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The newly emerged 2D materials heterostructures, including layered and nonlayered structures, are regarded as the building blocks for future high performance optoelectronic devices. However, it still remains a great challenge to directly synthesize 2D heterostructures for realizing broadband detection in photodetectors. In this work, the growth of vertically stacked inorganic molecular Sb2O3/monolayer MoS2 heterostructures through a two‐step chemical vapor deposition method is demonstrated, and high performance ultraviolet/near‐infrared photodetectors based on the achieved heterostructures are further developed. Excellent responsivity of 5.3 × 104 A W−1 and detectivity of 2.0 × 1015 Jones are obtained under 457 nm illumination. Additionally, the photodetection range can be extended to near‐infrared region. Maximum responsivity of 7.8 A W−1, detectivity of 3.4 × 1011 Jones, and fast response speed (<60 ms) are obtained under 1064 nm laser illumination at room temperature, which is far superior to those of the previously reported ultra‐thin 2D van de Waals heterostructures. The inorganic molecular Sb2O3/monolayer MoS2 heterostructures enrich the family of 2D materials heterostructures, showing potential applications in high performance functional electronics and optoelectronics. [ABSTRACT FROM AUTHOR]

2D heterostructures combining different layered semiconductors have received great interest due to their intriguing electrical and optical properties. However, the arbitrary growth of layers in a lateral heterostructure remains a challenge. Here, the synthesis of large‐scale lateral bilayer (LBL) WS2–MoS2 heterostructures is reported by a two‐step chemical vapor deposition route. Raman, photoluminescence, and second‐harmonic generation images show the sharp boundaries between WS2 and MoS2 domains in the heterostructure. Atomically resolved scanning transmission electron microscopy further reveals that sharp boundaries are formed by seamless connections via a lateral zigzag epitaxy between WS2 and MoS2. Notably, the photodetector device based on the LBL WS2–MoS2 heterostructure exhibits ultrahigh photoresponsivity and detectivity (6.72 × 103 A W−1 and 3.09 × 1013 Jones for 457 nm laser light, respectively), orders of magnitude higher than those of MoS2 and WS2 monocrystals. These excellent performances render LBL WS2–MoS2 heterostructures as promising candidates for next‐generation optoelectronics. [ABSTRACT FROM AUTHOR]

WS2 monolayer crystals have been grown in a large scale by chemical vapor deposition on SiO2 (300 nm)/Si substrates, and via high‐temperature treatment under protection of Ar or N2 gas flow after growth, huge amount of monolayer WS2 bubbles have been successfully created in a shape of spherical cap and widely distributed sizes. Optical and fluorescence images reveal obvious interference rings on the monolayer WS2 bubbles of large sizes. In line scans and mapping images of photoluminescence (PL) and Raman, oscillatory behaviors have been observed not only for peak intensity but also for peak position and width. It is easy to understand that the oscillatory PL and Raman peak intensities originate from constructive and destructive interference on the bubble's surface, while the oscillatory peak positions and widths are induced by the corresponding enhanced and lowered local heating effects owing to constructive and destructive interference. This is further verified by the absence of oscillation in the position and width when a heat sink layer is applied. [ABSTRACT FROM AUTHOR]