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

Materials for high-efficiency photocatalytic CO₂ reduction are desirable for solar-to-carbon fuel conversion. Herein, highly dispersed nickel cobalt oxyphosphide nanoparticles (NiCoOP NPs) were confined in multichannel hollow carbon fibers (MHCFs) to construct the NiCoOP-NPs@MHCFs catalysts for efficient CO₂ photoreduction. The synthesis involves electrospinning, phosphidation, and carbonization steps and permits facile tuning of chemical composition. In the 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. 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). © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim