Air-Stable, Large-Area 2D Metals and Semiconductors

Abstract

materials are popular for fundamental physics study and technological applications in next-generation electronics, spintronics, and optoelectronic devices due to a wide range of intriguing physical and chemical properties. Recently, the family of 2D metals and 2D semiconductors has been expanding rapidly because they offer properties once unknown to us. One of the challenges to fully access their properties is poor stability in ambient conditions. In the first half of this Review, we briefly summarize common methods of preparing 2D metals and highlight some recent approaches for making air-stable 2D metals. Additionally, we introduce the physicochemical properties of some air-stable 2D metals recently explored. The second half discusses the air stability and oxidation mechanisms of 2D transition metal dichalcogenides and some elemental 2D semiconductors. Their air stability can be enhanced by optimizing growth temperature, substrates, and precursors during 2D material growth to improve material quality, which will be discussed. Other methods, including doping, postgrowth annealing, and encapsulation of insulators that can suppress defects and isolate the encapsulated samples from the ambient environment, will be reviewed.

High-Speed Self-Powered PdSe2/Si 2D-3D PIN-like Photodetector with Broadband Response Based on PdSe2 Quantum Island Structure

“…This bizarre structure gives PdSe 2 some special properties, such as excellent mechanical flexibility, superior electrical conductivity, and unique optical properties, exhibiting great potential in the field of flexible electronics and optoelectronics. The PdSe 2 not only has excellent air stability but also has a higher mobility than some other 2D materials. − In addition, its band gap can alter from 1.3 eV in a single layer to 0 eV in bulk . This special property triggers extensive research in broad-spectrum PD.…”