High-energy all-in-one stretchable micro-supercapacitor arrays based on 3D laser-induced graphene foams decorated with mesoporous ZnP nanosheets for self-powered stretchable systems

Abstract

Micro-supercapacitors are promising energy storage devices that can complement or even replace lithium-ion batteries in wearable and stretchable microelectronics. However, they often possess a relatively low energy density and limited mechanical stretchability. Here, we report an all-in-one planar micro-supercapacitor arrays (MSCAs) based on hybrid electrodes with ultrathin ZnP nanosheets anchored on 3D laser-induced graphene foams (ZnP@LIG) arranged in island-bridge device architecture. The hybrid electrodes with a large specific surface area demonstrate excellent ionic and electrical conductivities, impressive gravimetric (areal) capacitance of 1425 F g −1 (7.125 F cm −2 ) at 1 A g −1 , and long-term stability. In addition to high energy (245 m Wh cm −2 ) and power (12.50 mW kg −1 at 145 m Wh cm −2 ) densities, the MSCAs with excellent cycling stability also showcase adjustable voltage and current outputs through serial and parallel connections of MSC cells in the island-bridge design, which also allows the system to be reversibly stretched up to 100%. Meanwhile, theoretical calculations validated by UV–vis absorption spectra partially suggest that the enhanced capacitance and rate capability may result from the improved electrical conductivity and number of adsorbed charged ions (Na + in Na 2 SO 4 aqueous electrolyte and K + in PVA/KCl gel electrolyte) on the pseudocapacitive non-layered ultrathin ZnP nanosheets. The integration of the all-in-one stretchable MSCAs with a crumpled Au-based triboelectric nanogenerator and stretchable crumpled graphene-based strain sensor demonstrates a self-powered stretchable system. The coupled design principle of electronic materials and device architecture provides a promising method to develop high-performance wearable/stretchable energy storage devices and self-powered stretchable systems for future bio-integrated electronics. • We report hybrid electrodes with ZnP nanosheets anchored on 3D laser-induced graphene foams. • The hybrid electrodes exhibit excellent ionic/electrical conductivities and long-term stability. • The hybrid electrodes with stretchable structures enable stretchable micro-supercapacitor arrays (MSCAs). • The MSCAs with adjustable voltage/current outputs can be reversibly stretched to 100%. • The integration of MSCAs with TENG and sensors demonstrates a self-powered stretchable system.