Carbon Nanostructures for Flexible and Lightweight Fuel Cells

Fuel cells generate heat and power as long as fuel is available, unlike batteries, which need external electrical input. Two electrodes – an anode (negative) and a cathode (positive) are stacked around an electrolyte to make up a fuel cell. Due to their low emission of pollutants, they have a high chance of replacing nonrenewable energy sources such as fossil fuels. Carbon and its different forms including graphene, graphene oxide, reduced graphene oxide, carbon black, graphitic carbon nitride, and allotropes such as carbon nanotubes with single and multiwalled structures all come under a family of efficient catalysts, which are at present used in the fuel cell technology either in some or almost all parts of the fuel cell. They are fabricated in their pristine form or added as supports to withhold the structure, enhance the electrochemical performance, provide mechanical strength, and also increase the durability of the fuel cells. Flexible and lightweight fuel cells are the hot topic of the era to be visually implemented in portable electronic devices designed mainly for the comfort and accessibility of mankind, one such example being sweatbands. This chapter focuses on the performance of carbon nanostructures and their diverse allotropes that are employed on different parts of a fuel cell for the efficient functioning and advancement of various types of flexible fuel cells.