A Highly Stretchable Microsupercapacitor Using Laser‐Induced Graphene/NiO/Co<sub>3</sub>O<sub>4</sub> Electrodes on a Biodegradable Waterborne Polyurethane Substrate
Wentao Wang, Longsheng Lu, Yingxi Xie, Wei Yuan, Zhenping Wan, Yong Tang, Kwok Siong Teh
Abstract
Abstract Constructing microsupercapacitors (MSCs) with an outstanding stretchability is urgent for wearable electronics, and an intrinsic biodegradability is also meaningful. Herein, laser‐induced graphene/NiO/Co 3 O 4 (NiO/Co 3 O 4 /LIG) is in situ synthesized on a polyimide (PI) film during laser processing, then the electrodes are transferred to a biodegradable waterborne polyurethane (WPU) substrate to fabricate stretchable MSCs. Experimentally, the as‐prepared stretchable MSCs exhibit an excellent areal capacitance of 2.4 mF cm −2 , high capacitance retention of 77.1% at 50% strain, and capacitance degradation of less than 19.8% after 1000 stretching cycles. These desirable properties are mainly attributed to the gradient structure of NiO/Co 3 O 4 /LIG, the synergistic effect of hybrid NiO/Co 3 O 4 nanoparticles, and the intensive interface adhesion between the electrodes and WPU. Interestingly, the robust function of stretchable MSCs is further presented by using them to power a microsensor and assembling them with triboelectric nanogenerators to generate power from mechanical contact with skin, which makes the stretchable MSCs promising as a sustainable driving source for wearable electronics.