Controlled modification of the nanostructure and surface properties of new generation carbon materials
Our group’s interest in carbon is related to many areas of application, including in PEM fuel cells, redox flow batteries, Li ion batteries, capacitors, and as novel filter materials. Our focus is primarily on the following areas.
Nano-structured carbon powders
In recent years, efforts have been focused on understanding and improving the stability of carbon support materials used in PEM fuel cell cathodes. A series of novel carbon nanostructures were thus developed, including ordered mesoporous carbons (OMCs) and a new family of colloid-imprinted carbons (CICs), with some FESEM and tomographic TEM images of these carbons show below.
Using the OMCs, which are in the form of ‘carbon nanostrings’, we have achieved the highest yet reported capacitance per gram of templated carbon. For the CICs, pioneering approaches were developed to fully control their pore diameter and depth, as well as wall thickness, which allowed further insights to be obtained into the impact of distributed potentials through porous layers on the observed kinetics of electrochemical reactions, including oxygen reduction.
Self-supported nanoporous carbon scaffolds
Our group has also recently pioneered the synthesis of self-supporting nanoporous carbon scaffold (NCS) material, using a tape casting method, which is suitable for industrial scale up (patents filed). The scaffolds contain three dimensionally interconnected nanopores, which are adjustable in size, while also having high surface areas (from 100 to 400 m2/g). The thickness of these scaffolds can be controlled from < 1 µm to > 1 mm, while their geometric area can be varied from mm2 to m2 by using different casting parameters. The scaffolds also show very good flexibility/elasticity, as well as good electrical conductivity, of interest especially for electrochemical research. The scaffolds also allow for further surface modification or functionalization, by, for example, grafting chemical moieties or biological species onto their surfaces. Due to these excellent properties, the NCS materials are of interest for a wide range of applications, including in PEM fuel cells, redox flow batteries, batteries, sensors, nano-filters, deionization, water treatment, and so on. Many of these applications are currently under study in the Birss group.
