Facile approach to defect-rich ZnO photocatalysts for visible light dye degradation

We established an effective synthesis approach to prepare
planar-defect-rich-zinc oxide (ZnO) nanoparticles via a facile
coprecipitation technique. The effect of acetate, sulfate, and nitrate
salt precursors along with synthesis temperature on the physiochemical
behavior of ZnO nanoparticles was explored. Various analytical techniques
were utilized to illustrate the present phases, intrinsic structure,
extrinsic morphology, and optical properties of the final products. Pure
hexagonal wurtzite phase for the ZnO nanoparticles with spherical
morphology ranging from 30 nm to 70 nm in size displayed superior
photocatalytic activity owing to the presence of a high density of
dislocation and stacking faults. A visible-light photocatalytic
degradation study of methylene blue and rhodamine B dye was carried out.
Prepared ZnO nanoparticles were able to degrade over 93% of 22 MB dye and
98.85% RhB dye in an hour. This excellent visible-light photocatalytic
activity is credited to the porous nature of the nanoparticles offering
increased surface area and the presence of planar defects which
effectively repress electron-hole recombination by taking care of charge
carrier trapping and transferring.