Solar-driven dry reforming of methane using RuNi single-atom alloy catalyst coupled with thermal decomposition of carbonates

•We synthesized RuNi single-atom alloy catalysts by thermal reduction of single Ru atoms dispersedLDH.•EXAFS analysis demonstrated the successful synthesis of RuNi single-atom alloy.•Under photothermal condition, the RuNi catalyst showed the best performance, achieving high production rates of H2 and CO, respectively.•CO2-emitting thermal decomposition of MgCO3 reaction was coupled with CO2-consuming DRM reaction to convert CO2.