Nanocarbon-based Bifunctional Electrocatalysts

For the sustainable development of green and clean electrochemical energy technologies, the advancement of high-performance electrode materials is essential. Precious metal catalysts such as those based on Pt, Ir, and Ru show high catalytic performance, but their scarcity and high cost restrict their application in energy technologies. Hence nanocarbon-based bifunctional electrocatalysts have emerged as a promising class of materials that hold the key to addressing critical challenges in energy conversion and storage technologies. Nanocarbon materials, such as carbon nanotubes, graphene, and their derivatives, have shown remarkable electrical conductivity, high surface area, and exceptional chemical stability, making them ideal candidates for electrocatalysis. However, these nanocarbon materials as such are electroneutral and catalytically inactive. Heteroatom doping and functionalization change the electronic properties of the nanocarbons and permit multifunctional electrocatalytic activity. These modified nanocarbons can catalyze the oxygen reduction reaction (ORR), the hydrogen evolution reaction (HER), and the oxygen evolution reaction (OER) in electrochemical systems, making them applicable in fuel cells, water electrolyzers, metal–air batteries, etc. This dual functionality of the materials in energy devices enhances the overall efficiency of energy conversion devices. Applications of nanocarbon-based bifunctional electrocatalysts extend beyond energy storage and conversion, encompassing electrochemical sensors, environmental remediation, etc. The multifunctional nature of nanocarbon materials, coupled with their versatility, holds great promise for developing efficient, durable, and cost-effective electrochemical devices. This chapter provides an insight into the promising field of nanocarbon-based bifunctional electrocatalysts and underscores their significance in shaping a sustainable energy future.