Synthesis and Electrochemical Properties of Hierarchical Nanoporous Carbon Architectures

S.K. Nune, P. Meduri, J.P. Lemmon
Pacific Northwest National Laboratory, US

Keywords: supercapacitors, surface area, metal organic frameworks

Summary:

Supercapacitors with high power density in combination with batteries with high energy density can lead to efficient energy storage systems. Recent studies from NREL have shown that HEVs equipped with 40-100 Wh/kg supercapacitors could improve fuel efficiency by 15-30%. However, energy density of state-of-the-art capacitors (2-20 Wh/kg) is an order of magnitude lower than metal hydride (40-100 Wh/kg) and Li-ion batteries (120-170 Wh/kg). The key scientific barrier for low capacitances is the presence of micropores on the active surface of electrodes that are not accessible to electrolytes. We will present our results on controlled synthesis and electrochemical studies of hierarchical nanoporous carbon architectures derived from “metal organic frameworks (MOFs)”. MOFs represent a new class of materials with well-defined porosity, structure tailorability and tunable functionality with considerable attention due to their promise in wide range of applications. Porous carbons derived from MOFs (CMOFs) exhibited high surface area, porosity and pore volume. To further improve the overall electrical conductivity of CMOFs, heteroatoms such as nitrogen can be introduced using amine linkers during MOF synthesis. Detailed synthesis strategies, effect of annealing temperature on the CMOFs structure and their electrochemical performances as materials for supercapacitors will be discussed.