Enhancing Photodetection Ability of MoS 2 Nanoscrolls via Interface Engineering.

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.