A first-principles study on the electronic, piezoelectric, and optical properties and strain-dependent carrier mobility of Janus TiXY (X ≠ Y, X/Y = Cl, Br, I) monolayers

Abstract

Janus transition metal dichalcogenide monolayers (TMDs) have attracted wide attention due to their unique physical and chemical properties since the successful synthesis of the MoSSe monolayer. However, the related studies...

Symmetry-breaking-induced ferroelectric HfSnX3 monolayers and their tunable Janus structures: promising candidates for photocatalysts and nanoelectronics

“…22 The DF of FP HfSnX 3 monolayers is much larger than that of most other 2D materials. [44][45][46][47] Such a large DF is not only conducive to the separation of carriers in the photocatalytic process, but can also greatly affect the oxidation reduction potential of water. Then, the band arrangements versus redox potentials of water at different pH values of FP HfSnX 3 monolayers are performed in Fig.…”

Accelerated design for magnetic high entropy alloys using data-driven multi-objective optimization

“…The calculated parameters, including DH mix , DS mix , O and d R , of the selected alloying compositions agreed with the parametric prediction methods of the solid solution. 46,47 The calculated VEC of the alloying compositions was all between 6.87 and 8.00, which suggests mixed BCC and FCC phases according to the parametric prediction methods. 48 However, only peaks indicating the BCC phase can be clearly identified in the XRD patterns, indicating that the dominant phase among the six specimens is BCC.…”

“…According to the parametric criteria proposed in previous works, the solidsolution phase will be easily formed when À22 r DH mix r 7 kJ mol À1 and 11 r DS mix r 19.5 J K À1 mol À1 or O 4 1.1 and d R r 6.6%. 46,47 In addition, a single BCC or FCC structure was suggested to be stable at VEC Z 8 and VEC r 6.87, respectively. 48 The related parameters of the alloying compositions chosen for experimental validation are listed in Table 1.…”

Nanoprecipitate‐Strengthened High‐Entropy Alloys

“…, where r i is the atomic radius of the nth element, c i is the atomic percentage of the nth element, and r = ∑ n i=1 c i r i is the average atomic radius). [171,172] Ω infinitely close to the threshold of 1.1 may lead to the formation of secondary precipitates. [135] Therefore, according to this concept, the Fe 25 Co 25 Ni 25 Al 10 Ti 15 HEA with Ω = 1.119 and 𝛿 = 6.277 was designed.…”

“…In addition, this HEA also satisfies the empirical conditions of Ω ≥ 1.1 and δ ≤ 6.6%, where Ω is an index that weighs the stability of multi‐component solid solutions (, [ 135 ] where T m is the liquidus temperature of alloys, Δ S mix is the entropy of mixing, and Δ H mix is the enthalpy of mixing), and δ represents the difference in the atomic sizes between constituent elements , where r i is the atomic radius of the nth element, c i is the atomic percentage of the nth element, and is the average atomic radius). [ 171,172 ] Ω infinitely close to the threshold of 1.1 may lead to the formation of secondary precipitates. [ 135 ] Therefore, according to this concept, the Fe 25 Co 25 Ni 25 Al 10 Ti 15 HEA with Ω = 1.119 and δ = 6.277 was designed.…”