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Biocompatible materials are expected to play important roles in biomedical applications. In particular, dipeptide nanostructures have attracted considerable attention because of their biocompatibility, functional molecular recognition, and unique biological and electronic properties. Nevertheless, a lack of mass production and facile fabrication of the stable peptide nanostructure array is one of the major hurdles holding back the practical applications. This study developed a simple and wafer-scale process to produce a cyclo-diphenylalanine (Cyclo-FF) nanowire array via a thermal evaporation process and fabricated Cyclo-FF-based triboelectric energy generators (TEG) with high performance. This approach allowed control of the dimensions of the Cyclo-FF nanowires and the preparation of stable peptide nanostructures under ambient conditions and moisture. The Cyclo-FF nanowires were employed as triboelectric materials for biocompatible nanogenerators, which exhibited high-performance power outputs for future applications. The voltage and current output reached ~ 350 V and ~ 10 μA, respectively, with a surface treatment, which was sufficient to light up over a hundred LEDs. Even after dipping Cyclo-FF nanowires in water or TBS buffer solution, it still worked as a TEG material with minor degradation. This method is compatible for the synthesis of bionanomaterials over a large area, and thus can be a powerful strategy to fabricate high-performance biocompatible energy devices for a range of practical applications in the future.

The remote epitaxy of GaN p–n homojunction microcrystals (μCs) is demonstrated for fabricating transferable, flexible white light-emitting diodes (WLEDs). The GaN p–n junction μCs are randomly grown on graphene-coated Al2O3(0001), which are then delaminated for mass-transfer onto conducting copper tape. The μCs-LED shows electrical rectification and white electroluminescence (EL) emission. The μCs-WLED exhibits reliable LED performances after repetitive bending deformations and cycling temperature environments. Based on the transferability, the μCs-WLEDs are patterned and assembled to matrix arrays, which exhibit homogeneous, reliable performances even at a bent form. We discuss that the origin of white EL emission is mixing of blue and yellow–red EL emissions from p-GaN and n-GaN sides, respectively, based on photoluminescence spectroscopic measurements. This study opens a way of fabricating the transferable, flexible, and modular light panels through remote epitaxy.