Redox‐Driven In Situ Formation of Bimetallic Catalysts via Sn 2+ /Sn 4+ Interconversion

Bimetallic catalysts have garnered substantial interest across diverse fields due to their distinctive geometric and electronic structures. Nevertheless, achieving uniformly distributed bimetallic catalysts remains challenging due to the solubility or charge properties of ions in specific bimetallic systems. Herein, we present an innovative in situ redox-driven synthesis strategy utilizing Sn²⁺/Sn⁴⁺ interconversion to address these challenges. By immobilizing Sn²⁺ ions on Al-deficient alumina and capturing secondary metal ions through redox reactions, we successfully synthesized eight distinct Sn-M bimetallic catalysts. The representative Sn-Pt catalysts derived from [PtCl₄]^2- or [Pt(NH₃)₄]²⁺ ions, lead to the reduction of Pt²⁺ to Pt⁰ with analogous local structures, resulting in comparable catalytic performance in carbon monoxide oxidation and propane dehydrogenation. This redox-driven synthesis strategy can be extended to other bimetallic systems, with promising preliminary results observed in Cr-M systems. This innovative strategy effectively mitigates the hydrolysis of tin ions, neutralizes the influence of ion charges, and addresses the solubility challenges of secondary metal ions, providing a robust solution for the design of bimetallic catalysts.