TY - JOUR
T1 - Comparison of Two-Dimensional Transition Metal Dichalcogenides for Electrochemical Supercapacitors
AU - Bissett, M.A.
AU - Worrall, S.D.
AU - Kinloch, I.A.
AU - Dryfe, R.A.W.
N1 - ©2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
PY - 2016/5/20
Y1 - 2016/5/20
N2 - Layered two-dimensional (2D) materials such as transition metal dichalcogenides (TMDCs) are receiving increased interest for applications in energy storage due to their high specific surface area and versatile electronic structure. In this work, we prepare solvent stabilised dispersions of a variety of few-layer thick TMDC crystals (MoS2, MoSe2, WS2, and TiS2) by ultrasonication. The exfoliated materials were first characterised by a variety of techniques to determine their quality. These dispersions were then used to form supercapacitor electrodes by filtration, without use of any further conductive additives or polymeric binders. These thin layer TMDC electrodes were assembled into symmetrical coin-cell devices for comparative electrochemical testing. It was found that despite being the most widely studied material, MoS2 suffers from inferior charge storage properties compared to the much higher conductivity and lower density TiS2. Impedance spectroscopy was used to investigate the charge storage mechanisms inside the coin cells, which were found to consist of a combination of both rapid, but low magnitude, electric double layer capacitance and much slower, but higher magnitude, ion adsorption pseudocapacitance.
AB - Layered two-dimensional (2D) materials such as transition metal dichalcogenides (TMDCs) are receiving increased interest for applications in energy storage due to their high specific surface area and versatile electronic structure. In this work, we prepare solvent stabilised dispersions of a variety of few-layer thick TMDC crystals (MoS2, MoSe2, WS2, and TiS2) by ultrasonication. The exfoliated materials were first characterised by a variety of techniques to determine their quality. These dispersions were then used to form supercapacitor electrodes by filtration, without use of any further conductive additives or polymeric binders. These thin layer TMDC electrodes were assembled into symmetrical coin-cell devices for comparative electrochemical testing. It was found that despite being the most widely studied material, MoS2 suffers from inferior charge storage properties compared to the much higher conductivity and lower density TiS2. Impedance spectroscopy was used to investigate the charge storage mechanisms inside the coin cells, which were found to consist of a combination of both rapid, but low magnitude, electric double layer capacitance and much slower, but higher magnitude, ion adsorption pseudocapacitance.
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84964037810&partnerID=MN8TOARS
UR - https://www.sciencedirect.com/science/article/pii/S0013468616307733?via%3Dihub
U2 - 10.1016/j.electacta.2016.03.190
DO - 10.1016/j.electacta.2016.03.190
M3 - Article
SN - 0013-4686
VL - 201
SP - 30
EP - 37
JO - Electrochimica Acta
JF - Electrochimica Acta
ER -