Magnetic-enhanced Pd/MXene@Ni foam for formic acid dehydrogenation via photothermal interface

Hydrogen is considered a promising energy carrier for renewable energy systems. Formic acid (FA) stands out among various liquid hydrogen storage carriers due to its mild dehydrogenation reaction temperature, which makes it suitable for solar-driven photothermal dehydrogenation, enabling hydrogen production with minimal external energy input. Nevertheless, there are still issues with the photothermal dehydrogenation of FA, including low photothermal conversion efficiency, unstable solar heating, and uneven temperature distribution of the catalyst. This study designs a magnetic photothermal catalytic converter (MPC) using Pd/MXene catalyst. Under a light intensity of 900 mW·cm^-2, the system achieves a hydrogen evolution rate of 491 mmol·g^-1·h^-1 with a H₂ selectivity of 93.8%. Meanwhile, the nickel component in the MPC enables rapid temperature rise and promotes dehydrogenation under magnetic induction. Under magnetic induction heating, the system reaches a hydrogen evolution rate of 1070 mmol·g^-1·h^-1 and a H₂ selectivity of 94.3%, with a significantly higher hydrogen yield than that under photothermal conditions. Furthermore, a multi-physics coupled model of the reactor was developed and experimentally validated to investigate the heat transfer processes. Finally, to optimize performance across different application scenarios, a comprehensive dehydrogenation performance indicator was established. This work provides guidance for the practical application of FA dehydrogenation under the photothermal and magnetic fields.