Full laser irradiation processed Pb-graphene nanocomposite electrodes toward the manufacturing of high-performance supercapacitors

Facile and scalable manufacturing of metal decorated carbon electrodes is highly expected for next-generation energy-storage devices. Inspired by unique processing characteristics of laser-induced graphene (LIG) as well as electrochemical advantages of Pb, a full-laser protocol is developed for assembling Pb doped LIG (Pb-LIG) electrodes through two separate laser-irradiation processes to selectively irradiate polyimide (PI) for forming graphene framework and to selectively melt-and-recrystallize Pb powders. Along with high-efficient production and customizable sizes and shapes, Pb dosage and laser power are systematically investigated as two critical parameters to understand the process-structure relationship. By simultaneously considering the two factors, an interesting two-regime effect has been discovered, which is guiding for achieving optimized Pb content of 77.77 wt% as long as laser fluence per Pb dosage is around 100 J mg⁻¹. Owing to clear redox faraday reaction, the integrated Pb content is indeed fundamental for promoting capacitive performance, by realizing a six-fold enhancement of areal capacitance from 25 to 128 mF cm⁻². Finally, multiple Pb-LIG supercapacitors are facilely combined either in series or in parallel to expand its performance for energy-storage applications.