Controlled Growth of 3R Phase Tantalum Diselenide and Its Enhanced Superconductivity

• Published in: Journal of the American Chemical Society Vol. 142; no. 6; pp. 2948 - 2955
• Main Authors: Deng, Ya, Lai, Yuanming, Zhao, Xiaoxu, Wang, Xiaowei, Zhu, Chao, Huang, Ke, Zhou, Jiadong, Zeng, Qingsheng, Duan, Ruihuan, Fu, Qundong, Kang, Lixing, Liu, Yang, Pennycook, Stephen J, Wang, X. Renshaw, Liu, Zheng
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 12.02.2020
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.9b11673

Transition metal dichalcogenides (TMDs) have become a playground for exploring rich physical phenomena like superconductivity and charge-density-waves (CDW). Here, we report the synthesis of the atom-thin TaSe2 with a rare 3R phase and enhanced superconductivity. The 3R phase is achieved by an ambient pressure chemical vapor deposition (CVD) strategy and confirmed by the high-resolution aberration-corrected STEM. Low-temperature transport data reveal an enhanced superconducting transition temperature (T c) of 1.6 K in the 3R-TaSe2, which undoubtedly breaks the traditional perception of TaSe2 crystal as a material with T c close to 0 K. This work demonstrates the strength of ambient pressure CVD in the exploration of crystal polymorphism, highlights a decisive role of layer stacking order in the superconducting transition, and provides fresh insights on manipulating crystal structures to gain access to enhanced T c.