Physical vapor deposition and enhancement of optoelectronic properties of SnSe2 platelets

Visible-to-near-infrared photodetectors based on SnS/SnSe2 and SnSe/SnSe2 p−n heterostructures with a fast response speed and high normalized detectivity

“…As a nascent member of 2D materials, tin diselenide (SnSe 2 ) is an instinct n-type Ⅳ−Ⅵ semiconductor with a Se−Sn−Se sandwich-layered structure and a bandgap of ~1 eV [4] . Furthermore, with its exceptional qualities of high carrier mobility (462 cm 2 /(V• s)) [5] , absorption coefficient (7.25 × 10 5 cm −1 ) [6] , environmental friendliness [7] , and chemical stability [8] , SnSe 2 is a superior material for high-sensitivity and lowconsumption photodetectors, which can be widely used in image acquisition [9] , information communication [10] , and photo-electronic memory [11] . For example, Chen et al fabricated a SnSe 2 -based photodetector via low-temperature molecular beam epitaxy, which demonstrated a normalized detectivity of 6.09 × 10 9 cm•Hz 1/2 •W −1 under 532 nm illumination [12] .…”

Gradient Cr–AlN composite coating prepared on alumina-forming austenitic steel

“…Many previous studies [11][12][13] have shown that one of the most effective ways to enhance wear resistance and surface hardness is by coating it. Coating technology can be broadly categorised into two groups: one is thermal diffusion type, including gas diffusion infiltration, hot dip coating, packcementation, 13 and high-energy beam surface treatment 14,15 ; the other is deposition type, including physical vapour deposition, [16][17][18][19] chemical vapour deposition, [20][21][22] electroplating, 23,24 spraying, 25,26 micro-arc oxidation, 27,28 etc. Pack-cementation is an efficient, simple, mature, and low-cost approach for preparing metallic and ceramic coatings on metals and alloys.…”