Biomass-Derived Carbons as Versatile Materials for Energy-Related Applications: Capacitive Properties vs. Oxygen Reduction Reaction Catalysis
Sprache des Titels:
Englisch
Original Kurzfassung:
Biomass-derived carbons are very attractive materials due to the possibility of tuning
their properties for different energy-related applications. Various pore sizes, conductivities and
the inherent presence of heteroatoms make them attractive for different electrochemical reactions,
including the implementation of electrochemical capacitors or fuel cell electrodes. This contribution
demonstrates how different biomass-derived carbons prepared from the same precursor of viscose
fibers can reach appreciable capacitances (up to 200 F g??1) or a high selectivity for the oxygen
reduction reaction (ORR).We find that a highly specific surface area and a large mesopore volume
dominate the capacitive response in both aqueous and non-aqueous electrolytic solutions. While the
oxygen reduction reaction activity is not dominated by the same factors at low ORR overpotentials,
these take the dominant role over surface chemistry at high ORR overpotentials. Due to the high
selectivity of the O2 reduction to peroxide and the appreciable specific capacitances, it is suggested
that activated carbon fibers derived from viscose fibers are an attractive and versatile material for
electrochemical energy conversion applications.
Forschungs-