On the off chance that methods which reduce the global CO ₂ content are unavailable and inefficient, the increasing CO ₂ levels will lead to a synchronized rise in temperature across the world. The conversion of this abundant CO ₂ into hydrocarbons like CH ₄, CH ₃OH, CO, HCOOH and hydrogen fuel using different techniques and their use for power could assist with the world’s energy deficiency and solve the CO ₂ reduction-energy nexus. In this study, photocatalytic CO ₂ conversion by sunlight will be of primary focus since this bears a resemblance with the regular photosynthesis phenomenon. This work also portrays the writings that have narrated the development of mixtures of two or more carbon ions (C ²⁺) within the photocatalytic reduction of CO ₂. This paper thus comprises the energy required for CO ₂ photoreduction, the kinetics mechanisms and thermodynamics requirements. The reaction of CO with water and the hydrogenation of CO ₂ are covered to understand the gap of Gibb’s free energy between both of the reactions. Likewise, the summary of different metal-based co-catalysts, metal-free co-catalysts and their selectivity towards CO ₂ reduction by photocatalysis and reduction of CO ₂ into various hydrocarbons, fuel and materials have also been examined.