Enhancing Photodetection Ability of MoS<sub>2</sub> Nanoscrolls via Interface Engineering
Jun Su, Xin Li, Minxuan Xu, Jian Zhang, Xiaolian Liu, Xin Zheng, Yueqin Shi, Qi Zhang
Abstract
Van der Waals semiconductors have been really confirmed in two-dimensional (2D) layered systems beyond the traditional limits of lattice-matching requirements. The extension of this concept to the 1D atomic level may generate intriguing physical functionalities due to its non-covalent bonding surface. However, whether the curvature of the lattice in such rolled-up structures affects their optoelectronic features or the performance of devices established on them remains an open question. Here, MoS 2 -based nanoscrolls were obtained by virtue of an alkaline solution-assisted method and the 0D/1D (BaTiO 3 /MoS 2 ) strategy to tune their optoelectronic properties and improve the light sensing performance was explored. The capillary force generated by a drop of NaHCO 3 solution could drive the delamination of nanosheets from the underlying substrate and a spontaneous rolling-up process. The package of BaTiO 3 particles in MoS 2 nanoscrolls has been evident by TEM image, and the optical characterizations were mirrored via micro-Raman spectroscopy and photoluminescence. These bare MoS 2 nanoscrolls reveal a reduced photoresponse compared to the plane structures due to the curvature of the lattice. However, such BaTiO 3 /MoS 2 nanoscrolls exhibit a significantly improved photodetection ( R hybrid = 73.9 A/W vs R only = 1.1 A/W and R 2D = 1.5 A/W at 470 nm, 0.58 mW·cm –2 ), potentially due to the carrier extraction/injection occurring between BaTiO 3 and MoS 2 . This study thereby provides an insight into 1D van der Waals material community and demonstrates a general approach to fabricate high-performance 1D van der Waals optoelectronic devices.