This article presents the electronic and optical properties, as well as the performance assessment, of a thermoelectric generator utilizing Bi2Te3 through simulation studies. The computational methods employed include density functional theory and molecular dynamics. Analysis of the electronic band structure confirms the presence of a direct bandgap, while the multiple local maxima identified in the density of states suggest that Bi2Te3 can sustain high charge carrier concentrations. The absorption spectrum indicates significant absorption across the visible to infrared spectrum, and the optical conductivity peak at 4.8 eV signifies a robust electronic response linked to interband transitions. It was found that the lattice thermal conductivity decreases with increasing temperature due to enhanced phonon scattering, whereas the electronic thermal conductivity rises with temperature as more charge carriers undergo thermal excitation. Conversely, electrical conductivity decreases, primarily due to the predominance of phonon scattering at elevated temperatures. The Seebeck coefficient increases with temperature, which is attributed to the broadening of the energy distribution of electrons, thereby enhancing charge carrier participation in the thermoelectric mechanism. By integrating these calculated thermoelectric properties, the dimensionless figure of merit (ZT) was derived, and the efficiency of the Bi2Te3-based thermoelectric generator was estimated to be ∼7.56% when the sink temperature is held constant at 300 K while varying the source temperature between 300 and 800 K.

The interplay between magnetism and superconductivity in Fe-based superconductors remains a topic of significant interest. This study investigates the electronic structure and superconducting properties of LiFeAs in ferromagnetic (FM), antiferromagnetic (AFM), and non-magnetic states using Density Functional Theory (DFT) and DFT+U approximations. Notably, the DFT approximation favors AFM coupling, but DFT+U stabilizes an FM configuration in spin-polarized simulations. The DFT approximation predicts a lattice parameter of 3.651 Å, a mean-field AFM/FM transition temperature [Tc(MFA)] of 38.7 K, and a magnetic moment of 1.47 μB per Fe atom. In contrast, DFT+U yields a lattice parameter of 3.768 Å, closely matching the experimental value of 3.771 Å. It also predicts a significantly enhanced Tc(MFA) of 464.2 K and a magnetic moment of 3.13 μB per Fe atom. The significance of these findings lies in the ability of DFT+U to capture electron correlation effects better, leading to structural and magnetic properties that align more closely with an experimental observation of 3.42 μB. Finally, the DFT+U approximation structure increases bond length and angle by 0.1995 Å and 1.424°, respectively, compared to the DFT approximation. The non-magnetic state appears most favorable for superconductivity, whereas FM and AFM states suppress superconducting behavior because of spin polarization effects. This analysis provides valuable insights into the delicate balance between magnetism and superconductivity in Fe-based materials, contributing to the theoretical understanding of their electronic properties.

This study investigates the structural, electronic, magnetic, phonon, and superconducting properties of lanthanum (La)-doped yttrium hydrogen selenide using density functional theory (DFT) in combination with the phonopy package. Structural analysis reveals that La doping induces lattice expansion in YHSe. The electronic structure calculations reveal that La doping modifies both the bandgap and the electronic density of states (DOS), indicating significant changes in the electronic properties. Magnetic analysis shows that both pristine and La-doped YHSe systems are nonmagnetic, with no atomic contributions to the overall magnetic moment. Analysis of the phonon dispersions and DOS across varying La concentrations reveals pronounced shifts in vibrational modes, especially in the low-frequency region. This behavior is attributed to the larger atomic mass of La relative to Y, Se, and H, which enhances the phonon DOS (PDOS) at lower frequencies. Furthermore, La incorporation softens both optical and acoustic phonon branches, suggesting weakened interatomic bonding. The superconducting properties, evaluated through electron-phonon coupling (EPC) (lambda) calculations, indicate an enhancement in the critical temperature (Tc) and coupling strength up to 0.5 La concentrations. For all four alloys, lambda increases with La doping initially, reaching its maximum before slightly decreasing at higher concentrations. The highest observed Tc values range from 28.321 to 39.861 K, with the EPC varying from 0.8267 to 1.3774 at optimal doping levels. The estimated superconducting critical temperatures are 28.321 K for YHSe, 35.399 K for La0.3Y0.7HSe, and 39.681 K for La0.5Y0.5HSe, highlighting that doping is an effective strategy for enhancing transition temperatures in this material class without requiring high external pressure. These results highlight the potential of La-doped YHSe for thermoelectric applications due to its tunable phonon characteristics and reduced thermal conductivity.

In this study, we employed Density Functional Theory to explore the electronic structure and superconducting properties of pristine LiFeAs and 50 LiFe_0.5 Ru_0.5 As). The calculations were performed using the Quantum ESPRESSO package with projector-augmented wave pseudopotentials and the Perdew–Burke–Ernzerhof exchange–correlation functional. Superconducting characteristics were evaluated within the framework of Density Functional Perturbation Theory, through which we determined the superconducting transition temperature ( T_c ), electronic density of states, phonon dispersion relations, electron–phonon coupling constant ( λ ), Eliashberg spectral function [ α^2F(ω ) ], and the logarithmic average phonon frequency ( ⟨ω_log⟩ ). The optimized lattice parameters were determined to be a = 3.34 A and c = 5.32 A for LiFeAs, and a = 3.50 A and c = 5.43 A for LiFe_0.5 Ru_0.5 As, in good agreement with previously reported theoretical values. The phonon dispersion curves of both LiFeAs and LiFe0.5Ru0.5 As exhibit no imaginary frequencies, confirming their dynamical stability in this study. Nevertheless, the calculated superconducting transition temperatures ( T_c ) at 0 kbar and 600 kbar were 0.639 K and 4.38 K, respectively, both significantly lower than experimental measurements. Ru_0.5 This discrepancy suggests that, beyond electron–phonon coupling, additional mechanisms particularly spin and orbital fluctuations likely play a significant role in driving superconductivity in Fe-based compounds.

In this work, the structural, mechanical, electronic, optical and magnetic properties of the RhNbSb half‐Heusler compound were examined and analyzed using density functional theory (DFT). According to the results, type I atomic arrangement is structurally the most stable for the compound. In all three of its atomic arrangement types, the compound is mechanically stable and ductile according to the analysis of its mechanical properties. Generalized gradient approximation (GGA) + U approach was applied in addition to GGA approach, where U is Hubbard parameter, to increase the accuracy of results in electronic band structure, density of states (DOS), and magnetic moments. Therefore, electronic band structure and DOS calculations demonstrate that the compound exhibits metallic properties in both its type I and type II atomic arrangements with GGA predictions. However, under GGA + U calculations, the compound becomes half metal when in type I but it still reflects metallic nature when in type II. The compound’s half‐metallic nature in type I under the GGA+ U method suggests that it may be a good fit for spintronics applications in this type I of its atomic arrangement. The calculated total magnetic moment of the compound under GGA + U approach exactly fits with Slater–Pauling rule of half‐metallic nature in its type I atomic arrangement, a result that supports half‐metallic nature of the compound in type I atomic arrangement for electronic properties under GGA + U prediction. Furthermore, the compound might be taken into consideration for optoelectronic applications according to the results of computed optical characteristics.

First-principles investigation of the electronic structure and magnetic properties of Pt-doped LiFeAs superconductors was performed using density functional theory (DFT) as implemented in the Quantum-Espresso package. The calculations employed the PWscf code with projector-augmented-wave (PAW) pseudopotentials and the Perdew-Burke-Ernzerhof (PBE) exchange correlation functional. Platinum doping levels of 12.5%, 25%, 50%, and 100% were systematically investigated to assess their influence on the electronic and magnetic behavior of LiFeAs in nonmagnetic (NM), ferromagnetic (FM), and anti-FM (AFM) configurations. The computed band structures, total density of states (TDOS), partial DOS (PDOS), and magnetic moments reveal that Pt doping causes notable redistribution of electronic states near the Fermi level and progressively suppresses magnetic ordering. In the pristine compound, Fe atoms exhibit magnetic moments of similar to 1.76 mu B in the FM state and 1.58 mu B in the AFM state, confirming significant spin polarization and the energetic favorability of AFM ordering. Upon Pt substitution, the Fe magnetic moments are reduced, and Pt atoms contribute negligibly to the total magnetism ( < 0.05 mu B), consistent with their closed d-shell character. For NM configurations, the DOS at the Fermi level, N (E-F), decreases from 5.08 to 4.12 states/eV as the Pt doping level increases from 12.5% to 25%. In FM and AFM configurations, N (E-F) values further drop to 2.10 and 1.74 states/eV, respectively. This reduction in N (E-F) with increasing Pt content implies a weakening of the superconducting pairing channels, suggesting a suppression of superconductivity. However, the observed trends in DOS provide indirect but valuable insights into the interplay between electronic structure, magnetism, and superconductivity. These findings offer a theoretical foundation for tuning the magnetic and electronic properties of Fe-based superconductors via Pt doping and pave the way for future investigations incorporating explicit superconductivity-related calculations.

This study performed first-principles calculations using Density Functional Theory (DFT) and DFT+U within the Quantum-Espresso package. . The electronic structure and magnetic properties of Ru-doped LiFeAs were systematically analyzed at doping concentrations of 25%, 50%, and 100%, revealing significant modifications induced by Ru substitution. The optimized lattice parameter of pristine LiFeAs is 3.767 Å, in excellent agreement with the experimental value of 3.77 Å. Upon 25% Ru substitution, the lattice parameter expands slightly to 3.786 Å, reflecting the structural response to partial Ru incorporation. The computed electronic structure and magnetic properties of LiFe1−xRuxAs confirm its metallic nature, with no detectable band gaps. Density of States (DOS) calculations reveal that the conduction band near the Fermi level is primarily dominated by Fe-3d and Ru-4d orbitals, while the valence band is largely influenced by As-p states. With 25% Ru substituted, the electronic band structure shows a strong buildup of states close to the Fermi level, suggesting that the material is becoming more metallic. This elevated electronic density at the Fermi surface is likely to have a substantial impact on the material’s superconducting behavior and charge transport properties, potentially enhancing its conductivity and modifying the electron pairing interactions. In the ferromagnetic (FM) configuration, Ru doping enhances both spin polarization and metallicity, whereas the antiferromagnetic (AFM) state exhibits a suppressed DOS near the Fermi level. The inclusion of the Hubbard U correction provides improved insight into localized electron interactions, particularly in the Fe 3d orbitals. This study contributes to a deeper understanding of the interplay between doping, electronic correlation, and magnetism in iron-based superconductors. The pristine, 25, and 50% Ru-doped LiFeAs systems retain AFM coupling, while full (100%) Ru substitution induces a transition to a nonmagnetic state. The magnetic moments of Fe atoms decrease progressively with increasing Ru concentration, indicating a suppression of magnetism.

Structural, mechanical, electronic, optical and magnetic properties of the cubic RhNbZ (Z = Li, Si, As) half-Heusler compounds is reported using density functional theory (DFT) as implemented in quantum espresso simulation package. Structurally, the compounds are most stable when they are in type I atomic arrangement. Studies of mechanical properties indicate that all the three compounds are ductile in nature and mechanically stable. Calculations of electronic band structure and density of states (DOS) affirm that RhNbSi is a semi-conductor with an indirect band gap of 0.662 eV and 1.0095 eV from generalized gradient approximation (GGA) and GGA+U approaches respectively, where U is Hubbard parameter, RhNbLi has metallic property under both GGA and GGA+U approaches whereas RhNbAs has metallic nature under GGA prediction but it has half-metallic property under GGA+U approach, a property which is essential for spintronic applications. Optical parameters such as dielectric function, reflectivity, refractive index, extinction coefficient, absorption coefficient, optical conductivity and electron energy loss were estimated in the photon energy range of 0-40 eV. Results from these properties calculations reveal that both absorption coefficient and optical conductivity have maximum values whereas electron energy loss has minimum value in the lower energy ranges which show that the materials under our study can be considered as potential candidates for optoelectronic applications. From magnetic property calculations, RhNbSi is predicted to be nonmagnetic material but RhNbLi and RhNbAs have magnetic nature.

This study investigated the potential of pentagraphene (PG) as a high-performance thermoelectric material for energy conversion applications. Electronic structure calculations revealed that PG is an indirect bandgap semiconductor with a bandgap energy of 2.11 eV and exhibits anisotropic dielectric and plasmon properties. The phonon dispersion calculation shows that the material is dynamically stable under small perturbations. Furthermore, compared with graphene, PG has a lower phononic thermal conductivity. Thermoelectric property calculations show that PG has a significantly higher figure of merit (ZT) of 0.15 at 300 K than graphene, with a ZT of 0.009. Moreover, the ZT of PG increases with temperature, reaching 0.52 at 900 K. Simulations of a PG-based thermoelectric generator (TEG) demonstrate an efficiency of 7% at a heat source temperature of 900 K. This finding suggests that PG possesses thermoelectric properties superior to those of graphene and holds significant potential for the development of more efficient and practical TEGs, particularly for applications requiring moderate temperatures.

In this study, density functional theory (DFT) as it is implemented in the Quantum Espresso simulation package was employed to investigate the structural, electronic, mechanical and optical properties of RhZrZ (Z = As, Sb) half‐Heusler compounds. Results reveal that both the two compounds are most stable in α phase. Analysis of mechanical properties shows that the compounds are ductile in nature and mechanically stable. Calculations of band structure and density of states indicated that they are semiconductors with RhZrAs direct and RhZrSb indirect band gap. Furthermore, the investigation of the optical properties reveals that there is a high absorption coefficient and low electron energy loss in visible and some ultraviolet energy spectrum indicating that these compounds are potential candidates for optoelectronic applications.

Bismuth oxyhalide (BiOX) represents a class of layered materials distinguished by unique physicochemical and optical characteristics. This study delivers an extensive investigation into the properties of BiOX crystals, employing first-principles calculations to analyze the electronic band structure, projected density of states (PDOS), Raman and infrared (IR) spectra, dielectric functions, alongside phonon and thermodynamic properties. The computed electronic band gaps BiOI, BiOBr, BiOCl, and BiOF crystals were determined to be 2.19 eV, 3.05 eV, 3.29 eV, and 3.43 eV, respectively. Furthermore, an analysis of the PDOS for each BiOX type indicates that the valence band maximum (VBM) primarily comprises dominant O 2p and halide X np states, while the conduction band minimum (CBM) predominantly features Bi 6p states. In addition, significant absorption edges for BiOI, BiOBr, BiOCl, and BiOF crystals, oriented along the [100] axis, were observed at wavelengths of 540 nm, 449 nm, 367 nm, and 320 nm, respectively. The Raman spectral analysis revealed a noticeable shift correlating with the increasing number of halogen atoms, with intensity enhancements observed at elevated temperatures. Phonon dispersion studies corroborated the geometric stability of the optimized structures of BiOX crystals. Thermodynamic evaluations suggested that BiOX materials exhibit qualities characteristic of hard materials at higher temperatures while displaying softer material attributes at lower temperatures. In summary, this research substantially enriches the current understanding of bismuth oxyhalides by detailing their structural, electronic, optical, phonon, and thermodynamic properties. The findings presented in this study provide a foundational basis for future advancements in photocatalytic applications and material development.

The adsorption behavior of different dyes (methylene blue (MB), methyl orange (MO) and methyl red (MR)) on the BiOCl surface was investigated through density functional theory calculations and Monte Carlo dynamic simulations. The results indicate that the majority of electrons within the dye molecules are involved primarily in bonding interactions, which contributes to a stable electronic configuration in aqueous environment. Moreover, the calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of the dyes demonstrated that they have distinct electronic characteristics, with respective values of HOMO approximately −4.25, −5.70, and −5.53 eV respectively, whereas their corresponding LUMO levels were −4.25, −5.70, and −5.53 eV, respectively. Quantum theory of atoms in molecules analysis shows three critical points (atom, bond and ring) were observed in each dye. The 2D-reduced density gradient graph and 3D isosurfaces of the non-covalent interaction analysis for the three dye confirms repulsive, attractive and weak interactions. Furthermore, the molecular electrostatic potential map analysis of the dyes revealed regions of varying potential values indicating both nucleophilic and electrophilic sites. A stronger affinity of MO for the surface was observed, with a adsorption energy of −89.34 kcal/mol, compared with −70.82 and −60.55 for MB and MR, respectively. These findings underscore the potential of BiOCl not only as a superior photocatalyst but also as an efficient sorbent for dye removal in wastewater treatment applications.

Agricultural runoff, fuel spillages, urbanization, hospitalization, and industrialization are some of the serious problems currently facing the world. In particular, byproducts that are hazardous to the ecosystem have the potential to mix with water used for drinking. Over the last three decades, various techniques, including biodegradation, advanced oxidation processes (AOPs), (e.g., photocatalysis, photo-Fenton oxidation, Fenton-like oxidation, and electrochemical oxidation process adsorption), filtration, and adsorption techniques, have been developed to remove hazardous byproducts. Among those, AOPs, photocatalysis has received special attention from the scientific community because of its unusual properties at the nanoscale and its layered structure. Recently, bismuth based semiconductor (BBSc) photocatalysts have played an important role in solving global energy demand and environmental pollution problems. In particular, bismuth-based Z-scheme heterojunction (BBZSH) is considered the best alternative route to overhaul the limitations of single-component BBSc photocatalysts. This work aims to review recent studies on a new type of BBZSH photocatalysts for the treatment of contaminated water. The general overview of the synthesis methods, efficiency-enhancing strategies, classifications of BBSc and Z-scheme heterojunctions, the degradation mechanisms of Z- and S-schemes, and the application of BBZSH photocatalysts for the degradation of organic dyes, antibiotics, aromatics compounds, endocrine-disrupting compounds, and volatile organic compounds are reviewed. Finally, challenges and the future perspective of BBZSH photocatalysts are discussed.

Bismuth oxychloride (BiOCl) is a layered compound known for its exceptional physical, chemical, and optical characteristics, along with notable photocatalytic performance under visible light irradiation. This investigation employed density functional theory (DFT) to analyze the electronic band structure, projected density of states (PDOS), joint density of states (JDOS), and dielectric functions of both pristine BiOCl and various doped crystalline structures utilizing a projected augmented wave basis set. The crystallographic symmetry of doped and co-doped configurations exhibited congruency with the pristine crystals. Electronic band structures were evaluated for pristine, doped, and co-doped crystalline forms. In the case of the co-doped SnxBi1−xOBrxCl1−x crystal (x = 0.0625, 0.125, and 0.25), energy band gaps of 1.40 eV, 1.42 eV, and 1.5 eV were determined, respectively, signifying a reduction in the energy band gap compared to the single doped and undoped BiOCl crystal. Analysis of the PDOS revealed that the valence band (VB) of the SnxBi1−xOBrxCl1−x crystal was characterized by Cl (p), Br (p), O (p), and Sn (s, p) states, while the conduction band (CB) primarily consisted of Bi (p) states. JDOS calculations indicated a shift in peak energy towards lower values, indicating that dopants promoted electron transitions from Cl, Sn, O, and Br p states to the Bi p state. Moreover, investigation of the dielectric function for both pure and doped BiOCl demonstrated that tin-bromine co-doping induced modifications in the static dielectric constant and dielectric permittivity of the unmodified BiOCl crystal. Ultimately, the incorporation of tin and bromine through co-doping exerted a substantial influence on the electronic and optical properties of the doped crystalline materials. Based on our computational assessments, the SnxBi1−xOBrxCl1−x configuration with x = 0.25 showcased superior visible light absorption efficiency compared to other doped variations and pristine BiOCl.

The electronic, phonon, and superconducting properties of hexagonal yttrium hydrogen selenide (YHSe) are studied using density functional theory (DFT) methods. The DFT analysis revealed that the energy bandgap and density of states near the Fermi energy (ɛF) decrease with increasing pressure. Additionally, the influence of pressure on the vibrational properties of YHSe is also examined. The findings of the vibrational properties indicate a stiffening of lattice dynamics under pressure and the identification of negative Gruneisen parameters at certain high symmetry sites. This enhances and deepens the understanding of the vibrational characteristics of YHSe under extreme pressure conditions. Finally, the electron–phonon coupling (EPC) parameter (λ) is examined under different pressures. The examination of EPCs across varying pressures showed a significant increase from 0.826 (0 GPa) to 2.6287 (200 GPa), where an increase in this EPC is found to increase the superconducting critical temperature (Tc). Furthermore, the nonmonotonic relationship between the superconducting critical temperature (Tc) and external pressure (P) in the YHSe compound is observed. Initially, Tc decreases with increasing pressure and then begins to rise again, reaching its peak value at extreme pressure. These findings provide valuable insights into the pressure-dependent properties of YHSe and have important implications for the field of superconductivity in condensed matter physics.

The interfacial interaction between graphene and ferromagnetic substrate is known to bring additional controls to the intrinsic properties of graphene, in addition to inducing some novel properties to the system which may have potential application in spintronics. In this work the spin-polarized electronic structures across the graphene–ferromagnet interface has been investigated using first principles density functional theory calculation as it is implemented on Vienna ab-initio simulation package (VASP). The electronic and magnetic properties of the interface have also been investigated. The ferromagnet substrate was represented by Ni(111) and Co(111) surfaces due to their structural resemblance to graphene. The study reveals that the ferromagnet layers adjacent to the interface show a transition of spin orientation from in plane to out of plane. The critical thickness of the slab which yields the maximum shifting of the spin orientation of the ferromagnet layers is also determined. The strong hybridization between different orbitals of graphene and ferromagnet significantly affects the electronic and magnetic properties of the interface. Reduction on the local magnetic moments of the ferromagnet layers adjacent to the interface and the induced spin polarization on the graphene layer were also observed which is due to the impacts of the hybridization. This work will provide important information which can be used for efficient design of interfaces for graphene-based spintronics.

We have investigated the adsorption of nine different adatoms on the (111) and (100) surfaces of Iridium (Ir) using first principles density functional theory. The study explores surface functionalization of Ir which would provide important information for further study of its functionality in catalysis and other surface applications. The adsorption energy, stable geometry, density of states and magnetic moment are some of the physical quantities of our interest. The study reveals that the three-/four-fold hollow site is energetically the most favorable adsorption site on the (111)/(100) surface of Ir. The investigation on a wide range of coverages (from 0.04 to 1 monolayer) reveals the strong coverage dependence of adsorption energy of the adsorbate atoms. The adsorption energy is found to increase as the coverage increases, implying a repulsive interaction between the adsorbates. Strong hybridization between the adsorbates and the substrate electronic states is revealed to impact the adsorption, while the magnetic moment of the adsorbates is found to be suppressed. The Bader analysis reveals significant amount of charge transfers between the adsorbate atoms and the substrate. The binding of adsorbate atoms on the (100) surface is observed to be moderately stronger as compared to that on the (111) surface.

A novel bifunctional photocatalyst for overall water splitting and catalyst separations was realized through defect engineering approach. For the first time a systematic investigation of the photocatalytic activity in isostructural oxide is presented. The analysis are based on the optical absorption, band edge potential, energy band gap, and electrons-holes effective masses. The hole-doped Sc2Cu2O5 compound with Ca@Sc site @25%, show high optical absorption in the visible range and small effective masses efficient to suppress backward oxidation reaction. The computed band edge potentials for both valence and conduction band of the Ni@Cu site are deep enough for these compounds to be use as cocatalyst for either of redox reactions. High absorption under visible light irradiation, and increased spin moment was observed in oxygen vacancy configurations at the Cu co-ordinated defect sites, which is also characterized by the nearest bond length contraction in Cu-O sites after geometry relaxation.

This study investigates the molecular and dissociative adsorption of CO and SO molecules on the perfect and a defective Ir(111) surface. It is aimed at providing a broad spectrum of adsorption sites in terms of coordination of Ir atoms and investigating the role of surface defects on the adsorption of small molecules on the surface Ir(111). First-principles density functional theory (DFT) simulation with the generalized gradient approximation as it is implemented in Vienna ab initio simulation package has been employed for this study. Preferred adsorption sites, adsorption energies, and surface electronic structures of CO and SO molecules on the perfect and defective Ir(111) surfaces were calculated to obtain a systematic understanding on the nature of adsorption and dissociative interactions. The DFT calculation reveals the possible molecular adsorption of CO on both perfect and defective Ir(111) surface by the end-on manner (CO bond perpendicular to the surface); the later surface is found to be energetically more favorable. However, no dissociative adsorption was obtained. For SO molecule, on the other hand, both molecular and dissociative adsorption was observed. The defective surface is now less favorable in terms of adsorption energy, but yields stronger activation of SO. The nudged elastic band method investigation also reveals that the Pt single-atom catalysis significantly reduces (up to 80% reduction) the energy barrier of the dissociative adsorption of SO. The electronic structure calculation reveals that all the adsorptions investigated in this study involve hybridization of different electronic states.

We have investigated the structures and stability of two dimensional (2D) Hf clusters on Ir(1 1 1) surface as the initial stage of hafnene growth using first principles density functional theory (DFT) with the generalized gradient approximation. The study reveals that the Ir supported Hf clusters of n hexagonal rings prefer a nearly flat honeycomb structure, with the exception of n = 1. The 2D Hf clusters, unlike to that of free-standing hafnene monolayer, exhibits no magnetic property mainly due to strong hybridization with the Ir(1 1 1) surface. A thorough investigation has also identifies the most stable structures and corresponding physical properties of free standing Hf-N (N <= 24) clusters.