Book excerpt: There are a large number of books available on fuel cells; however, the majority are on specific types of fuel cells such as solid oxide fuel cells, proton exchange membrane fuel cells, or on specific technical aspects of fuel cells, e.g., the system or stack engineering. Thus, there is a need for a book focused on materials requirements in fuel cells. Key Materials in Low-Temperature Fuel Cells is a concise source of the most important and key materials and catalysts in low-temperature fuel cells. A related book will cover key materials in high-temperature fuel cells. The two books form part of the "Materials for Sustainable Energy & Development" series. Key Materials in Low-Temperature Fuel Cells brings together world leaders and experts in this field and provides a lucid description of the materials assessment of fuel cell technologies. With an emphasis on the technical development and applications of key materials in low-temperature fuel cells, this text covers fundamental principles, advancement, challenges, and important current research themes. Topics covered include: proton exchange membrane fuel cells, direct methanol and ethanol fuel cells, microfluidic fuel cells, biofuel cells, alkaline membrane fuel cells, functionalized carbon nanotubes as catalyst supports, nanostructured Pt catalysts, non-PGM catalysts, membranes, and materials modeling. This book is an essential reference source for researchers, engineers and technicians in academia, research institutes and industry working in the fields of fuel cells, energy materials, electrochemistry and materials science and engineering.