Two-dimensional (2D) transition metal dichalcogenides (TMDs) semiconductors are considered to be promising candidates for extending Moore's law. 2D TMDs with tunable wrinkled nanostructures can effectively modulate their optoelectronic properties. However, the controlled synthesis of large-area TMDs wrinkled nanostructures remains a major challenge. In this work, 2D WSe2 wrinkled nanostructures were prepared on soda-lime glass substrate by ambient pressure chemical vapor deposition based on the thermal mismatch-induced strategy. WSe2 wrinkled nanostructures can be further precisely controlled by adjusting the growth temperature and substrate thickness. In addition, the growth mechanism of WSe2 wrinkled nanostructures was revealed according to systematic experimental characterization. Corresponding results indicate that the photoluminescence and surface potential of WSe2 were associated with wrinkled nanostructures. The controllable synthesis strategy of 2D WSe2 wrinkled nanostructures has been developed, which can provide important experimental and theoretical support for exploring the applications of 2D wrinkled nanostructures in the field of strain sensing, optoelectronics, and nonlinear optical devices.
Few-layer black phosphorus (BP) holds significant potential for next-generation electronics due to its tunable bandgap and high carrier mobility. The layer modulation of BP is essential in the applications of electronic devices ascribed to its thickness-dependent electronic properties. However, precisely controlling its thickness still presents a challenge for optimizing performance. In this study, we demonstrate that BP can be precisely thinned when exposed to dry oxygen (40% humidity, low oxygen concentration) in a dark environment, which is different from that exposed to humid oxygen (100% humidity, low oxygen concentration) without light illumination. The thinned BP not only demonstrates enhanced stability but also exhibits significant improvements in its electrical properties. The variation in bandgap from 0.3 to 2 eV, resulting in the ION/IOFF ratio increased from 103 to 106, and the hole mobility improved from 235 cm2 V−1 s−1 to 851 cm2 V−1 s−1, was ascribed to the layer-by-layer thinning and p-type doping effects induced by the formed PxOy. Our finding demonstrates significant potential of BP in future nanoelectronic and optoelectronic applications.
Janus transition metal dichalcogenides (TMDCs) exhibit exceptional potential for advancing applications in the fields of optoelectronics, spintronics, and valleytronics, owing to their broken structural symmetry and unique properties. However, the controlled synthesis of large-area, homogeneous monolayer Janus MoSSe remains a significant challenge due to the high activation energy barriers of chalcogen atom substitution and the complexity of conventional fabrication methods. Here, we demonstrate a one-step, two-stage chemical vapor deposition strategy enabling precise synthesis of large-area monolayer Janus MoSSe nanostructures. The preparation of Janus MoSSe in our system proceeds through the top-layer S–Se substitution mechanism, while the interfacial strain introduced by softened soda-lime glass weakens Mo–S bonds and lowers the activation barrier, thereby enabling this substitution to occur without plasma assistance. First-principles calculations reveal that increasing interfacial strain monotonically reduces the formation energy of Janus MoSSe, highlighting its critical role in directing the selective chalcogen exchange. Our work presents a scalable and controllable technique for synthesizing Janus TMDCs, which is a critical step toward practical implementation in photodetectors, solar cells, and spintronic devices.