title: Synthesis and Electrochemical Properties of Two-Dimensional Hafnium Carbide.
abstract: We demonstrate fabrication of a two-dimensional Hf-containing MXene, Hf3C2Tz, by selective etching of a layered parent Hf3[Al(Si)]4C6compound. A substitutional solution of Si on Al sites effectively weakened the interfacial adhesion between Hf-C and Al(Si)-C sublayers within the unit cell of the parent compound, facilitating the subsequent selective etching. The underlying mechanism of the Si-alloying-facilitated etching process is thoroughly studied by first-principles density functional calculations. The result showed that more valence electrons of Si than Al weaken the adhesive energy of the etching interface. The MXenes were determined to be flexible and conductive. Moreover, this 2D Hf-containing MXene material showed reversible volumetric capacities of 1567 and 504 mAh cm-3for lithium and sodium ions batteries, respectively, at a current density of 200 mAg-1after 200 cycles. Thus, Hf3C2TzMXenes with a 2D structure are candidate anode materials for metal-ion intercalation, especially for applications where size matters.
authors.affiliation: Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.|University of Chinese Academy of Sciences , 19A Yuquan Road, Shijingshan District, Beijing 100049, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Xianhu
authors.initials: X
authors.lastname: Zha
authors.affiliation: Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Fanyan
authors.initials: F
authors.lastname: Chen
authors.affiliation: Energy Storage Division, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Guoliang
authors.initials: G
authors.lastname: Gao
authors.affiliation: Energy Storage Division, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Shuwei
authors.initials: S
authors.lastname: Wang
authors.affiliation: Energy Storage Division, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Cai
authors.identifier: 0000-0001-5825-4028
authors.initials: C
authors.lastname: Shen
authors.affiliation: Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Tao
authors.identifier: 0000-0001-9704-9545
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Physics and Material Science, City University of Hong Kong , Kowloon, Hong Kong SAR China.
authors.forename: Chunyi
authors.identifier: 0000-0001-6766-5953
authors.initials: C
authors.lastname: Zhi
authors.affiliation: Thin Film Physics Division, Linköping University, IFM , 581 83 Linköping, Sweden.
authors.forename: Per
authors.identifier: 0000-0003-1785-0864
authors.initials: P
authors.lastname: Eklund
authors.affiliation: Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Shiyu
authors.identifier: 0000-0001-6707-3915
authors.initials: S
authors.lastname: Du
authors.affiliation: State Key Laboratory of Nuclear Physics and Technology, CAPT and IFSA Collaborative Innovation Center of MoE, Peking University , Beijing 100871, China.
authors.forename: Jianming
authors.initials: J
authors.lastname: Xue
authors.affiliation: Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Weiqun
authors.identifier: 0000-0001-9929-9732
authors.initials: W
authors.lastname: Shi
authors.affiliation: Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Chai
authors.affiliation: Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
authors.forename: Qing
authors.identifier: 0000-0001-7083-9416
authors.initials: Q
authors.lastname: Huang
keywords: 2D materials; DFT calculations; MXenes; electrochemical properties; selective etching