(48g) High-Throughput Design of Phase Transition CO2 Sorbents for Green Hydrogen Generation

The demand for green hydrogen is growing rapidly, and it becomes vital to develop cost-effective methods to produce green hydrogen. Conventional biomass-based hydrogen production methods mainly rely on gasification. However, biomass gasification is energy-intensive and requires multiple gas conditioning and separation steps. Here we proposed high temperature perovskite-based sorbents for in-situ CO₂ removal, enabling sorption-enhanced reforming and gasification (SERG) under isothermal conditions. This unique capability for isothermal CO₂ capture and release is enabled by the facile phase transition by the sorbents in response to the external environment. The mixed oxides that can decompose and carbonate with CO₂, effectively intensifies hydrogen production from various biogenic feedstocks. Perovskite-structured sorbents offer excellent compositional flexibility. To search for effective CO₂ sorbents for SERG, we performed a high-throughput screening of 1225 A/B-site doped SrFeO_3-δ perovskite structures using the first-principle calculations to identify suitable sorbent compositions. The screening workflow ensures the geometric stability and thermodynamic favorability for isothermal SERG, and 283 materials satisfy all the screening criteria. Extensive experiments were also carried out based on the finding from the prediction, and we successfully validated the effectiveness of the computation-guided sorbent design framework: most perovskite phases predicted to be active showed CO₂ uptake and release capacities and some exhibited excellent sorption capacities with reversible carbonation of nearly 80% of the A-site cation. By combining simulation and experimental results, an effective thermodynamic descriptor for CO₂ capacity was proposed and it is highly correlated with CO₂ capacity. We also developed screening criteria to optimize operating conditions and the model successfully predict the efficiency of CO₂ capture and O₂ utilization. In summary, we show the applicability of high-throughput screening and theoretical calculations in the phase transition sorbent design, and such strategies are promising to accelerate the discovery of novel materials in other related fields.