Mesoporous Silica- and Carbon-Supported Materials for Efficient CO 2 Capture and Catalytic Conversion into Liquid Fuels and Methane

Excessive CO2 levels in the atmosphere demand urgent mitigation strategies, including reducing emissions from stationary sources like power plants through carbon capture and conversion of captured CO2 into sustainable fuels and chemicals using thermochemical, electrochemical, or nonthermal-plasma-assisted methods. Mesoporous materials have gained significant attention for decarbonization, with recent developments enhancing their design and effectiveness for both capture and conversion. While mesoporous silicas, such as SBA-15 and KIT-6, functionalized with amines have yielded adsorption capacities up to 5.39 mmol/g at 75 °C, nitrogen-doped mesoporous carbons and carbon nitrides show superior high-pressure uptake, reaching 15.4 mmol/g at 30 bar and 0 °C. Catalysts based on Ni-, Pd-, Fe-, and Cu-supported mesoporous frameworks have demonstrated CO2 conversions in the range of 50–87%, with methane selectivity approaching 99% under specific optimized laboratory conditions. This review highlights advancements in mesoporous adsorbents such as mesoporous silica- and carbon-supported materials, focusing on their surface properties, selectivity, efficiency, and recyclability in CO2 capture and conversion processes. Mesoporous carbons produced from pyrolysis of plastic wastes are also included in the current review, as they have emerged as promising candidates due to their high CO2 uptake, rapid adsorption kinetics, and ease of regeneration; their performance can vary depending on synthesis and operating conditions. Mechanistic pathways for CO2 capture on the adsorbent’s surface and conversion to olefins, alcohols, and other value-added products are presented. The review includes a summary of key challenges, current trends, and future research directions, emphasizing the need for further innovation to optimize mesoporous materials for CO2 capture and conversion applications.