Hollow Co3O4/CdS Nanoparticles for Photocatalytic Hydrogen Evolution and Photodegradation

Ultrathin hollow core–shell nano pn junction of Co3O4/CdS is fabricated by chemical-calcination method. The Co3O4/CdS nano pn junction (Co/Cd-3) exhibits prominently enhanced photocatalytic hydrogen evolution (∼6250.47 μmol·g–1·h–1) and photodegradation compared to those of Co3O4 (∼90-fold/∼35-fold) and CdS (∼60-fold/∼30-fold). Co3O4/CdS nano pn junction with greater potential gradient and Co3O4 with higher absorption can ameliorate the carrier efficiency, including transportation increasing, lifetime prolonging, and recombination decreasing. In addition, formed ultrathin hollow nanostructure can increase photocatalytic active sites and light reflections and shorten carrier pathway, while still maintaining good stability.