title: S, N-Co-Doped Graphene-Nickel Cobalt Sulfide Aerogel: Improved Energy Storage and Electrocatalytic Performance.
abstract: Metal sulfides are commonly used in energy storage and electrocatalysts due to their redox centers and active sites. Most literature reports show that their performance decreases significantly caused by oxidation in alkaline electrolyte during electrochemical testing. Herein, S and N co-doped graphene-based nickel cobalt sulfide aerogels are synthesized for use as rechargeable alkaline battery electrodes and oxygen reduction reaction (ORR) catalysts. Notably, this system shows improved cyclability due to the stabilization effect of the S and N co-doped graphene aerogel (SNGA). This reduces the rate of oxidation and the decay of electronic conductivity of the metal sulfides materials in alkaline electrolyte, i.e., the capacity decrease of CoNi2S4/SNGA is 4.2% for 10 000 cycles in a three-electrode test; the current retention of 88.6% for Co-S/SNGA after 12 000 s current-time chronoamperometric response in the ORR test is higher than corresponding Co-S nanoparticles and Co-S/non-doped graphene aerogels. Importantly, the results here confirm that the Ni-Co-S ternary materials behave as an electrode for rechargeable alkaline batteries rather than supercapacitors electrodes in three-electrode test as commonly described and accepted in the literature. Furthermore, formulas to evaluate the performance of hybrid battery devices are specified.
authors.affiliation: Christopher Ingold Laboratory Department of Chemistry University College London 20 Gordon Street London WC1H 0AJ UK.
authors.forename: Guanjie
authors.initials: G
authors.lastname: He
authors.affiliation: School of Engineering and Materials Science/Materials Research Institute Queen Mary University of London Mile End Road E14NS London UK.
authors.forename: Mo
authors.initials: M
authors.lastname: Qiao
authors.affiliation: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University Shanghai 201620 China.
authors.forename: Wenyao
authors.initials: W
authors.lastname: Li
authors.affiliation: Christopher Ingold Laboratory Department of Chemistry University College London 20 Gordon Street London WC1H 0AJ UK.
authors.forename: Yao
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Christopher Ingold Laboratory Department of Chemistry University College London 20 Gordon Street London WC1H 0AJ UK.
authors.forename: Tingting
authors.initials: T
authors.lastname: Zhao
authors.affiliation: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University Shanghai 201620 China.
authors.forename: Rujia
authors.initials: R
authors.lastname: Zou
authors.affiliation: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University Shanghai 201620 China.
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.affiliation: Christopher Ingold Laboratory Department of Chemistry University College London 20 Gordon Street London WC1H 0AJ UK.
authors.forename: Jawwad A
authors.initials: JA
authors.lastname: Darr
authors.affiliation: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University Shanghai 201620 China.
authors.forename: Junqing
authors.initials: J
authors.lastname: Hu
authors.affiliation: School of Engineering and Materials Science/Materials Research Institute Queen Mary University of London Mile End Road E14NS London UK.
authors.forename: Maria-Magdalena
authors.initials: MM
authors.lastname: Titirici
authors.affiliation: Christopher Ingold Laboratory Department of Chemistry University College London 20 Gordon Street London WC1H 0AJ UK.
authors.forename: Ivan P
authors.initials: IP
authors.lastname: Parkin
keywords: aerogel; nickel cobalt sulfide; oxygen reduction reaction; rechargeable alkaline battery