Facet-engineering palladium nanocrystals for remarkable photocatalytic dechlorination of polychlorinated biphenyls

Rationally constructing functionalized cocatalysts for removing chemically inert polychlorinated biphenyls is significant and challenging. In this study, we have synthesized uniform Pd nanocrystals (Pd NCs) with cube (CUB) and octahedron (OCT) geometries, corresponding to the exposed (100) and (111) facets, and they were incorporated with ultrathin TiO2(B) nanosheets (TBs) for the photocatalytic dechlorination of polychlorinated biphenyls under visible light illumination (lambda >= 400 nm). Photocatalytic performance experiments revealed that CUB/TBs is more efficient with a 200% enhancement higher than OCT/TBs. Physicochemical characterizations reveal that the CUB possesses higher surface charge density than OCT, which promotes the activation of the C-Cl bond of polychlorinated biphenyls, leading to higher dechlorination performances of CUB/TBs than OCT/TBs. This study not only fundamentally elucidates the effect of facet-engineering palladium nanocrystals on the photocatalytic dechlorination of polychlorinated biphenyls, but also paves the way for rationally fabricating superior photocatalysts for other advanced applications.

Automated summary

In this study, uniform Pd nanocrystals with cube and octahedron geometries were synthesized and combined with ultrathin TiO2(B) nanosheets for the photocatalytic dechlorination of polychlorinated biphenyls. The CUB/TBs showed a 200% enhancement in efficiency compared to OCT/TBs, attributed to the higher surface charge density of CUB promoting the activation of C-Cl bonds. This research not only elucidates the effect of facet-engineering Pd nanocrystals on the photocatalytic dechlorination of polychlorinated biphenyls but also lays the foundation for superior photocatalysts for other advanced applications.