Feasible Synthesis of C Fibers@C-MoO2+x Submicro-particles Core-shell Composite for Highly Efficient Solar-driven Photocatalyst

Molybdenum dioxide (MoO2) is attractive due to its applications in optical, electrical, and new energy fields. However, due to the poor conductivity, pure MoO2 possesses inferior photocatalytic activity because of the strong recombination between photogenerated electrons and holes. One of the methods to overcome this shortage is to enable nanostructured MoO2 to be composited with highly conductive materials like carbon fibers. Herein, we fabricate an interesting C fibers@C-MoO2+x nanoparticle core-shell composite by heat treating Polyacrylonitrile (PAN) fibers covered with PAN and MoO3 powder in Ar gas, in which the PAN carbonize into conductive carbon in a heating process and meanwhile, the emitting reducing gases in-situ transform MoO3 to conducting MoO2+x submicron-particles. Under simulated sunlight irradiation, the photocatalytic removal rate for rhodamine B, phenol, and K2Cr2O7 on such composite are 11.28, 5.15, and 6.19 times those on commercial MoO2 powder, respectively. The prepared composite presents excellent photocatalytic performance and outstanding stability for degrading various environmental pollutants in water, which will be a good solar-driven photocatalyst candidate for the degradation of toxic chemicals in industrial wastewater for environmental remediation. Furthermore, this simple preparation strategy represents an easily operated, low-cost, and environmentally friendly solution for industrial production.