Carbon dioxide (CO₂) is a main component part of greenhouse gases. Since catalytic reduction of CO₂ to hydrocarbon fuels can realize the recyclable utilization of carbon materials, this topic has been intensively looked into. In this article, the recent progress on the conversion of CO₂ has been reviewed and discussed in detail by comparing and analyzing the catalytic efficiency and catalytic selectivity of different methods, three of which, photocatalytic reduction, electrocatalytic reduction, and photoelectrocatalytic reduction are covered. The respective catalysis mechanisms of each method,as well as the effects of different catalysts and catalytic systems on reduction of CO₂ have been described. According to previous studies in this area, catalytic performance, photo-electric converting,catalytic selectivity, and energy consumption are the primary criteria on evaluating the method of reduction of CO₂. On this basis, the advantages and disadvantages of catalysts and methods for reducing CO₂ to useable energy are summarized and analyzed. In the last part of the article, prospects and challenges for the further development in this field are presented. Contents 1 Introduction
2 Photocatalytic reduction of CO₂
2.1 TiO₂-based photo-catalytic system
2.2 Ternary metal oxide photo-catalytic system
2.3 Metal complex photo-catalytic system
3 Electrocatalytic reduction of CO₂
3.1 Metal electro-catalytic system
3.2 Metal complex electro-catalytic system
3.3 Ionic liquid electrochemical reaction system
4 Photoelectrocatalytic reduction of CO₂
5 Outlook