title: A facile and universal top-down method for preparation of monodisperse transition-metal dichalcogenide nanodots.
abstract: Despite unique properties of layered transition-metal dichalcogenide (TMD) nanosheets, there is still lack of a facile and general strategy for the preparation of TMD nanodots (NDs). Reported herein is the preparation of a series of TMD NDs, including TMD quantum dots (e.g. MoS2 , WS2 , ReS2 , TaS2 , MoSe2 and WSe2 ) and NbSe2 NDs, from their bulk crystals by using a combination of grinding and sonication techniques. These NDs could be easily separated from the N-methyl-2-pyrrolidone when post-treated with n-hexane and then chloroform. All the TMD NDs with sizes of less than 10 nm show a narrow size distribution with high dispersity in solution. As a proof-of-concept application, memory devices using TMD NDs, for example, MoSe2 , WS2 , or NbSe2 , mixed with polyvinylpyrrolidone as active layers, have been fabricated, which exhibit a nonvolatile write-once-read-many behavior. These high-quality TMD NDs should have various applications in optoelectronics, solar cells, catalysis, and biomedicine.
authors.affiliation: Energy Research Institute @ NTU (ERI@N), Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553 (Singapore); School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore) http://www.ntu.edu.sg/home/hzhang/
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.forename: Zhuangchai
authors.initials: Z
authors.lastname: Lai
authors.forename: Zhengdong
authors.initials: Z
authors.lastname: Liu
authors.forename: Chaoliang
authors.initials: C
authors.lastname: Tan
authors.forename: Ying
authors.initials: Y
authors.lastname: Huang
authors.forename: Bing
authors.initials: B
authors.lastname: Li
authors.forename: Meiting
authors.initials: M
authors.lastname: Zhao
authors.forename: Linghai
authors.initials: L
authors.lastname: Xie
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
keywords: memory devices; nanodots; quantum dots; transition metal dichalkogenides; two-dimensional materials