The　reduction　of　CO2　by　photocatalysis　has　been　widely　considered,　but　the　rapid　recombination　of　photogenerated　carriers　on　photocatalysts　has　become　a　major　constraint　on　efficiency.　Herein,　we　prepare　SiC　nanosheets　with　2H　and　3C　phase　junctions　by　an　in　situ　high-pressure　solvothermal　method.　The　prepared　2H-3C　SiC　nanosheets　promote　charge　carrier　separation　and　the　photocatalytic　reduction　efficiency　of　CO2　to　CO　is　greatly　improved　without　using　a　sacrificial　agent.　The　CO　production　rate　of　this　photocatalyst　reached　6.29　mu　mol　g(-1)　h(-1),　which　is　about　2.4　times　that　of　pure　3C-SiC.　This　work　deepens　the　understanding　of　the　influence　of　the　heterophase　on　photocatalytic　activity　and　provides　a　novel　idea　for　the　application　of　SiC　in　catalysis.