a, Exploded view of EC-EYE. b, c, Side view (b) and top view (c) of a completed EC-EYE. d, Low-resolution cross-sectional SEM image of the hemispherical PAM/nanowires. e, Cross-sectional SEM images of nanowires in PAM. f, High-resolution transmission electron microscopy image of a single-crystalline perovskite nanowire. g, Photograph of the polydimethylsiloxane (PDMS) socket, which improves the alignment of the liquid-metal wires.