Photocatalytic oxidation of benzyl alcohol coupled with p-dinitrobenzene reduction over poly(o-phenylenediamine) nanowires-decorated Gd-TiO2 nanorods

Simultaneous oxidation of benzyl alcohol (BA) and reduction of p-dinitrobenzene (p-DNB) over Gd-doped TiO 2   nanorods decorated with poly(o-phenylenediamine, PoPD) nanowires was reported in this work. The doping of TiO 2 with Gd induced surface defects, i.e., oxygen vacancy (OV) and the Ti 3+ –on-Ti 4+   site, while incorporating PoPD highly enhanced the light absorption capability and electron conductivity of TiO 2   nanorods ,   as confirmed by UV–vis diffuse reflectance spectroscopy (DRS) and electrochemical measurements, respectively. BA was selectively oxidized by photogenerated h +   to form benzaldehyde with a yield of 70.5% in water and 90.6% in acetonitrile solvent. Conversely, p-DNB was selectively reduced to p-nitroaniline (p-NA) with a yield of 89.1% in acetonitrile and to p-phenylenediamine (p-PDA) of 85.0% yield in water. This work demonstrates a vital strategy to utilize the full economic potential of photogenerated charge carriers and the decisive role of solvent for product selectivity in the course of selective organic transformations.