Biomimetic MXene Textures with Enhanced Light-to-Heat Conversion for Solar Steam Generation and Wearable Thermal Management

2D materials are of particular interest in light-to-heat conversion, yet challenges remain in developing a facile method to suppress their light reflection. Herein, inspired by the black scales of Bitis rhinoceros, a generalized approach via sequential thermal actuations to construct biomimetic 2D-material nanocoatings, including Ti₃C₂T_x MXene, reduced graphene oxide (rGO), and molybdenum disulfide (MoS₂) is designed. The hierarchical MXene nanocoatings result in broadband light absorption (up to 93.2%), theoretically validated by optical modeling and simulations, and realize improved light-to-heat performance (equilibrium temperature of 65.4 °C under one-sun illumination). With efficient light-to-heat conversion, the bioinspired MXene nanocoatings are next incorporated into solar steam-generation devices and stretchable solar/electric dual-heaters. The MXene steam-generation devices require much lower solar-thermal material loading (0.32 mg cm⁻²) and still guarantee high steam-generation performance (1.33 kg m⁻² h⁻¹) compared with other state-of-the-art devices. Additionally, the mechanically deformed MXene structures enable the fabrication of stretchable and wearable heaters dual-powered by sunlight and electricity, which are reversibly stretched and heated above 100 °C. This simple fabrication process with effective utilization of active materials promises its practical application value for multiple solar–thermal technologies.