In this work, electrospun nanofiber embedded with zinc
oxysulfide
(Zn(O,S)) has been demonstrated as an efficient and robust photocatalyst
for hydrogenation of nitrobenzene to aniline under solar light irradiation
at mild conditions with methanol as the hole scavenger. The solid
solution state of Zn(O,S) in electrospun nanofiber was successfully
revealed by high-resolution transmission electron microscopy and X-ray
diffraction analyses in which the lattice fringes and diffraction
planes located in between those of ZnO and ZnS phases. Moreover, the
electrochemical and optical properties of Zn(O,S) embedded in polyethylene
oxide (PEO) nanofiber are found to be better than those of ZnO and
ZnS indicating more efficient photocatalytic activities as well. The
photocatalytic hydrogenation of nitrobenzene to aniline occurred completely
within 2 h of the photocatalytic reaction with a reusability of 95%
after five consecutive runs. Finally, the mechanism of photocatalytic
hydrogenation by Zn(O,S) embedded in the PEO (PZOS) nanofiber involves
a total of six electrons (e–) and six protons (H+) to hydrogenate nitrobenzene to nitrosobenzene, phenylhydroxylamine,
and aniline.