Ultrafast Photothermal Conversion of Ru/Zn Heterometallic Metal-Organic Framework for Synergistic Catalytic CO₂...

Solar-driven photothermal catalytic conversion of CO₂ into high-value chemicals offers a promising strategy to enhance solar energy utilization and mitigate the energy crisis. However, the development of catalytic materials that simultaneously exhibit strong light absorption, rapid photothermal conversion, and excellent stability remains a significant challenge. Herein, we report a metal-organic framework, GIA-RuZn, which integrates light-harvesting [Ru(bpy)₃]²⁺ units and catalytically active Zn²⁺ centers into a highly stable interwoven architecture. GIA-RuZn shows remarkable light absorption and ultrafast photothermal conversion, reaching 155.7 °C within only 1.3 s under 808 nm laser irradiation (0.8 W cm^-2). Under 20 W white LED irradiation, GIA-RuZn efficiently catalyzes the carboxylative cyclization of propargylic amines with CO₂. It achieves a 99% yield and an outstanding turnover number (TON) of 556, surpassing most reported catalysts for this reaction. The framework demonstrates excellent stability, retaining structural integrity in both 2  M NaOH and 1 M HCl aqueous solutions and maintaining high performance over 10 recycling tests. Mechanistic studies through DFT calculations confirm that GIA-RuZn significantly decreases the reaction energy barrier, particularly during cyclization, reducing ΔG^‡ from 29.1 to 18.1 kcal/mol. This molecular-level design strategy for multifunctional photothermal catalysts within a stable framework establishes a highly efficient and sustainable platform for advanced CO₂ conversion.