Affiliation:
1. State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing 100084 China
2. Department of Materials Science and Engineering Southern University of Science and Technology Shenzhen 518055 China
Abstract
AbstractThe study of VO2 flourishes due to its rich competing phases induced by slight stoichiometry variations. However, the vague mechanism of stoichiometry manipulation makes the precise phase engineering of VO2 still challenging. Here, stoichiometry manipulation of single‐crystal VO2 beams in liquid‐assisted growth is systematically studied. Contrary to previous experience, oxygen‐rich VO2 phases are abnormally synthesized under a reduced oxygen concentration, revealing the important function of liquid V2O5 precursor: It submerges VO2 crystals and stabilizes their stoichiometric phase (M1) by isolating them from the reactive atmosphere, while the uncovered crystals are oxidized by the growth atmosphere. By varying the thickness of liquid V2O5 precursor and thus the exposure time of VO2 to the atmosphere, various VO2 phases (M1, T, and M2) can be selectively stabilized. Furthermore, this liquid precursor‐guided growth can be used to spatially manages multiphase structures in single VO2 beams, enriching their deformation modes for actuation applications.
Funder
National Key Research and Development Program of China
National Natural Science Foundation of China