Van der Waals epitaxy of CsPbBr 3 /WSe 2 heterostructure and dynamics study of exciton recombination

• Published in: Journal of physics. D, Applied physics Vol. 57; no. 23; p. 235103
• Main Authors: Chen, Meili, Chang, Ruiguang, Yang, Xinhui, Lu, Chang, Zhang, Shunhui, Zhang, Zhengwei, He, Jun, Yuan, Xiaoming
• Format: Journal Article
• Language: English
• Published: 07.06.2024
• ISSN: 0022-3727; 1361-6463
• DOI: 10.1088/1361-6463/ad30ae

Abstract Van der Waals heterostructures formed by inorganic perovskites and transition metal dichalcogenides (TMDCs) have promising applications in photonics and optoelectronics. However, there are few studies on the properties of CsPbBr 3 /TMDC at low temperatures. Here, we demonstrate van der Waals epitaxy of CsPbBr 3 nanowires (NWs), nanoplates (NPs) and nanocones (NCs) on monolayer (ML) WSe 2 , and investigate the lattice dynamics of the heterostructure at low temperatures using temperature-dependent Raman spectroscopy. In addition, temperature-dependent photoluminescence (PL) spectroscopy shows that the type II band alignment between CsPbBr 3 and ML WSe 2 leads to a broad emission peak at the low-energy side of the ML WSe 2 emission at low temperatures. Meanwhile, a high-energy peak appears near the CsPbBr 3 emission below 133 K, which may be related to the phase transition of CsPbBr 3 from the cubic to the orthorhombic phase. These findings are important for the development of van der Waals heterostructure based self-powered photodetector with high performance.