A review on conversion of carbon dioxide ( CO 2 ) to methanol and methane by photocatalytic reactors: a comparative analysis with algae‐based CO 2 sequestration

Abstract Carbon dioxide (CO 2 ) emission due to urbanization and industrialization are the key factors behind global warming and climate changes. United Nations in 2018, stated that, due to CO 2 emissions, earth's temperature would increase 1.5 °C between 2032 and 2050. Variation in climatic conditions will definitely have a huge impact on human health and ecosystem. To mimic the CO 2 emission, various countries have put forward laws and policies. This review focuses primarily on the biological and photocatalytic reduction of CO 2 to valuable products like chemicals and fuels. This review provides valuable information on the reduction of CO 2 to valuable products and benefits the researchers, academics, and industrial personnel on resource recovery concepts. Photo reactor design and operating conditions define the level of CO 2 conversion efficiency. Algae‐based CO 2 utilization and recovery of products from algae biomass are explored for biofuel production process. However, the storage capacity of products, bulk processing of CO 2 are needed in future research perspectives. Overall, this study strongly contributes towards achieving sustainable development goals (SDGs). © 2025 Society of Chemical Industry (SCI).