Stable gas nuclei accelerating the amine regeneration for energy-efficient CO2 capture

Chemical absorption with amines offers an attractive solution for large-scale carbon mitigation, but its practical application is impeded by high regeneration energy consumption. Despite extensive efforts to accelerate regeneration through chemical catalysis, inefficient gas-liquid mass transfer during desorption remains a major bottleneck. Herein, we report a microcavity-engineered desorption packing fabricated via nanosecond laser etching to promote bubble nucleation and release. Benefiting from the enhanced mass transfer, the optimized desorption packing enhances the maximum desorption rate by 92.2% and reduces the relative heat duty by 35.8% compared to the blank case, without significant performance degradation after multiple desorption cycles. Mechanistic studies show that the laser-induced microcavities can entrap gas to form stable gas nuclei sites, reducing the supersaturation barrier for bubble nucleation and thus accelerating the amine regeneration. The universality of this microcavity engineering strategy is demonstrated by its successful implementation on different substrate materials, including Ni, Ti, and Fe. This study provides new ideas for the design and fabrication of highly efficient desorption packings.