Thickness dependent mechanical properties of soft ferromagnetic two-dimensional CoTe2

Surbhi Slathia; Cencen Wei; Manoj Tripathi; Raphael Tromer; Solomon Demiss Negedu; Conor Boland; Suman Sarkar; Douglas S. Galvao; Alan Dalton; Chandra Sekhar Tiwary

arXiv · 2311.08994

Thickness dependent mechanical properties of soft ferromagnetic two-dimensional CoTe2

Surbhi Slathia·Cencen Wei·Manoj Tripathi·Raphael Tromer·Solomon Demiss Negedu·Conor Boland·Suman Sarkar·Douglas S. Galvao·Alan Dalton·Chandra Sekhar Tiwary

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Abstract

Two dimensional (2D) layered transition-metal-based tellurides (chalcogens) are known to harness their surface atoms characteristics to enhance topographical activities for energy conversion, storage, and magnetic applications. High surface energy due to unsaturated dangling bonds and larger lateral size than the thickness (volume) makes them a potential candidate for emerging electronics. Nevertheless, the gradual stacking of each sheet alters the surface atoms' subtle features, such as lattice expansion, leading to several phenomena and rendering tunable properties. In the present work, we have monitored thickness-dependent properties of the 2D CoTe2 sheets from nanoscale mechanics, tribology, surface potential distributions, interfacial interaction and magnetism using atomically resolved spectroscopy and different surface probe techniques, in conjunction with theoretical investigations: density functional theory (DFT) and molecular dynamics (MD). The variation in properties observed in theoretical investigation unleashes the crucial role of crystal planes of the CoTe2. The presented results are beneficial in expanding the use of 2D telluride family in flexible electronics, piezo sensors, tribo-generator, and next-generation memory devices.

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Surbhi Slathia, Cencen Wei, Manoj Tripathi, Raphael Tromer, Solomon Demiss Negedu, Conor Boland, Suman Sarkar, Douglas S. Galvao, Alan Dalton, Chandra Sekhar Tiwary. 2023-11-15. Thickness dependent mechanical properties of soft ferromagnetic two-dimensional CoTe2. https://arxiv.org/abs/2311.08994

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