Tungsten Ditelluride: Synthesis, Structure, and Magnetoresistance Property

Abstract

AbstractTungsten ditelluride (WTe2) is arising as an attractive material in magnetoresistance (MR) properties filed. The magnetoresistance properties of WTe2 makes it an ideal material for its magnetoresistive heads of computer and magnetic sensor device applications. So far, people have developed various controlled synthesis methods to produce large‐quantity uniform flat WTe2 crystals. Nevertheless, none of the methods are sustainable, some methods use reducing gases, and some use very long heat preservation, and the process is very complicated. Here, a mild and fast self‐flux method is described for WTe2 synthesis that can avoid producing reducing gases. After conducting structural and physical tests, it is found that annealing time is critical for WTe2 structure formation. Long annealing time improves the crystallinity of WTe2 and makes its texture more obvious, increasing the conductivity of WTe2. Therefore, it will lead to the anomalous nonsaturating positive magnetoresistance with different field dependent behaviors, reaching the ultrastrong magnetoresistive value of 1040% at 5 K and 14 T. The results provide a sustainable approach for uniform WTe2 crystal synthesis, which will benefit the large‐quantity production of WTe2 magnetoresistive materials.