Revealing the Principle of Progressively Enhanced Photocatalytic Reactivity in Dual Single‐Atoms‐Mediated Electronic Interactions Optimization of Cd/Te‐TiO₂

Abstract In this work, a CdTe@TiO₂ single atoms (SAs) catalysts is successfully synthesized, realizing unique portion of nonbonding oxygen‐coordinated configuration of Cd─O─Te dimers coupling. Astonishingly, the 5th CdTe@TiO₂ (0.027 min⁻¹) shows progressively augmenting phenomenon, accompanied with 2.73 times higher than that of fresh CdTe@TiO₂ (0.010 min⁻¹) on the photocatalytic rate constant of gaseous toluene conversion. The incrementally enhanced photocatalytic activity is attributed to atomically dispersed Cd/Te SAs sites generation during the photoreduction process, and further leading to the optimized electron interactions between Cd, Te atoms, and TiO₂ NTs and causing a positive shift in the d‐band center closer to the Fermi level. Density Functional Theory (DFT) calculations reveal that this unique Cd/Te SAs increasing phenomenon can mutually elevate the electronic density around Cd/Te SAs and generate a substantial local electric field at the interface. In essence, the free energy barriers of the benzene intermediates ring‐opening as the rate‐determining step appeared to significantly diminish tendency from 1.10 to 0.96 eV, in line with the ICOHP calculation of Cd/Te─O bonds in TS promoted from −2.43 to −3.49 eV. This work unearths the mechanism for ascendant electronic states of synergies dual‐metal sites, providing a versatile strategy to tailor the SAs catalysts for solar energy conversion.