The conversion of CO2 under mild condition is of great importance because these reactions involving CO2 can not only produce value-added chemicals from abundant and inexpensive CO2 feedstock but also close the carbon cycle.However,the chemical inertness of CO2 requires the development of high-performance catalysts.Herein,Ag nanoparticles/MIL-100(Fe) composites were synthesized by simple impregnation-reduction method and employed as catalysts for the photothermal carboxylation of terminal alkynes with CO2.MIL-100(Fe) could stabilize Ag nanoparticles and prevent them from aggregation during catalytic process.Taking the advantages of photothermal effects and catalytic activities of both Ag nanoparticles and MIL-100(Fe),various aromatic alkynes could be converted to corresponding carboxylic acid products (86％-92％ yields) with 1 atm CO2 at room temperature under visible light irradiation when using Ag nanoparticles/MIL-100(Fe) as photothermal catalysts.The catalysts also showed good recyclability with almost no loss of catalytic activity for three consecutive runs.More importantly,the catalytic performance of Ag nanoparticles/MIL-100(Fe) under visible light irradiation at room temperature was comparable to that upon heating,showing that the light source could replace conventional heating method to drive the reaction.This work provided a promising strategy of utilizing solar energy for achieving efficient CO2 conversion to value-added chemicals under mild condition.