nickel Cobalt Oxyphosphide Nanoparticles Confined in Multichannel Hollow Carbon Fibers for Photocatalytic CO2 Reduction.

Abstract

Advanced materials for high-efficiency photocatalytic CO2 reduction are desirable for solar-to-carbon fuel conversion. Herein, highly dispersed nickel cobalt oxyphosphide nanoparticles (NiCoOP NPs) have been confined in multichannel hollow carbon fibers (MHCFs) to construct the NiCoOP NPs@MHCFs catalysts for efficient CO2 photoreduction. The synthetic strategy involves a multistep process (i.e., electrospinning, phosphidation and carbonization) and permits facile tuning of chemical composition. In the NiCoOP NPs@MHCFs catalyst, the mixed metal oxyphosphide NPs with ultrasmall size and high dispersion offer abundant catalytically active sites for redox reactions. At the same time, the multichannel hollow carbon matrix with high conductivity and open ends will effectively promote mass/charge transfer, improve CO2 adsorption and prevent the metal oxyphosphide NPs from aggregation. Benefiting from the distinct structural and compositional merits, the optimized hetero-metal oxyphosphide catalyst exhibits considerable activity for photosensitized CO2 reduction, affording a high CO evolution rate of 16.6 µmol h-1 (per 0.1 mg of catalyst).