Dumbbell-Shaped Au@CeO₂ Metal–Semiconductor Heteronanocrystals for Photothermal Catalysis of Organophosphate Degradation

Plasmonic metal and semiconductor heterostructures have recently emerged as a promising strategy to enhance the rate of catalyzed reactions. However, most research has predominantly focused on plasmon-induced hot electron transfer mediated by localized surface plasmon resonance (LSPR), while the photothermal effects of plasmonic metals have been largely underexplored. In this study, a dumbbell-shaped Au nanobipyramids (AuNBPs)/CeO₂ heterojunction with superior photothermal properties was designed as a catalytic platform for the hydrolysis of organophosphorus compounds and the reduction of 4-nitrophenol (p-NP). The results demonstrated that the photothermal effect at the interface between AuNBPs and CeO₂ is the dominant mechanism accelerating the reaction. Moreover, for the hydrolysis product p-NP, AuNBPs@CeO₂ further converted it into 4-aminophenol (p-AP) in the presence of NaBH₄, effectively preventing secondary pollution. In summary, the integration of AuNBPs with photothermal properties and CeO₂ successfully achieved cascade catalytic degradation of organophosphates.