The invention pertains in a first aspect to a plasmonic catalytic process for the reverse water-gas shift (rWGS) reaction using a plasmonic catalyst comprising supported plasmonic metal nanoparticles, and to such a catalyst. An aspect of the invention pertains to a plasmonic catalytic process for the reverse water gas shift reaction (1) CO2 + Hz ~ CO + H2O (1) using a catalyst comprising supported metal nanoparticles, preferably TiO2-supported Au plasmonic nanoparticles, wherein the temperature of the reactor is preferably less than 95°C, the process involving exposing the catalyst to light. Preforably, the catalysL is irradiated with at least solar light or concentrated solar light. Preferably the Au nanoparticles have an average particle size of 5.0 nm or less. The invention also pertains to a catalyst comprising TiO2-supported Au nanoparticles, wherein the Au nanoparticles have an average particle size of 16.0 nm or less, preforably 5.0 nm or less, preforably of 2 nm or loss, o.g. between 1.0 and 2.0 nm, and preferably wherein the catalyst comprises 1- 10 wt.% Au based on weight of TiO2 support, more preferably 2 5 wt.%. Ina preferred emboclimenl, the catalyst cornprises TiO2-supported Au nanoparticles, wherein the nanoparticles preferably have an average particle size 2 nm or less, referably wherein the catalyst comprises 1- 10 wt.% Au based on weight of TiO2 support, more preferably 2 - 5 wt. %, and wherein preferably the support is TiO2 anatase.