Highly Enhanced Photothermal Abatement of Benzene on CeMn x O y –{001}TiO ₂ Nanocomposites Derived from the Asymmetric Interface Structure of Ce and Mn Dual-Site Oxides

Bimetallic oxide composites with heterogeneous interfaces can generate asymmetric structures through the coordination of different metal cations with oxygen ions or vacancies. An asymmetric interface structure was constructed on CeMnxOy-{001}TiO₂ nanocomposites by loading Ce and Mn dual-site oxides on anatase {001}TiO₂. Compared to single Ce or Mn oxide on {001}TiO₂, all Ce and Mn dual-site oxide composites exhibited significantly enhanced photothermocatalytic activity, which was attributed to the asymmetric structure facilitating the release and regeneration of interfacial lattice oxygen. Notably, the photothermocatalytic performance of CMT-B was 3.72 and 2.34 times higher than that of CT and MT, surpassing even that of precious metal catalysts. The strong interfacial interactions within the CeMnxOy-{001}TiO₂ nanocomposites, characterized by the presence of -Ce-O-Mn-, -Ce-O-Ti-, and -Mn-O-Ti- bonding configurations, were confirmed by the observed shifts in the binding energies of Ce⁴⁺ and Ti⁴⁺. Moreover, the photothermocatalytic activity of these nanocomposites increased further with the rising reaction temperature. Importantly, photothermocatalysis is not merely a combination of photocatalysis and thermocatalysis. The promotion of photothermal synergy by -Ce-O-Mn- is further supported by in situ FTIR analysis of CMT-B. This study provides a promising strategy for enhancing the photothermocatalytic degradation of VOCs through the integration of bimetal oxides with photocatalysts.