Shapeshifting exsolved FeNi bimetallic nanostructures as catalytic switchers during the CO2-mediated ethane conversion

Abstract In the era of the energy transition, the development of sustainable, high-performance, and multifunctional catalysts that adapt to complex catalytic processes is essential. Here, we report shapeshifting bimetallic iron–nickel catalysts developed via an exsolution strategy for carbon dioxide–mediated ethane conversion. By controlling the reduction temperature of a perovskite host, either alloyed iron–nickel nanoparticles or oxide–alloy core–shell nanoparticles are selectively formed. Oxidative regeneration of the perovskite enables reversible interconversion between these distinct nanostructures within the same parent material. As a result, the catalyst exhibits switchable selectivity between ethane dry reforming and carbon dioxide–assisted oxidative dehydrogenation while maintaining high stability. Repeated redox cycling confirms that the structural transformation and catalytic performance are largely reversible. These results demonstrate that exsolution provides a robust platform for designing regenerable catalysts with deliberately tunable and switchable catalytic states.