Designing dual function materials for integrated carbon dioxide capture and utilisation

Carbon dioxide capture and utilisation (CCU) technologies will play an essential role in decarbonising all sectors to reach a net zero emission future. In particular there is an urgent need to replace fossil derived carbon in the chemical industry as well as in fuels supplied to “hard-to-decarbonise” sectors such as transportation and residential heating. Dual function materials (DFMs) for integrated CCU are materials designed with both adsorbent and catalytic capabilities (hence “dual function”) that can capture and subsequently directly convert dilute streams of CO₂ (from stationary emissions or the atmospheric air) to useful chemicals. In a typical cycle of operation, the DFMs are first exposed to a source of CO₂ to achieve capture, then switched to a stream of co-reactant such as hydrogen or hydrocarbons to achieve the in-situ conversion of captured CO₂. The chemical transformation of captured CO₂ regenerates the adsorbent while releasing a concentrated stream of desired end product. In combining CO₂ capture and utilisation, DFMs can achieve unique synergies that can improve energy efficiency. For example, exothermic hydrogenations of CO₂ such as the methanation reaction can supply heat that then drives CO₂ on adsorbent sites to spill over to catalytic sites during DFM operation. This allows reaction heat to be directly used in the energy intensive process of sorbent regeneration, while maintaining isothermal conditions to promote CO₂ conversion on catalytic sites. This seminar will discuss approaches to develop novel adsorbent materials for CO₂ capture, catalytic materials for the production of sustainable chemicals and present strategies to effectively combine these approaches to yield an integrated CCU system. A rational design approach based on fundamental understanding of structure-function relationships is needed to accelerate materials discovery for CCU in a diverse set of scenarios, and recent developments in this area will also be presented.