Abstract

The increasing concentration of carbon dioxide (CO₂) in the atmosphere, surpassing critical safety thresholds, alongside rising global energy demands driven by population growth, underscores the urgent need for sustainable energy solutions. This review explores various techniques-thermal, photochemical, electrochemical, and enzymatic-aimed at converting CO₂ into valuable hydrocarbons and other products. Enzymatic approaches, utilizing proteins and microorganism-based enzymes for CO₂ reduction via redox reactions, are highlighted for their environmental friendliness, reduced toxicity, and efficiency in transforming CO₂ into hydrocarbon fuels. Strategies integrating enzymatic systems with polymers, transition metals, and semiconductors to enhance CO₂ reduction applications are discussed, emphasizing the critical role of enzyme immobilization. Additionally, the review explores the integration of enzyme systems with photo catalysts in semi-artificial photosynthesis systems resembling natural photosystem. Solar fuel generation through photocatalytic CO₂ conversion emerges as a promising approach, harnessing sunlight to efficiently produce methanol (MeOH), ethanol, and formic acid. While metal-based photocatalysts encounter challenges such as poor dispersion and toxicity, bio-inspired alternatives utilizing redox enzymes offer sustainable solutions. The review concludes by addressing emerging challenges and innovative approaches in enzymatic CO₂ reduction, with a focus on optimizing methanol production through multienzyme systems and membrane-based strategies to advance sustainable energy technologies.

Keywords:Biocatalysis; CO₂ conversion; Methanol; Enzymatic catalysis; Microbial metabolism; Sustainable chemistry