Spinel　CuCo2O4　nanoplates　were　synthesized　through　a　solvothermal　method　coupled　with　a　calcination　treatment　in　air.　The　prepared　CuCo2O4　samples　were　fully　characterized　by　diverse　physical　and　chemical　techniques　including　powder　X-ray　diffraction　(XRD),　field　emission　scanning　electron　microscope　(SEM),　transmission　electron　microscope　(TEM),　X-ray　photoelectron　spectroscopy　(XPS)　and　N-2　sorption　measurement.　The　CuCo2O4　material　was　developed　as　an　efficient,　low-cost　and　stable　cocatalyst　to　boost　photochemical　CO2　conversion　with　Ru(bpy)(3)(2+)　as　a　homogeneous　photosensetizer.　The　catalytic　performance　of　the　CuCo2O4　samples　was　evaluated　toward　visible-light-driven　deoxygenative　reduction　of　CO2　to　CO　under　mild　conditions.　Various　parameters　of　the　reaction　system　and　the　synthesis　conditions　of　CuCo2O4　were　investigated　and　optimized　to　maximize　the　catalytic　performance　of　CO2　reduction　system.　The　stability　and　the　reusability　of　the　CuCo2O4　cocatalyst　were　examined.　Moreover,　the　CuCo2O4　cocatalyst　was　further　proved　to　be　highly　active　to　promote　CO2　photoreduction　catalysed　by　CdS　semiconductor　as　a　heterogeneous　light　harvester,　and　markedly　reinforced　photocatalytic　CO2　reduction　performance　was　achieved.　(C)　2016　Elsevier　B.V.　All　rights　reserved.