H2 chemical storage in e-fuels: novel materials for Power-to-X

The urgent need to mitigate anthropogenic CO2 emissions while ensuring energy security has positioned Carbon Capture Utilisation and Storage (CCUS) technologies as a benchmark for the global energy transition [1]. In the CCU framework, this work reports recent results on CO2 catalytic hydrogenation into high-value energy carriers via Powerto- Methane (PtM) and Power-to-Liquid (PtL) pathways. Integrating advanced catalyst synthesis, multi-scale characterisation, and process simulation, it addresses coupling catalyst architecture and process design to overcome kinetic/thermodynamic barriers in circular carbon systems. For PtM, CO2 methanation under steady-state and ICCU strategies is reported. Ni on USY zeolites showed interesting performance with coke resistance; hierarchical porosity and particle size/dispersion drove the catalytic behavior [2]. Rhenium dual-functional materials decoupled capture/conversion, achieving 100% methane selectivity via site-adsorbent synergy [3]. Conversely, PtL (CO2 to methanol) faced distinct constraints: Cu catalysts are selective only at 150-220°C, beyond which RWGS/methanation dominate [4]. Metal-support interfaces can be tuned via proper selection of precursors. Cu-Fe-Ce/Cu-Fe screening at high pressure favored CO/CH4 over methanol, warranting further study. Selectivity depends on metal composition, redox, and conditions. Overall, effective CO2 utilisation needs integrated catalyst-process design: PtM flexibility suits dynamic regimes; PtL demands precise catalysts + advanced reactors.