Reactive Laser Additive Manufacturing of Hierarchically Structured Aerogels

ABSTRACT As demands for sustainable and scalable energy materials manufacturing accelerate, additive manufacturing (AM) remains largely limited to passive shaping of predefined precursors. Here, we introduce reactive laser AM, in which precursor composition is designed to transform the printing step itself into a chemically active stage of materials synthesis. Incorporating eutectic alkali halide salts into protein‐based powders converts localized laser heating into transient reaction environments that drive vapor‐phase chemistry, surface etching, and in situ hierarchical growth without external reagents or solvents. This internally activated reactivity enables the rapid formation of graphitic aerogel monoliths with multilevel architecture—macroporous frameworks decorated with microtubular arrays and nanoscale features—within seconds in a single process. As energy storage electrodes, these hierarchically structured aerogels exhibit a tenfold enhancement in gravimetric capacitance (∼162 F g −1 ) relative to salt‐free counterparts. By engineering reactivity through feedstock design, this work reframes laser AM as a dynamic platform for reaction‐driven materials‐by‐design.