Phosphorization-derived MoP@MoO_3-x nanowires for selective photocatalytic oxidation of benzyl alcohol to benzaldehyde

The selective oxidation of small molecules to high-value-added products is regarded as a promising approach to alleviating the worldwide energy crisis. In this work, heterogenous non-noble-metal molybdenum(III) phosphide (MoP) catalysts were anchored onto MoO_3−x nanowires (MoP@MoO_3−x) via a facile phosphorization method using various amounts of phosphorus precursor. Because of the combined attributes of the MoP and the MoO_3−x nanowires, the novel MoP@MoO_3−x nanowire catalysts not only provide more active sites but also enhance electron–hole separation efficiency. The results show that the selective transformation of benzyl alcohol to benzaldehyde was achieved with 67% selectivity. A comprehensive study including field-emission transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, Brunauer–Emmett–Teller analysis, X-ray diffraction analysis, UV–vis diffuse reflectance spectrum, electron-spin resonance, photocurrent measurements, electrochemical impedance spectroscopy, and density functional theory (DFT) computations was conducted. The selective photocatalytic oxidation results and the DFT calculations indicate that the MoP particles anchored onto the MoO_3−x substrate display an important role in enhancing the selective photocatalytic oxidation of benzyl alcohol.