Molybdenum disulfide (MoS2) is a promising 2D semiconductor material for its unique characteristics such as tunable bandgap, high electrical conductivity, and strong light–matter interaction. Presently, many efforts have been made to modulate its properties, such as surface engineering, strain introduction, doping, and so on. Recently, it has been proved that substitutional metal doping is an effective approach to tune the energy bandgap of the aimed material and improve the performance of the device. Conventional metal doping methods will inevitably introduce impurities or defects and cannot control doping regions. Ion implantation is widely used in traditional semiconductor modification processes due to its high efficiency, controllability, and homogeneity. But it is rarely applied to 2D materials because of the damage caused during the implantation process. Here, the SiO2 substrate is implanted by tungsten ion implantation and then the tungsten doping of MoS2 is successfully achieved by chemical vapor deposition (CVD) growth process, while avoiding direct implantation damage to it. The W‐doped MoS2 photodetectors show a high‐speed response with a rise/fall time of 210 ms/160 ms. This work provides a novel doping strategy for metal doping of 2D materials and opens a new avenue to modify 2D materials properties.

In recent years, two-dimensional (2D) layered metal dichalcogenides (MDCs) have received enormous attention on account of their excellent optoelectronic properties. Especially, various MDCs can be constructed into vertical/lateral heterostructures with many novel optical and electrical properties, exhibiting great potential for the application in photodetectors. Therefore, the batch production of 2D MDCs and their heterostructures is crucial for the practical application. Recently, the vapour phase methods have been proved to be dependable for growing large-scale MDCs and related heterostructures with high quality. In this paper, we summarize the latest progress about the synthesis of 2D MDCs and their heterostructures by vapour phase methods. Particular focus is paid to the control of influence factors during the vapour phase growth process. Furthermore, the application of MDCs and their heterostructures in photodetectors with outstanding performance is also outlined. Finally, the challenges and prospects for the future application are presented.

Engineering materials for nuclear reactors exposed to high-dose irradiation breed various radiation damage, leading to performance degradation of materials, which seriously limits the application of materials in the future advanced nuclear reactors. Tungsten-based materials applied in future nuclear reactors have to withstand not only the attack of high-energy neutron and plasma, but also the repeated impact of steady-state or even transient thermal load. Researches in the past decades have proved that tailored nanostructure have advantage in annihilating radiation defects. With the rapid development of nanostructured tungsten, probing radiation application of nanostructured tungsten is of great significance in promoting the development of novel radiation-resistant materials. Herein, the development status of three kinds of nanostructured tungsten namely nanocrystalline, nanofilm and nanoporous tungsten designed for radiation tolerance and the performance enhancement mechanism of diverse nanostructure in irradiation environment is reviewed. Finally, future perspectives and technical challenges are discussed, to inspire more creative designs of novel nanostructured tungsten for radiation tolerance.

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The 2D GeSe‐based photodetectors have exhibited ultrahigh photoresponsivity (Rλ), sensitive‐specific detectivity (D*), and large external quantum efficiency (EQE) in previous researches. Ion beam techniques have been utilized to effectively modify the surface of nanomaterials for recent years. Herein, the authors propose to engineer the 2D GeSe nanosheets via low‐energy ion irradiation for improving the photoresponse in visible region. The nonmetallic nitrogen and metallic silver elements are selected to modulate the performance of 2D GeSe FETs, respectively. The results show that N‐irradiated GeSe nanosheets have exhibited twice faster photoresponse for 532 nm laser for making up the trailing phenomenon in the decay process during the dynamic response of pristine 2D GeSe. More importantly, via Ag ion irradiation, a self‐driven and higher photoresponsivity GeSe‐based photodetector is realized. The Ag‐irradiated GeSe nanosheets have shown the considerably high Rλ of 9.6 × 102 A W−1 with no bias and no gate voltage applied. The work provides a new direction for modification of other 2D materials by ion beam technique for optoelectronic devices.

Nonvolatile flash memory is an important component of the semiconductor memory device, which is widely used in a variety of portable electronic equipment. As traditional flash memory approaches its physical limit, reduced reliability and performance degradation have become unavoidable. Two-dimensional (2D) layered materials exhibit excellent electronic properties even at the atomic level and have been considered as a promising development direction for future flash memory. Here, we report a MoS2-based Ag nanocrystal memory. The fabricated memory device can form the memory stack in one step through metal ion implantation, omitting tedious deposition steps compared to the conventional process. The fabricated silver nanocrystal memory exhibits a 9 V memory window and a high ON/OFF current ratio (>107). In addition, the device also exhibits good endurance characteristics of more than 104 cycles. The ion implantation technology and the 2D nature of the channel can be used for the fabrication of flexible nanoelectronic memory devices with large-scale integration.