title: Superior Electrical Conductivity in Hydrogenated Layered Ternary Chalcogenide Nanosheets for Flexible All-Solid-State Supercapacitors.
abstract: As the properties of ultrathin two-dimensional (2D) crystals are strongly related to their electronic structures, more and more attempts were carried out to tune their electronic structures to meet the high standards for the construction of next-generation smart electronics. Herein, for the first time, we show that the conductive nature of layered ternary chalcogenide with formula of Cu2 WS4 can be switched from semiconducting to metallic by hydrogen incorporation, accompanied by a high increase in electrical conductivity. In detail, the room-temperature electrical conductivity of hydrogenated-Cu2 WS4 nanosheet film was almost 10(10) times higher than that of pristine bulk sample with a value of about 2.9×10(4)  S m(-1) , which is among the best values for conductive 2D nanosheets. In addition, the metallicity in the hydrogenated-Cu2 WS4 is robust and can be retained under high-temperature treatment. The fabricated all-solid-state flexible supercapacitor based on the hydrogenated-Cu2 WS4 nanosheet film shows promising electrochemical performances with capacitance of 583.3 F cm(-3) at a current density of 0.31 A cm(-3) . This work not only offers a prototype material for the study of electronic structure regulation in 2D crystals, but also paves the way in searching for highly conductive electrodes.
authors.affiliation: Hefei National Laboratory for Physical Science at Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026, P.R. China.
authors.forename: Xin
authors.initials: X
authors.lastname: Hu
authors.affiliation: Hefei National Laboratory for Physical Science at Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Shao
authors.affiliation: Hefei National Laboratory for Physical Science at Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026, P.R. China.
authors.forename: Xudong
authors.initials: X
authors.lastname: Hang
authors.affiliation: Hefei National Laboratory for Physical Science at Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026, P.R. China. zhxid@ustc.edu.cn.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Hefei National Laboratory for Physical Science at Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026, P.R. China.
authors.forename: Wenguang
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Hefei National Laboratory for Physical Science at Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026, P.R. China. yxie@ustc.edu.cn.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xie
keywords: all-solid-state supercapacitor; electrical conductivity; hydrogen incorporation; nanosheets; ternary chalcogenides