Photonic nanomanufacturing of high performance energy device on flexible substrate

With the developing of wearable electronics and information society, integrated energy storage devices are urgently demanded to be integrated on flexible substrates. We successfully demonstrated using direct laser-reduction of the hydrated GO and chloroauric acid (HAuCl4) nanocomposite to fabricate in-plane micro-supercapacitors (MSCs) with fast ion diffusion on paper. The electrode conductivity of these flexible nanocomposites reaches up to 1.1 x 10⁶ S m^-1, which enhances superior rate capability of micro-supercapacitors, and large specific capacitances of 0.77 mF cm^-2 (17.2 F cm^-3 for volumetric capacitance) at 1 V s^-1, and 0.46 mF cm^-2 (10.2 F cm^-3) at 100 V s^-1. We also have demonstrated that pulsed laser irradiation rapidly converts the polyimide (PI) sheets into an electrically conductive porous carbon structure in ambient conditions. The specific capacitance of single layer surface supercapacitors can reach 20.4 mF/cm² at 0.1 mA/cm² discharge current density. Furthermore, we successfully fabricate the multi-layer supercapacitor with the PI substrate using 3D femtosecond laser direct writing, and the specific capacitances of three layers supercapacitors is 37.5 mF/cm².