Fig. 1: Preparation and material characterization of the metallic glass material.

a Fabrication of the metallic glass ribbon. X-ray diffraction patterns of b Zr₄₅Cu₄₀Al₁₅, c Zr₄₅Cu₃₅Al₂₀ and d Zr₅₀Cu₄₀Al₁₀ and corresponding diffraction images as insets. e Atomic structure of (i) Cu and (ii) metallic glass. f Factors for evaluating the output performance of TENG based on metallic glass. g Photographs of the as-received Zr₄₅Cu₄₀Al₁₅ ribbon. Scale bar = 1 cm. h Optical surface profiler images of scratches after sliding-mode indentation of Zr₄₅Cu₄₀Al₁₅ (top) and Cu (bottom). i Mechanical properties of different samples. j Density and k atomic density of different samples. l Friction coefficient of different MG samples and Cu. Error bar comes from the standard deviation of repeat experiments larger than 5 times. Source data are provided as a Source Data file.