Picosecond ultraviolet laser patterned in-plane asymmetric micro-supercapacitors with high-precision capacity matching

In-plane asymmetric micro-supercapacitors (AMSCs) are currently a topic of extensive exploratory research aimed at developing various fabrication techniques for in-plane electrodes and expanding the operating potential window (OPW) to streamline the manufacturing process and increase energy density. Herein, we prepare MXene (Ti₃C₂T_x) and laser induced graphene (LIG) electrodes using picosecond ultraviolet laser etching and laser direct writing techniques, respectively, to construct in-plane MXene//LIG AMSCs. The high precision of laser technology enables us to obtain in-plane asymmetric electrodes with an interelectrode spacing of 100 μm. Additionally, we adjust the interdigital width ratio of the positive and negative electrodes for accurate capacity matching during the construction of asymmetric electrodes. The capacity matching method not only broadens voltage window to 1.2 V, but also increase the energy density to 1.9 times that of before accurate matching. It is expected that the picosecond laser patterned construction approach and the capacity matching method used for MXene//LIG AMSCs will provide new perspectives for in-plane asymmetric supercapacitors.