Fig. 13. Applications of Cu NW TEs. (a) Characteristic I–V curves of solar cells with ITO or a Cu NW film as the transparent electrode. The inset shows the photograph of a flexible solar cell.¹⁰⁰ (b) Demonstration of a touch-screen panel fabricated with a laser-nanowelded Cu NW TE.¹⁰⁶ (c) Application of Cu NW/PU conductors in a strain sensor recording the relative resistance response of Cu NW/PU conductors to the bending and releasing of a finger.¹⁰⁸ (d) Temperature profiles as a function of applied voltage of 3, 5, and 7 V on the Cu NW/PU heater. (e) Optical image of the blue light electroluminescence of an InGaN-based LED with Cu NW TEs.⁹⁵ (f) An as-prepared mixed transparent electrode composed of a pure Cu NW film (left) and RGO/Cu NW film (right). The initial (coloured) state (right-top) and bleached state (right-bottom) of PB deposited on the mixed electrode.¹²⁸.