Substrates and interlayer coupling effects on Mo_1−xW_xSe₂ alloys

Abstract

Two-dimensional (2D) transition metal dichalcogenides alloys are potential materials in the application of photodetectors over a wide spectral range due to their composition-dependent bandgaps. The study of bandgap engineering is important for the application of 2D materials in devices. Here, we grow the Mo1−x W x Se2 alloys on mica, sapphire and SiO2/Si substrates by chemical vapor deposition (CVD) method. Mo1−x W x Se2 alloys are grown on the mica substrates by CVD method for the first time. Photoluminescence (PL) spectroscopy is used to investigate the effects of substrates and interlayer coupling force on the optical bandgaps of as-grown Mo1−x W x Se2 alloys. We find that the substrates used in this work have an ignorable effect on the optical bandgaps of as-grown Mo1−x W x Se2. The interlayer coupling effect on the optical bandgaps of as-grown Mo1−x W x Se2 is larger than the substrates effect. These findings provide a new way for the future study of the growth and physical properties of 2D alloy materials.

CVD-Grown 2D Nonlayered NiSe as a Broadband Photodetector

“…Two-dimensional (2D) materials have broad application prospects in the fields of nanoelectronics, optoelectronics, and energy conversion and storage due to their unique physical and chemical properties, such as atomic-scale thickness and ideal bandgap structures [1][2][3][4][5][6][7][8][9][10]. Within them, 2D layered materials have been the most widely studied in recent years owing to the in-plane atoms bonded by strong covalent or ionic bonds and interlayers bonded by weak van der Waals forces, and their smooth surface without chemical dangling bonds, exhibiting excellent electrical, optical and mechanical properties [11][12][13][14]. Ultrathin 2D layered materials are easy to obtain and bandgaps are easy to control benefiting from the unique structure of weak van der Waals forces bonded in interlayers, resulting in great application potential in microelectronics and optoelectronics fields [8,[15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30].…”

About the selectivity and reactivity of active nickel electrodes in C–C coupling reactions

“…[24][25][26][27][28][29] In addition, nickel phosphides and other nickel salt coatings have been described as electrocatalytically active systems. [30][31][32][33][34][35] During this work we observed a distinct inuence of mechanical stirring on the formation of either homo-or crosscoupling products, which we attribute to the interaction of the vortex motion and the electrode double layer as described by Huang et al 36 In the absence of stirring, local substrate concentration is high and facilitates dimerization, whereas cross-coupling is enhanced due to charge distribution in stirred electrolytes.…”

2D Layered Material Alloys: Synthesis and Application in Electronic and Optoelectronic Devices

“…Similarly, Kang et al successfully synthesized ReS 2(1−x) Se 2x monolayers with a lateral size up to 200 μm through a salt-assisted confined-space CVD approach. [145] Third, CVD growth is generally performed under high temperature, which is normally higher than 900 K. [130,[146][147][148] This makes it suffer from a considerably large thermal budget and low degree of compatibility with the commercially available flexible substrates such as polymide, polydimethylsiloxane and polyethylene terephthalate, which is the precondition for top-surface integration. This severely hampers the development of CVD for the construction of wearable devices.…”