Organic and Carbon Aerogels

Abstract

Organic aerogels based on the reaction of resorcinol and formaldehyde were developed in 1989 by Richard W. Pekala. Due to very attractive properties such as low density, high specific surface area and high porosity, and low thermal conductivity research on organic aerogels was rapidly growing. This chapter describes the synthesis of different organic aerogels, the influence of synthesis parameters and properties of final aerogels. The application field of organic aerogels is very broad. On of the first applications was the usage as a precursor for carbon aerogels. Well adjustable properties and microstructure of carbon aerogels made them very attractive. Due to low thermal conductivity, organic aerogels are also used as a thermal insulator. The doping with heteroatoms opens new application in catalysis, absorption of liquids or trapping from metals. Thermal treatment of organic aerogels under inert gas conditions leads to carbon aerogels. The process parameters of carbonization strongly influence the properties and microstructure of aerogels. The duration, temperature and gases effect both particle as well as pore size in the aerogel network. Thermal and chemical activations of aerogels result in a very high specific surface area and micro pore volume. Carbon aerogels are suitable materials for a wide spectrum of applications due to their unique structure and excellent properties. The focus of this chapter is on the applications for supercapacitors and batteries. Among others, diverse applications such as catalysis on doped aerogels, hydrogen storage, foundry and thermal insulation are discussed here.