KCl acts as a flux to assist the growth of sub-millimeter-scale metallic 2D non-layered molybdenum dioxide
Journal article, 2025
Two-dimensional (2D) metal oxides (2DMOs), such as MoO2, have made impressive strides in recent years, and their applicability in a number of fields such as electronic devices, optoelectronic devices and lasers has been demonstrated. However, 2DMOs present challenges in their synthesis using conventional methods due to their non-van der Waals nature. We report that KCl acts as a flux to prepare large-area 2DMOs with sub-millimeter scale. We systematically investigate the effects of temperature, homogeneous time and cooling rate on the products in the flux method, demonstrating that in this reaction a saturated homogenous solution is obtained upon the melting of the salt and precursor. Afterward, the cooling rate was adjusted to regulate the thickness of the target crystals, leading to the precipitation of 2D non-layered material from the supersaturated solution; by applying this method, the highly crystalline non-layered 2D MoO2 flakes with so far the largest lateral size of up to sub-millimeter scale (~ 464 μm) were yielded. Electrical studies have revealed that the 2D MoO2 features metallic properties, with an excellent sheet resistance as low as 99 Ω·square−1 at room temperature, and exhibits a property of charge density wave in the measurement of resistivity as a function of temperature. Graphical abstract: TOC (Table of Content) (Figure presented.)
Flux method
Metallic
Metal oxide
2D non-layered materials
Thickness modulation
Author
Liying Deng
Fujian Agriculture and Forestry University (FAFU)
Fuzhou University
Qing Zhang
Tianjin University
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
Wangyang Li
Fuzhou University
Xiao Yuan Ye
Fuzhou University
Yi Fan Zhao
Shenzhen Institute of Advanced Technology
Shen Zhong Chen
Fuzhou University
Yu Lan Wang
Fuzhou University
Xinghui Wang
Fuzhou University
Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China
Hui Peng Chen
Fuzhou University
Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China
Zhi Yang Yu
Fuzhou University
Qun Yan
Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China
Fuzhou University
Ltd.
Shu Ying Cheng
Fuzhou University
Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China
Tailiang Guo
Fuzhou University
Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China
Wen Ping Hu
Tianjin University
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
Feng Ding
Ulsan National Institute of Science and Technology (UNIST)
Institute for Basic Science
Jie Sun
Fuzhou University
Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Rare Metals
1001-0521 (ISSN) 18677185 (eISSN)
Vol. 44 1 404-416Subject Categories (SSIF 2011)
Materials Chemistry
Condensed Matter Physics
DOI
10.1007/s12598-024-02898-0