Аннотация:The reaction of photocatalytic reduction of CO2 with water into CO and CH4 in suspensions of theheterojunction semiconductor SiC/ZnO with copper metal Cu (0.5 wt %) deposited on its surface has beenstudied. The formation of CO and a small amount of CH4 has been established; the methane yield increasesfourfold and the CO yield sharply decreases when MgO is additionally deposited on the semiconductor surface.The maximum methane yield is achieved at a MgO content of 1 wt %; however, with a further increasein the amount of MgO, the CH4 yield decreases. The mechanism of CO2 reduction to CO in a two-electronprocess and to CH4 in an eight-electron process is discussed.