Large‐Scale Fabrication of Flexible On‐Chip Micro‐Supercapacitors by a Mechanical Scribing Process

Abstract

AbstractOn‐chip micro‐supercapacitors (MSCs) as efficient miniaturized energy storage devices have attracted great attention for potential application in flexible electronics. In this work, a facile and low cost mechanical scribing method was designed to fabricate flexible all‐solid‐state on‐chip MSCs arrays with ZnCo2O4 nanowires as the interdigitated electrodes, PVA/KOH as solid‐state electrolyte and Ag nanowires as current collector. The fabricated single on‐chip MSC is composed of 10 microelectrodes organized in an interdigitated planar geometry with the area of ∼1.05 cm2. Studies found that a single device can achieve a high areal energy density of 0.065 μWh cm−2 at 0.092 mW cm−2. The mechanical flexibility of the MSC is robust, only 1 % change was observed in capacitance when going through 2000 mechanical bending cycles. Furthermore, a multi‐functional nano/micro‐system was configured by integrating the on‐chip MSC as the energy unit and CdS nanowire‐based photodetector as the functional detecting unit. In the integrated system, the on‐chip MSC provides similar power supplier for the photodetectors as the conventional external energy unit, demonstrating the feasibility and potential application of the on‐chip MSCs for next generation flexible electronics.