Facet‐Selective Deposition of Metal (M=Au, Pt, Pd) Nanoparticles on Co3O4 Crystals: Magnetically Separable Photocatalyst with Improved Catalytic Performance

: Depositing noble metals on specific facets of semiconductors can improve the separation of photoexcited hole-electron pairs during the photocatalytic reaction, resulting in enhanced photocatalytic performance. This work describes the selective deposition of noble metal nanoparticles (Au, Pt, Pd) on some specific facets of p-type Co3 O4 through a simple and facile photoassisted method. The deposition of Au nanoparticles (NPs) on {111} facets of Co3 O4 nanocrystals (NCs) can remarkably improve their photocatalytic activity towards water oxidation, which can be attributed to enhanced charge spatial separation. Moreover, the magnetically separated photocatalysts are good examples of new designed photocatalysts that can be recovered easily.