Michael Pope1
University of Waterloo1
Infrared (IR) lasers, such as the carbon dioxide laser popularly used by hobbyists and various industries for precision cutting and marking/engraving, are increasingly employed in the conversion of carbonaceous precursors into a mesoporous graphene-like carbon material, known as laser-induced graphene (LIG). In this presentation, I will delve into my research group's recent explorations into the potentials and limitations of utilizing this technique to create electrodes for batteries and supercapacitors. Our focus centers on the carbon precursor polyfurfuryl alcohol (PFA), a common component for crafting glassy carbon electrodes, derived from waste biomass. By amalgamating PFA with IR transparent salts, we aim to extend the laser's penetration depth, thus producing electrodes with an enhanced surface area or greater areal mass loading. Our findings reveal that typical salts, such as sodium chloride or sodium sulfate, not only achieve these objectives but also serve a dual role as a templating and doping agent, markedly improving the areal capacitance of symmetric supercapacitors. Furthermore, by incorporating this system with metal salts or catalyst precursors, we engineer unique compositions and nanostructures exhibiting significant electrochemical activity towards the oxygen reduction reaction. Our studies show that the process of direct laser writing on air-cathodes is a superior method to develop high-performance zinc-air batteries.