Transformation of CrSe Monolayers into Room-Temperature Half Metals via Chemical Edge Modification

Abstract

The pristine 2D CrSe monolayer possesses obvious ferromagnetic (FM) metal properties at temperatures below 280 K. Some chemical groups, such as F, H, and O, are unavoidably adsorbed on the surfaces of the 2D materials in the chemical vapor depositiongrown process. In this work, we systematically study the electronic and magnetic properties of 2D CrSe monolayer derivations by first principles calculation. This indicates that CrSe monolayer derivations are transformed into FM half metals when Cr1 atoms are unilaterally saturated with F, H, and O chemical groups. Meanwhile, both of the surfaces are saturated with chemical groups (i.e., −H and −O), and the FM half metal character is also maintained in this case. More importantly, the Curie temperature of the CrSe monolayer derivations is enhanced to as high as ∼530 K by Monte Carlo simulations. Thus, our results show that the CrSe derivation monolayers have great potential application in the spintronics industry.

Room-temperature antiferromagnetic CrSe monolayer with tunable metal–insulator transition in ferroelectric heterostructures

“…It is worth noting that the P3m1 phase reported in Ref. [13] is actually a metastable phase. Here, we investigate the thermodynamic stability of the P4/nmm phase which is the groundstate structure of CrSe ML.…”

“…To explore 2D TMCs with Cr, Zhang et al synthesized a quasi-2D ferromagnetic (FM) CrSe film with a thickness of approximately 2.5 nm and a Curie temperature of 280 K [12]. Intriguingly, first-principles calculations reveal that this layered structure can be transformed from a FM metal to a room-temperature half-metal via chemical edge modification [13]. Besides, a pentagonal AFM CrSe ML is proposed by utilizing atomic transmutation from pentagonal building blocks [14].…”

“…shows the total energies of all the structures discovered in this study and those reported in literatures, including the P3m1 phase in Refs. [13,29], the P4/m phase in Ref. [14] and the P-3m1…”

Room-temperature half-metals induced via chemical surface modification: 2D Mn2Se2 monolayer

“…The T c of CrSe monolayer derivatives increases beyond room temperature (about 530 K). 33 Therefore, chemical surface modification can be a great way to change the electromagnetic features of 2D materials. Compared with the low T c of 2D FM semiconductors, AFM semiconductors have much higher ordering temperatures, which allows easy control of the magnetic behavior.…”

Giant tunneling electroresistance in a 2D bilayer-In2Se3-based out-of-plane ferroelectric tunnel junction

“…Together with the rise and intensive study of two-dimensional (2D) materials, [17][18][19][20][21][22][23] 2D ferroelectric materials have become a new research direction of ferroelectric materials due to their atomic thickness and ideal surfaces that are free from dangling bonds and structural reconstruction. At present, many ferroelectric materials with in-plane or out-of-plane spontaneous polarization have been obtained by theoretical predictions and experimental methods.…”