Energy Harvesting from Atomically Thin Co₂Te₃

Abstract

Two-dimensional (2D) materials have received a surge in research interest due to their exciting range of properties. Here, we show that 2D cobalt telluride (Co2Te3), successfully synthesized via liquid-phase exfoliation in an organic solvent, exhibits weak ferromagnetism behavior at room temperature. Under a small amount of mechanical pressure, the material shows an electrical signal. Here, we also study the effect of the magnetic field on strain generation in the atomically thin Co2Te3 material and observe a linear relationship between the output voltage and the applied magnetic field. First-principles density functional theory (DFT) and ab initio molecular dynamics are used to explain these experimental results. Our work could pave the way for the development of 2D materials with coupled magnetism and flexoelectricity, leading to new applications in magnetic field sensing.

Hinge-like Co2S3and Co2Te3Nanosheets: Promising Two-Dimensional Optical, Thermoelectric, and Spintronic Materials

“…The maximum MAE for 2D Co 2 S 3 (26.6 μeV) and 2D Co 2 Te 3 (2.62 meV) occurs at ϕ = 90 where the spin rotation is parallel to the xy plane and the MAE is independent of the azimuthal angle. The anisotropy energy of the Co 2 Te 3 nanosheet is higher than some 2D materials, including CrI 3 , Cr 2 O 3 , Cr 2 S 2 , Cr 2 Ge 2 Te 6 , and Co 2 Te 3 (rhombohedral structure). ,, As a result, 2D Co 2 Te 3 has a significant intrinsic ferromagnetic stability, which makes it a candidate for magnetoelectronic and spintronic nanodevices.…”

“…The MAE of the Co 2 X 3 (X = S, Te) nanosheets as a function of the polar angle (ϕ) calculated with the DFT + U method is shown in Figure 3, where the azimuthal angle (θ) is zero and MAE at ϕ = 0 is considered as zero. 16,20,68 As a result, 2D Co 2 Te 3 has a significant intrinsic ferromagnetic stability, which makes it a candidate for magnetoelectronic and spintronic nanodevices.…”

“…Negedu et al successfully synthesized 2D CoTe, CoTe 2 , and Co 2 Te 3 layers using the liquid-phase exfoliation method. They showed that these structures are ferromagnetic semiconductor, antiferromagnetic metal, and weak ferromagnetic semiconductor, respectively, and among them 2D CoTe was introduced as a suitable candidate for spintronics. − Thermoelectric materials are one of the most environment-friendly materials as they directly convert waste heat into electricity, and the efficiency of these materials is expressed by the dimensionless coefficient ZT . According to the studies, when the dimensions of the material are reduced to the nanoscale, the ZT value increases because of the quantum limitation and its effect on the dimension-dependent properties. , So far, various groups have investigated the thermoelectric properties of 2D TMCs.…”

Emerging 2D Cobalt Telluride (CoxTey): from Theory to Applications

“…Figure 3a shows the current-voltage (I-V) curves of CoTe fieldeffect transistor from 5 to 300 K. The nonlinear I-V curves exhibit reduced current density at lower temperature. A negative gate voltage (Figure 3b) increases the channel current, suggesting the p-type semiconductor of CoTe nanostructure prepared from the [ 32] 1: semiconducting (nano-size or quantum dot) [ 96] ; 2: metallic, 1.8×10 6 S/m (film) [98] 1: semiconducting [34] ; 2: metallic [ 76] nonmetallic [ 57] saturation magnetization 37.38 emu/g [33] 0.38 emu [ 58] weak ferromagnetism [34,76] ∼10 emu/g [ 57] 7.52 emu/g [ 81] paramagnetic [ 58,83] 13.4 emu/g [ 83] others 1: low overpotential [ 16] ; 2: ferrimagnetic [ 81] 1: Dirac fermiology [ 24] ; 2: temperature-dependent emission [ 30] ;…”

Fingerprint Raman spectroscopy for two-dimensional MoS2x Se2(1−x) alloys

“…Two-dimensional transition metal chalcogenides are widely used for as the basis for the fabrication of various optoelectronic nanostructures due to their unique physical properties [1]. In particular, direct-bandgap [2], high mobility of charge carriers [3], large on-off ratio in field effect transistors [4] makes it possible to use semiconducting transition metal dichalcogenides (TMDs) for creating photodetectors [5,6], phototransistors [7], solar cells [8,9], and other devices.…”