Half-metallic Behavior Research Articles

First-principles study on rare earth-based equiatomic quaternary Heusler alloys YbCoCrSb and YbCoTiSn: New candidates for spintronics

We have investigated the structural, mechanical, thermal, electronic, magnetic, and half-metallic properties of new Yb-based EQHAs such as YbCoCrSb and YbCoTiSn using first-principles calculations. We computed the ground state properties of different possible crystal structures and magnetic states. We also calculated their elastic constants and derived mechanical parameters, including bulk, shear, and Young's moduli, as well as Poisson's and Pugh ratios. The electronic structure of both EQHAs shows half-metallic behavior with a spin down band gap of 0.39 eV for YbCoCrSb and 0.30 eV for YbCoTiSn in the GGA-PBE scheme. The estimated total spin magnetic moment has a positive integer value, which is well in accordance with the Slater-Pauling rule of 18. Because of the nearly closed f orbital shell of the Yb atom, the total spin magnetic moment is mainly dependent on 3d transition metal atoms. These alloys exhibit TC > 300 K using the mean field approximation.

First-principles study of structural, electronic and magnetic properties of diluted magnetic semiconductor and superlattices based‏ on Cr-doped ZnS and ZnSe compounds in wurtzite-type crystal

We performed first-principle calculations to investigate the structural, electronic, and magnetic properties of ZnS and ZnSe binary compounds, Zn0.5Cr0.5S and Zn0.5Cr0.5Se DMS alloys and (ZnS)2/Zn0.5Cr0.5Se and (ZnSe)2/Zn0.5Cr0.5S superlattices in the wurtzite structure using the full potential linear muffin–tin orbital (FP-LMTO) method. Features such as lattice constant, modulus of compressibility and its first derivative, spin-polarized band structures, total and local or partial electronic densities of states and magnetic properties were calculated. The electronic structure shows that Zn0.5Cr0.5S and Zn0.5Cr0.5Se DMS alloys and (ZnS)2/Zn0.5Cr0.5Se and (ZnSe)2/Zn0.5Cr0.5S superlattices are half-metallic ferromagnetic with 100% complete spin polarization. The total magnetic moments calculated show the same integer value of 4 µB, which confirms the ferromagnetic half-metallic behavior of these compounds. We found that the ferromagnetic state is stabilized by the p-d exchange associated with the double-exchange mechanism. Zn0.5Cr0.5S and Zn0.5Cr0.5Se DMS alloys and (ZnS)2/Zn0.5Cr0.5Se and (ZnSe)2/Zn0.5Cr0.5S superlattices are shown to be promising new candidates for applications in the fields of spintronics.

First principle studies on half-metallicity and pressure-induced half-metallic band gap in 3-d transition metal-based quaternary Heusler ScVCoZ (Z = Si, Ge, Sn, P, As, and Sb) alloys

In the present work, we predict a series of 3-d transition metals-based quaternary Heusler alloys (QHA) ScVCoZ (Z = Si, Ge, Sn, P, As, and Sb) (SVCZ), by employing density functional theory (DFT) calculations. We carried out extensive band structure (BS) and density of states (DOS) analysis to explain the half-metallic and magnetic behavior of the alloys. We found that SVCZ alloys stabilize in the F 4̅ 3m space group and exhibit a ferromagnetic (FM) ground state (GS). Among the QHAs, SVCZ (Z = Si, Ge, and Sb) exhibit intriguing half-metallic properties featuring 100% spin polarization at the Fermi level (EF). Additionally, the effect of pressure indicates a band gap opening in one of the spin channels for SCVZ (Z = P, and As), and the half-metallic characteristics are retained up to a compressive pressure, respectively of 65, and 79 GPa for SCVP and SCVAs. Elastic properties calculations suggest SVCZ alloys satisfy Born stability criteria and are mechanically stable. Among the predicted QHAs, SVCZ (Z = Si, Ge, and Sn) shows brittle nature, whereas SVCZ (Z = P, As, and Sb) are ductile.

First-principles simulations of magnetic properties of Co- and Ni-doped ZnSe

We purposed to analyze the theoretical ab initio study of ferromagnetism and to estimate Curie temperature of Co2+ and Ni2+ 3d transition metal (TM) ions doped Zn1-x TM x Se compounds for 12.5 % and 6.25 % concentrations of impurity TM(Co, Ni) atoms. The calculations are carried out using the norm-conserving Fritz-Haber-Institute ionic pseudopotentials based on density functional theory within the local spin density approximation and Hubbard U (U(Znd)=4.5 eV; U(Sep)=3.8 eV) corrections. The analysis of the total and partial electron density of states shows the half-metallic ferromagnetic behavior with a half-metallic bandgap. The theoretically obtained total magnetic moments of TM(Co, Ni) doped Zn1-x TM x Se systems are equal to 3 μB and 4 μB, correspondingly.

Computational study of half-metallic behavior, optoelectronic and thermoelectric properties of new XAlN3 (X = K, Rb, Cs) perovskite materials

In this study, we systematically explored the properties of novel perovskite materials, XAlN3 (X = K, Rb, and Cs), based on first-principles calculations and semiclassical Boltzmann transport theory. Generalized gradient approximation and HSE06 hybrid functional methods were used to investigate the electronic band structures. Our findings indicated intriguing half-metallic behavior where the spin-down state had metallic characteristics, whereas the spin-up state behaved as an insulator for all compounds, with indirect band gaps. These compounds had a significant magnetic moment of 5 μB, which confirmed their half-metallic nature. Analysis of the elastic constants indicated distinctive mechanical properties. Moreover, the dielectric functions indicated efficient energy absorption across a broad energy spectrum, which is particularly beneficial for ultraviolet optoelectronic applications. At 300 K with a chemical potential (μ) of +1.37 eV, CsAlN3 had a notable thermoelectric figure of merit (ZT) of 0.99. This ZT value remained competitive at 0.97, even at a high temperature of 1000 K in the p-type region. However, the ZT and Seebeck coefficients decreased in a temperature-dependent manner to affect the thermoelectric characteristics of these materials. Overall, our findings suggest that XAlN3 (X = K, Rb, and Cs) perovskite materials are promising candidates for use in various applications in spintronics, optoelectronics, and thermoelectric devices.

Predictive analysis of a new FeVTe alloy from first principles: An excellent choice for thermoelectric applications

To predict the thermoelectric (TE), magnetic, and electrical properties of the novel half-Heusler FeVTe as well as its dynamical, mechanical, and structural stability, this investigation makes use of the WIEN2K code and the FP-LAPW technique, which relies on density functional theory (DFT). The exchange-correlation potential in this analysis is handled using the GGA-PBE approximation. According to our predicted results, we can draw the conclusion that this compound exhibits stability in the ferromagnetic (FM) type I phase and reveals a total magnetic moment of unity. From the computed band structure, FeVTe unveils half-metallic (HM) behaviour, showing metallic features in the spin-up direction and a semiconductor character in the downspin direction with an indirect bandgap of 1.27 eV. The alloy complies with the Slater-Pauling law based on the predicted spin-polarized magnetic moments (MMs). Also, the results obtained for the elastic constants suggest that this material is ductile, anisotropic, and mechanically stable. Moreover, this compound demonstrates a remarkable figure of merit at room temperature and elevated temperatures, suggesting its potential as promising material for thermoelectric applications.

First-principles investigation for the hydrogen storage, mechanical, electronic, optical, dynamic, and thermodynamic properties of XMnH3 (X=Na, K, Rb) perovskites for hydrogen storage applications

The perovskite-type hydrides are potential candidate materials for the hydrogen storage. On the basis of the first-principles calculations, the hydrogen storage, mechanical, electronic, optical, thermodynamic and kinetic properties of XMnH3 (X = Na, K, Rb) perovskites are investigated in this paper. The lattice constants of the optimized NaMnH3, KMnH3, and RbMnH3 are 3.59, 3.89, and 4.05 Å, respectively. The Poisson's ratio, Cauchy's pressure, and B/G consistently prove that all of the XMnH3 hydrides are brittle. The exploration of electronic properties reveals that NaMnH3 exhibits metallic behavior, while KMnH3 and RbMnH3 exhibit half-metallic behavior. According to the charge density distribution and Poisson's ratio, both ionic and covalent bonds exist in XMnH3. The Bader partial net charges are also calculated to analyze the charge transfer in XMnH3. The results of optical properties of XMnH3 show that NaMnH3 has the largest static dielectric constant and static refractive index. Based on the formation energy, Born stability criterion, and phonon dispersion curve, it is demonstrated that XMnH3 compounds have thermodynamic, mechanical, and dynamic stability. The gravimetric hydrogen storage capacities are 3.74, 3.12, and 2.11 wt% for NaMnH3, KMnH3, and RbMnH3, respectively. Above investigations suggest that NaMnH3 is the most suitable hydrogen storage material among the three compounds.

Thermodynamic, mechanical stability, and magneto-electronic features of Ti2-based quaternary Heusler alloys Ti2CoGa1−xCux (x=0, 0.25, 0.5, 0.75, and 1): A DFT investigation

In this work, we have used the full-potential linearized augmented plane wave (FP-LAPW) method implemented in the WIEN2k code combined with the generalized gradient approximation (GGA) of the density functional theory (DFT) to study the structural, elastic, mechanical, electronic, magnetic, and thermodynamic properties of the parent ternary inverse Heusler compounds based on Titanium and Cobalt Ti2CoGa, Ti2CoCu in the Hg2CuTi-type structure and their quaternary alloys Ti2CoGa[Formula: see text]Cux ([Formula: see text], 0.5, 0.75) for the chosen concentrations using a supercell with 16 atoms. We have calculated the structural properties, such as the lattice parameters, bulk modulus, and its first derivative, which are in good agreement with those that have been obtained based on other published theoretical methods. Also, we calculated the elastic constants of the studied Heusler alloys, and we found that these materials are elastically stable, ductile, and anisotropic. Therefore, the electronic and magnetic properties indicate that Ti2CoGa exhibits a half-metallic (HM) ferromagnetic behavior, while Ti2CoCu shows a metal and a non-magnetic (NM) character. Their quaternary alloys are found to be nearly HM ferromagnetic materials, with a magnetic moment mainly due to the atom Ti. Furthermore, the quasi-harmonic Debye model, which incorporates the lattice vibrations, was used to estimate the thermodynamic effects on some macroproperties of the Ti2CoGa[Formula: see text]Cux alloys. Successful results were achieved for the variations of the primitive cell volume, bulk modulus, heat capacities, and Debye temperature with pressure and temperature, respectively, in the ranges of 0–30[Formula: see text]GPa and 0–1400[Formula: see text]K. To our knowledge, no analogous investigations on the mechanical and thermodynamic properties of the Ti2CoGa[Formula: see text]Cux ([Formula: see text], 0.5 and 0.75) alloys have been performed to date. As a result, it is predicted that Ti2CoGa[Formula: see text]Cux Heusler alloys will be promising candidates for actual applications in spintronic devices.

Ab-initio calculation of magnetic properties of doped methylammonium lead chloride

ABSTRACT Magnetic properties of 3d transition metal ion doped methylammonium lead chloride (MAPbCl3) have been studied by ab-initio calculations in the framework of density functional theory. The study of spin–spin interactions reveals that doping (about 2%) of Ti, V, Cr, Mn and Fe at the Pb site of MAPbCl3 shows stable ferromagnetic ordering along with the half-metallic behaviour. 3d orbital electrons of the dopants are primarily responsible for the origin of the magnetic moment and the remaining part comes from the p-d exchange interaction between the 3d orbital electrons of the dopants and the 6p orbital electrons of Pb in the vicinity of the doping position. Additionally, the band structure calculations suggest that the doped system shows n/p-type semiconducting behaviour. Ferromagnetism, along with semiconducting behaviour in transition metal ion-doped MAPbCl3, will be suitable for spintronic applications.

Experimental realization of CoFeRuSn quaternary Heusler alloy for room temperature spintronic applications

We synthesize CoFeRuSn equiatomic quaternary Heusler alloy using arc-melt technique and investigate its structural, magnetic, and transport properties. The room temperature powder x-ray diffraction analysis reveals that CoFeRuSn crystallizes in cubic crystal structure with small amount of DO3-disorder. The field dependence of magnetization shows non-zero but small hysteresis and saturation behavior up to room temperature, indicating soft ferromagnetic nature of CoFeRuSn. The magnetic moment estimated from the magnetization data is found to be 4.15 μB/f.u., which is slightly less than the expected Slater–Pauling rule. The deviation in the value of experimentally observed moment from the theoretical value might be due to small disorder in the crystal. The low temperature fit to electrical resistivity data shows the absence of quadratic temperature dependence of resistivity, suggesting half-metallic behavior of CoFeRuSn. The high Curie temperature and possible half-metallic behavior of CoFeRuSn make it a highly promising candidate for room temperature spintronic applications.

Spin-selective transport in edge-passivated zigzag magnesium dichloride nanoribbons: Towards bipolar spin diode and spin rectification devices

In the present work, we investigate the electronic, magnetic, and spin transport properties of zigzag MgCl2 (ZMgCl2) nanoribbons with different types of edge passivation using first-principles calculations based on density functional theory and non-equilibrium Green’s function techniques. Our findings reveal that the ZMgCl2 nanoribbon with Cl edges (ClαClα) and Mg edges (MgMg) exhibits distinct properties depending on the type of passivation. Passivation with O and F on ClαClα edges transforms the nanoribbon into a magnetic semiconductor. Passivation with H and F on MgMg edges results in a semiconductor behavior, B passivation leads to a half-metal behavior, and O passivation to a magnetic semiconductor. Additionally, our transport simulations demonstrate that the ClαClα-F nanoribbon operates as a single spin filter under bias voltage. For the MgMg-B nanoribbon, the behavior varies depending on the magnetic configuration of the electrodes. In the parallel configuration, MgMg-B also functions as a single spin filter, whereas in the antiparallel configuration, it operates as a dual spin filter device. Overall, our results highlight the remarkable potential of two-dimensional MgCl2 for spintronics applications, emphasizing the influence of edge passivation on the electronic and transport properties of nanoribbons.

Manipulable ferromagnetic properties and half-metallic behavior in hole-doped PbClI monolayer: A DFT study

The remarkable performance exhibited by two-dimensional (2D) materials holds tremendous promise for transformative applications in the domains of electronics and spintronics. This study through first-principles calculations presents a systematic investigation of the novel 2D material PbClI monolayer. It is found that the PbClI monolayer exhibits desirable semiconductor properties, characterized by a large gap of 3.75 eV. Furthermore, it has been observed that mechanical strain can effectively tune this bandgap. Importantly, due to its unique flat valence band edge, hole doping in PbClI gives rise to pronounced features of ferromagnetism and half-metallicity, and hole doping levels can effectively tune its magnetic properties, including magnetic coupling strength, easy magnetization axis, and Curie temperature. In addition, PbClI monolayer shows outstanding multidirectional piezoelectricity. The calculations serve as a pivotal theoretical framework for the realization of stable magnetism in 2D materials.The study uncovers the vast possibilities in PbClI monolayer to position it as a potential candidate in the domains of spintronics and optoelectronics.

Probing electronic, magnetic and thermal properties of NiMnSb Half-Heusler alloy for spintronics as an environmentally friendly energy resource: A DFT+U and Monte Carlo study

The NiMnSb Half-Heusler alloy has a high Curie temperature (Tc = 720 K) and high spin polarization (P = 100%), which makes it one of the good magnetic materials with exceptional structural, electrical, magnetic, and thermo-elastic properties. Using Density Functional Theory with Hubbard correction and Monte Carlo methods, we have probed the electronic, magnetic and thermal properties of NiMnSb. The computational study found a lattice parameter of 5.91Å and an integer value of total moment magnetic equal to 4μB using GGA method. However, using the Hubbard correction, these values increased by 0.17% and 9.25% to the experimental results, respectively, which also resulted in the destruction of the Half-metallic behavior. The high total magnetic moment is preserved despite bulk and axial strain by varying the relative change of lattice parameter and c/a ratio. The variation of spin polarization against the change of lattice parameter to experimental value reveals a very strong spin polarization between -2.2% and 0.2%. The thermal properties show that the alloy under probing is more stable, both thermodynamically and thermo-mechanically. The Monte Carlo simulation shows that NiMnSb’s strong ferromagnetic property stays its high as the temperature rises to 720 K. Above 720 K, NiMnSb joins the group of paramagnetic materials.

Structural, electronic, magnetic and optical properties of transition metal doped boron arsenide nanosheets

Due to the fascinating properties of the BAs monolayer and its promising applications, we study the structural, electronic, magnetic, and optical properties of the 3d transition metal mono-doped BAs nanosheets using first-principle calculations. Two substitutional doping configurations are considered at sites B (dopantB) and As (dopantAs). The doped structure at site As is more stable than at site B for the same dopant because the difference in atomic size between the dopant and As atoms is smaller than the corresponding dopant and B atoms. We explain the magnetic moments of the doped monolayer in terms of the number of valence electrons, the oxidation number, and the coupling between the electrons in the outer shell of the dopant. The MnB, Cu, and ZnB dopings convert the semiconducting behavior of the pristine BAs monolayer into metallic behavior. The BAs monolayer becomes a dilute magnetic semiconductor under the influence of VB, Cr, FeB, CoB, and Ni dopings. Due to their half-metallic behavior, the Ti-, Mn-, Fe-, and Zn-doped BAs at the site As can be used in spintronic applications. The TiAs and MnAs doped BAs nanosheets can enhance light absorption in the infrared and small range of the visible light regions as compared to pristine and the other doped nanosheets. The results indicate that doped BAs monolayers can be used in various optoelectronic and spintronic applications.

Rational design of 2D Janus P3m1 M2N3 (M = Cu, Zr, and Hf) and their surface-functionalized derivatives: ferromagnetic, piezoelectric, and photocatalytic properties.

In this study, first-principles calculations were employed to rationally design two-dimensional (2D) Janus transition metal nitrides of P3m1 M2N3 phases, where M is a d-block element (Sc-Zn, Y-Cd, Hf-Hg). Among the 29 examined 2D M2N3, three 2D phases, namely P3m1 Cu2N3, Zr2N3, and Hf2N3, exhibit excellent thermodynamic, dynamic, mechanical, and thermal stabilities. These novel Janus 2D materials exhibit ferromagnetic metallic and half-metallic behavior. The related 2D Janus surface-functionalized derivatives, Cu2N3H, Cu2N3F, Cu2N3Cl, Zr2N3H, Hf2N3H, and Hf2N3F, are all dynamically stable. The 2D Janus P3m1 phases of Zr2N3H, Hf2N3H, and Hf2N3F, all with M in the +IV oxidation state, act as semiconductors in the visible region, with energy band gaps of 2.26-2.70 eV at the HSE06 level of theory. On the other hand, the 2D Janus P3m1 Cu2N3X phases (where X = H, F, and Cl) are ferromagnetic half-metals. Additionally, it has been unveiled that there are high hole mobilities (∼6 × 103 cm2 V-1 s-1) derived from the moderate deformation potential and effective mass in the 2D Janus P3m1 Zr2N3H, Hf2N3H, and Hf2N3F phases. Uniaxial strain engineering has demonstrated the outstanding in-plane piezoelectric properties of 2D Janus P3m1 Zr2N3H, Hf2N3H, and Hf2N3F with high d11 values (∼99.91 pm V-1). Furthermore, the desirable band-edge alignments and high anisotropic carrier mobilities of 2D Janus P3m1 Zr2N3H, Hf2N3H, and Hf2N3F phases indicate their potential as visible light-driven photocatalysts for water splitting reactions on different facets. These properties render 2D Janus P3m1 Zr2N3H, Hf2N3H, and Hf2N3F phases promising for use in optoelectronics, piezoelectric sensing, and photocatalysis applications.

DFT insights on the Be1-xCrxS alloys for optoelectronic and magnetic devices

In this work, the electro-optical and magnetic characteristics of Be1-xCrxS (x= 6.25%, 12.5% and 25%) are brought into investigation by employing full potential linearized augmented plane wave (FP-LAPW) scheme designed within density functional theory (DFT). The stability of the Be1-xCrxS alloy is justified by the negative values of formation energy. The band structures and density of states are examined by using GGA functional. Be1-xCrxS compound demonstrates the half-metallic (HM) ferromagnetic behavior for all doping concentrations; spin-up channel reveals the metallic character and other spin version displays the semiconductor (SC) behavior. The values of total magnetic moment (µB) are recorded as 4.0 8.0 and 16.0 µB for corresponding 6.25%, 12.5% and 25%, which mainly arises owing to Cr-3d state. Moreover, optical features including dielectric function ε(ꞷ), reflectivity, refraction, and absorption are explored within range of 0-10 eV. The maximum absorption of incident photons was found in ultraviolet (UV) span which implies their importance for optoelectronic applications. Results reveal that the studied alloy has potential applications in magnetic and optoelectronic gadgets.

Anisotropic half-metallicity in zigzag edge SiP3 nanoribbons.

We investigate magnetic and spin-transport properties of the zigzag-edge nanoribbon structures of two-dimensional (2D) SiP3 system within first-principle calculations. Based on the edge terminations, the nanoribbons can be categorized in three subclasses, two of them with even number of silicon (Si) atoms and one of them with odd number of Si atoms in the one-dimensional unitcell with antiferromagnetic bulk spin-ordering, analogous to their 2D counterpart. All the ribbons exhibit indirect band-gap semiconducting behavior and the gap decreases with increase in width of the ribbons. The nanoribbon with only phosphorus (P) atoms at least along one of the edges show half-metallic behavior over a small bias window, when probed with cross-ribbon external electric field. Especially, the nanoribbon with odd number of Si atoms stabilizes in a ground state with net non-zero magnetization and exhibits half-metallicity only under forward bias. Such anisotropic half-metallicity along with the precise control of the electronic properties in terms of edge and external bias manipulation hold immense potential for spintronic and switching device applications.

Controlling the electronic and magnetic properties of the GeAs monolayer by generating Ge vacancies and doping with transition-metal atoms.

Controlling the electronic and magnetic properties of two-dimensional (2D) materials is a key step to make new multifunctional candidates for practical applications. In this work, defects and doping with transition metals (TMs = V, Cr, Mn, and Fe) at Ge sublattices are proposed in order to develop novel features in the hexagonal germanium arsenide (GeAs) monolayer. The pristine GeAs monolayer is a non-magnetic indirect gap semiconductor with an energy gap of 1.20(1.82) eV as provided by PBE(HSE06)-based calculations. A single Ge vacancy metallizes the monolayer, preserving its non-magnetic nature. In contrast, significant magnetization with a total magnetic moment of 1.96 μ B is achieved by a pair of Ge vacancies. Herein, the computed band structures assert the half-metallic behavior of the defective system. Similarly, half-metallicity is also obtained by V, Mn, and Fe doping. Meanwhile, the Cr-doped GeAs monolayer is classified as a diluted magnetic semiconductor 2D system. In these cases, magnetic properties are produced mainly by TM-3d electrons with total magnetic moments between 2.00 and 4.00 μ B. Further, the effects of substituting a pair of Ge atoms with a pair of TM atoms (pTMGe systems) are also investigated. Results indicate the ferromagnetic half-metallicity of the pVGe system, meanwhile antiferromagnetic ordering is stable in the remaining cases. In all cases, TM impurities transfer charge to the host GeAs monolayer since they are surrounded by As atoms, which are more electronegative than dopant atoms. Results presented herein may introduce new 2D systems - made from the non-magnetic GeAs monolayer - for spintronic applications with suitable electronic and magnetic features controlled mainly by transition metals.

Structural, electronic, magnetic, and thermoelectric properties of full-Heusler alloys A2CoS (A=Cu, Zn) for spintronic application via conceptual DFT study

Half metallic ferromagnets play a pivotal role in spintronic applications. Our study focuses on theoretically predicted half metallic ferromagnetic compounds, determined through density functional theory calculations utilizing a first principles approach. The calculations involved the use of Perdew-Burke-Ernzerhof (GGA) and GGA + U exchange correlation energies. Structural analysis revealed the ferromagnetic nature, while electronic properties confirmed the half metallic behavior of these compounds-specifically, Cu2CoS and Zn2CoS. Our findings suggest that within a certain lattice parameter range, both compounds exhibit ferromagnetic behavior. However, beyond this range, Cu2CoS and Zn2CoS do not demonstrate ferromagnetism. Furthermore, our interest lies in examining their thermoelectric behavior using semi-classical Boltzmann transport theory. These results offer valuable insights for leveraging these materials in spintronics applications.

Theoretical Investigations of the Structural, Dynamical, Electronic, Magnetic, and Thermoelectric Properties of CoMRhSi (M = Cr, Mn) Quaternary Heusler Alloys

The structural, dynamical, electrical, magnetic, and thermoelectric properties of CoMRhSi (M = Cr, Mn) quaternary Heusler alloys (QHAs) were investigated using density functional theory (DFT). The Y-type-II crystal structure was found to be the most stable configuration for these QHAs. Both CoCrRhSi and CoMnRhSi alloys possess a half-metallic behavior with a 100% spin-polarization as the majority spin channel is metallic. On the other hand, the minority spin channel is semiconducting with narrow indirect band gaps of 0.54 eV and 0.57 eV, respectively, along the Γ−X high symmetry line. In addition, both CoCrRhSi and CoMnRhSi alloys possess a ferromagnetic structure with total magnetic moments of 4 μB, and 5 μB, respectively, which are prominent for spintronics applications. The thermoelectric properties of the subject QHAs were calculated by using Boltzmann transport theory within the constant relaxation time approximation. The lattice thermal conductivities were also evaluated by Slack’s equation. The predicted values of the figure-of-merit (ZT) for CoCrRhSi and CoMnRhSi were found to be 0.84 and 2.04 at 800 K, respectively, making them ideal candidates for thermoelectric applications.