Designing porous structures and active sites in carbon-based electrocatalysts

This chapter discusses the design of active sites and porous nanostructures of carbon-based electrocatalysts, where various metal-free and noble-metal-free, carbon-based nanostructures have been developed for the electrocatalytic oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) reactions. The introduction of heteroatoms and metal atoms into carbon frameworks can induce electron modulation and thus offers desirable electronic structures for the ORR process. The electrocatalytic HER activity of the catalysts can be quantified by analyzing the free energy of hydrogen adsorption. The metal-free or noble-metal-free porous carbon nanostructures have been intensively studied as ORR and HER electrocatalysts to replace the Pt noble metal. In addition to the electrocatalytic ORR and HER, porous carbon catalysts are also drawing increasing attentions for application to other electrocatalytic reactions including oxygen evolution reaction (OER), CO² reduction, and photoelectrocatalytic water splitting.