Dibya Prakash Rai
@pucollege.edu.in
Assistant Professor
Pachhunga University College
RESEARCH INTERESTS
Transition Metal based strongly correlated materials (Heusler compounds, half metals). Thermoelectric materials and enhancing their efficiency on doping of heavy elements. 2D single/multi atomic layers, superlattices, nanostructuring, Ferroelectric, Piezoelectricity.
FUTURE PROJECTS
Development of High Energy NASICON-Type Cathode Materials for Sodium-ion Batteries
Applications Invited
D. Saritha
"Design and Preparation of Novel Electrode Cathode/Anode Materials for high energy capacity rechargeable Na-ions Battery Experiment and ab-initio theory."
Applications Invited
D. Saritha
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Lalhumhima, Bernard Lalroliana, Lalmuanchhana, R Zosiamliana, D P Rai, R C Tiwari, and Lalhriatzuala
IOP Publishing
Abstract This work employs density functional theory (DFT) to investigate the characteristics of ATiO3 (A = Mn, Fe, Ni) by utilizing generalized gradient approximation (GGA) and DFT + U formalisms. Our results reveal that the investigated compounds exhibit a ground-state magnetic arrangement in the G-type antiferromagnetic configuration. Substitution of the A-site atoms along the row leads to a decrease in volume due to poor electronic shielding effects with transition metals. All systems investigated are stable under dynamical conditions, with no imaginary phonon. From the formation energy calculations, NiTiO3 was identified as the most formable and stable compound. DFT + U was most effective for FeTiO3, resulting in significantly wider bandgaps compared to the GGA-level bandgaps. Optical properties such as static dielectric constants, refractive index, and reflectivity were overestimated by the GGA when compared to DFT + U results. The absorption edges of FeTiO3, MnTiO3, and NiTiO3 were analyzed, with DFT + U showing delayed onset compared to GGA. FeTiO3 was found to be the most effective absorber within the visible spectrum according to DFT + U, while NiTiO3 was predicted to be the best absorber by GGA. Each compound’s mechanical stability was tested and verified based on the Born criteria, with FeTiO3 exhibiting the highest elastic moduli under DFT + U, while NiTiO3 had the highest shear and Young’s modulus according to GGA. Among the studied compounds, FeTiO3 is the best-performing and most efficient piezoelectric compound with e 16 = 5.418 C m − 2 under DFT + U. Overall, the studied compounds demonstrate promising capabilities for a wide range of applications in the field of photovoltaic devices, and piezoelectric materials, due to their remarkable optical, and piezoelectric properties.
E. Maskar, A. Fakhim Lamrani, M. Belaiche, Mountaser ES-SEMYHY, M. Khuili, Mattipally Prasad, J. Sivakumar, Amel Laref, and D. P. Rai
World Scientific Pub Co Pte Ltd
In this research, we have employed the Density Functional Theory (DFT) to successfully study the structural, elastic, thermoelectric, and optoelectronic properties of hexagonal halide perovskites CsGeX3 ([Formula: see text], Cl, and Br). We used the Modified Becke–Johnson (MBJ-GGA) potential approximation to profoundly describe the band structure. The compounds of this interesting study are ductile, anisotropic, and mechanically stable. Our study showed that the optical properties are significant, among which are the following: the absorption is higher in the ultraviolet range, and the transmittance reaches a maximum level, which is 80% in the visible and infrared ranges. These substances can be employed in various optoelectronic systems that work in visible and ultraviolet energies. Furthermore, the transport properties are remarkably improved and reached the ZT [Formula: see text]. These characteristics proved that they have an interesting potential for thermoelectric uses. We emphasized that this study provided the theoretical foundation of these structures’ elastic, electronic, and optical properties.
E Maskar, A Fakhim Lamrani, R Zosiamliana, and D P Rai
IOP Publishing
Abstract In this study, we explore the structural, electronic, thermodynamic, and thermoelectric properties of RuO2 using density functional theory. The derived equilibrium structural parameters agree with other theoretical and experimental results. The widely used modified Becke–Johnson (mBJ-GGA) potential is adopted for accurate electronic band gap estimation. To incorporate the effect of the extended orbital of the Ru atom, spin-orbit coupling has been used in combination with the mBJ potential. The investigation of electronic properties revealed an indirect semi-conducting nature with a band gap along the W-L symmetry. The calculated band gaps are 1.685 and 1.658 eV from mBJ and mBJ + SOC, respectively. The dynamical stability is tested and verified by calculating the phonon dispersion curve. We have employed the quasiharmonic approximation-based Gibbs2 package to determine the pressure and temperature-dependent thermodynamical parameters, such as cell volume, Debye temperature, heat capacity, entropy, and thermal expansion coefficient. This study uses the BoltzTraP simulation algorithm to determine the thermoelectric parameters such as the Seebeck coefficient, electrical conductivity, and thermal conductivity.
L Celestine, R Zosiamliana, Lalrin Kima, Bhanu Chettri, Y T Singh, Shivraj Gurung, N Surajkumar Singh, A Laref, and D P Rai
IOP Publishing
Abstract Recent studies have reported that lead-halide perovskites are the most efficient energy-harvesting materials. Regardless of their high-output energy and structural stability, lead-based products have risk factors due to their toxicity. Therefore, lead-free perovskites that offer green energy are the expected alternatives. We have taken CsGeX3 (X = Cl, Br, and I) as lead-free halide perovskites despite knowing the low power conversion rate. Herein, we have tried to study the mechanisms of enhancement of energy-harvesting capabilities involving an interplay between structure and electronic properties. A density functional theory simulation of these materials shows a decrease in the band gaps, lattice parameters, and volumes with increasing applied pressure. We report the high piezoelectric responses and high electro-mechanical conversion rates, which are intriguing for generating electricity through mechanical stress.
Narmin Arif Ismayilova and Dibya Prakash Rai
World Scientific Pub Co Pte Ltd
Density functional theory (DFT) analyses were carried out to study electronic structures and magnetic properties of Mn- and Cu-doped GaNNS. To investigate the influence of transition metal atoms (TM) on magnetic properties, we substituted Ga atoms with Mn and Cu atoms in different concentrations. Investigation shows that TM leads to electronic structural reconstruction which changes their properties in this way, and plays a significant role in spin polarization. Although the pure nanosheet is a nonmagnetic semiconductor, the doped atoms induce magnetism in the structure. The band gap changes monotonically depending on the concentration of TM atoms. The observed good half-metal ferromagnetism GaNNS:Mn, allows them to be a potential candidate for use in spintronics. The local magnetic moment calculated from Mulliken analyses for the Mn atom is approximately 4.05 [Formula: see text]B.
Dibya Prakash Rai, Kingsley O. Obodo, and Jitendra Pal Singh
BENTHAM SCIENCE PUBLISHERS
Kingsley O. Obodo, Lalrin Kima, Adedapo S. Adeyinka, and Dibya Prakash Rai
BENTHAM SCIENCE PUBLISHERS
First-principles DFT calculations were used to investigate surface segregation processes in ordered Pt3X (where X=Nb, Ti) alloys. Using pristine Pt (111) surface as a reference, the effect of surface segregation on the adsorption energy of O2 atoms in Pt3X alloys was evaluated. Our results showed that surface segregation due to direct exchange is only feasible for the Pt3Nb alloy (Esegr = - 0.3833 eV) but not for its Ti analogue (Esegr = 0.516 eV). In contrast, for both Pt3X alloys, surface segregation due to antisite migration and leading to the formation of a Pt-skin or overlayer, favouring oxygen atom adsorption, an essential step in ORR, is possible. Interestingly, reverse migration of X atoms from the bulk to replace Pt atoms on the surface is an endothermic process and is thus very unlikely. Analysis of the surface segregation energy for configurations involving a direct exchange of Pt atoms located beyond the third layer in the slab model with Nb atoms at the surface indicates the formation of pristine bulk like Pt (111) surface from Pt3Nb surface is unlikely. The energy of adsorption for the O-atom on pristine Pt (111) surface shows that the presence of minute quantities of dopant Nb atoms in the sub-surface layer could enhance its suitability for ORR. Comparison of O-atom adsorption energy on the various surface segregation models of Pt3X alloys to that of pristine Pt (111) surface shows that the formations of a Pt-skin or overlayer on the Pt3Nb surface due to surface segregation change the O-atom adsorption energy on this surface to 0.34 eV which is just 0.14 eV higher than the optimal value of 0.20 eV. Our results also show that the binding of an oxygen atom to the fcc Pt site in Pt3Ti is lower in energy compared to its binding on a pristine Pt (111) surface. In comparison, the binding of an oxygen atom to the fcc Pt site in Pt3Ti is of the same magnitude as that of the pristine Pt (111) surface.<br>
The discovery of new materials and the manipulation of their exotic properties for device fabrication is crucial for advancing technology. Nanoscience, and the creation of nanomaterials have taken materials science and electronics to new heights for the benefit of mankind. Advanced Materials and Nanosystems: Theory and Experiment covers several topics of nanoscience research. The compiled chapters aim to update readers by highlighting modern developments in materials science theory and experiments. The significant role of new materials in future technology is also demonstrated. The book serves as a reference for curriculum development in technical institutions and research programs in the field of physics, chemistry and applied areas of science like materials science, chemical engineering and electronics. This part covers 11 topics in these areas: 1- Role of Plasmonic Metal-semiconductor Heterostructure in Photo Catalytic Hydrolysis and Degradation of Toxic Dyes 2 -BaZrO3-Based Ceramics and Ceramic Composites as Smart Materials for Advanced Applications 3 -A High-capacity Anode Material for Lithium-ion Batteries is Sili-graphene Type SiC3 4 -An Introduction to the Fabrication of White Light-emitting Diodes 5 -Electronic and Piezoelectric Properties of Nonmetal Doped II-VI Monolayer Compounds 6- A Theoretical Investigation on the New Quaternary MAX-phase Compounds 7- Surface Segregation in Pt 3 Nb and Pt 3 Ti using Density Functional-based Methods. 8- Nanoparticles and Environmental Health 9 -Investigation for Optimum site for adsorption and population effect of Lithium on Silicene Monolayer 10- Strategies for Synthesizing Metal Oxide Nanoparticles and the Challenges 11- Heterogeneous Semiconductor Photocatalysis for Water Purification: Basic Mechanism and Advanced Strategies
E. Maskar, A. Fakhim Lamrani, M. Belaiche, A. Es-Smairi, A. Laref, M. Prasad, J. Sivakumar, and D. P. Rai
Springer Science and Business Media LLC
Bhanu Chettri, Prasanta Kumar Patra, Yumnam Thakur Singh, Zosiamliana Renthlei, Lalrinkima, Lalrinthara Pachuau, Mohammed Ezzeldien, Amel Laref, and Dibya Prakash Rai
American Chemical Society (ACS)
Lalhumhima, Bernard Lalroliana, R. Zosiamliana, Lalmuanchhana, Dibya Prakash Rai, Ramesh Chandra Tiwari, Lalmuanpuia Vanchhawng, Lalrinthara Pachuau, and Lalhriatzuala
Elsevier BV
Adil Es-Smairi, Nejma Fazouan, E Maskar, Ibrahim Bziz, Mohammed Sabil, Ayan Banik, and D P Rai
IOP Publishing
Abstract In this current study, we used the density functional theory method to examine the physical properties of ZnS nanosheets doped with Tm, Y, Gd, and Eu at a concentration of 6.25%. The non-magnetic phase is energetically stable when doped with Y and Tm. However, the ferromagnetic state is thermodynamically stable when doped with Eu and Gd, show negative formation energy. The optimised structure is a planar structure for all doped systems, with an increase in the lattice parameter and bond length. On doping, the Fermi level is pushed into the conduction band, narrowing the band gap and exhibiting typical n-type semiconducting behaviour. In a wider optical window, Tm and Y-doped systems have lower reflectance and more excellent transmittance than Gd and Eu-doped systems in the visible light spectrum. The electrical conductivity has been calculated using the BoltzTrap package. The electrical conductivity has been enhanced by doping, making it suitable for optoelectronic, solar cells, spintronics, and thermoelectrics applications.
E. Maskar, A. Fakhim Lamrani, Adil Es-Smairi, Ahmed Louardi, A. Yvaz, and D.P. Rai
Elsevier BV
R Zosiamliana, Lalrin Kima, Zodin Mawia, Lalhriat Zuala, G Abdurakhmanov, and D P Rai
IOP Publishing
Abstract In this study, we explored the electronic and thermoelectric (TE) properties of the Na-based Quaternary Heusler Alloys (QHAs) NaHfXGe (X = Co, Rh, Ir) using density functional theory (DFT). We performed the spin-polarized DFT calculations at the general gradient approximation (GGA) level and confirmed the ground state non-magnetic configuration of NaHfXGe. The mechanical and thermodynamical stabilities are analyzed and discussed to validate the stability by calculating the elastic constant and phonon dispersion curve. A thorough investigation on the electronic properties are carried out by performing the GGA, GGA+U, and GGA+SOC formalism where we report the semi-conducting characteristic of NaHfCoGe and NaHfRhGe QHAs. However, NaHfIrGe is predicted to be a non-magnetic metal. From the calculated optical properties we found that the most active optical absorption occurs within the vis–UV region with α > 105 cm−1, therefore the studied QHAs are proposed to be a promising optoelectronic materials. The results of the thermodynamic properties have shown that NaHfXGe follows Debye’s low-temperature specific heat law and the classical thermodynamics of the Dulong-Petit law at high temperatures. The calculated TE efficiency using GGA+SOC formalism at T = 1200 K are ZT∼1.22 and 0.57 for NaHfCoGe and NaHfRhGe, suggesting that these materials are potential TE materials to operate at high temperature.
A. T. Mamadalimov, N. K. Khakimova, Sh.M. Norbekov, A.Kh. Yunusov, and D. P. Rai
Springer Science and Business Media LLC
Adil Es-Smairi, Nejma Fazouan, E. Maskar, Ibrahim Bziz, Mohammed Sabil, and D.P. Rai
Elsevier BV
L. Celestine, R. Zosiamliana, S. Gurung, S.R. Bhandari, A. Banik, and Dibya Prakash Rai
Elsevier
Lalengmawia Celestine, Renthlei Zosiamliana, Shivraj Gurung, Shalika Ram Bhandari, Amel Laref, Sherzod Abdullaev, and Dibya Prakash Rai
Wiley
AbstractBy means of the study of the first principles within the framework of density functional theory, the inorganic metal halide perovskite CsGeX3 (X = Cl, Br, and I) is thoroughly investigated for its potential application in the field of green energy harvest. The structural, electronic, optical, mechanical, and piezoelectric properties have been calculated. Herein, the computed electronic properties reveal a direct bandgap semiconducting nature with electronic bandgap E = 2.01, 1.38, and 0.85 eV for X = Cl, Br, and I, respectively. Since the most prominent absorption peak falls within the vis–UV region, this implies that they are the potential candidates for photovoltaic applications. To check and verify the thermal stability, the MD simulation was performed with time steps up to 5 ps. The highest piezoelectric coefficient values are 0.731, 1.829, and 12.48 C m−2 for X = Cl, Br, and I, respectively. The higher piezoelectric responses indicate the signature of the efficient energy materials for energy harvest through electromechanical processes.
Zosiamliana Renthlei, L. Celestine, Lalrin Kima, Lalhriat Zuala, Zodin Mawia, Bhanu Chettri, Yumnam Thakur Singh, Sherzod Abdullaev, Mohammed Ezzeldien, and Dibya Prakash Rai
American Chemical Society (ACS)
Adil Es-Smairi, Nejma Fazoun, E. Maskar, Ibrahim Bziz, Ahmed Ouhammou, El Houssine Atmani, A. Laref, Samah Al-Qaisi, and D. P. Rai
World Scientific Pub Co Pte Ltd
Using the Wien2k code based on Full Potential Linearized Augmented Plane Wave approach, the density functional theory was used to examine the structural and opto-electronic properties of CuO. The 4D-optimize option and the Perdew–Burke–Ernzerhof (PBE)-sol functional are used to optimize the structural parameters. Generalized Gradient Approximation (GGA) with PBE-scheme along with the screened Coulomb interaction [Formula: see text] and modified Becke–Johnson (GGA–TB-mBJ) potential was performed for the overall calculations. The computed band energies were taken as the key input to extract the transport properties with the help of the Boltzmann transport equation. In contrast to the gap energy provided by the [Formula: see text] ([Formula: see text][Formula: see text]eV), it is demonstrated that the gap energy produced by the TB-mBJ is [Formula: see text][Formula: see text]eV, which is close to the experimental data. The optical characteristics show a high absorption coefficient in the ultraviolet region, an average transmittance of about 65% in the visible range, which covers a wide spectrum of light, and an average reflectance of about 18% in visible light. At low temperatures, the carrier mobility limits the CuO conductivity, whereas, at high temperatures, the carrier concentration dominates. CuO is a potential material for solar cell applications as an absorbent layer and antireflection coating due to these characteristics.
Samah Al‐Qaisi, Abdelazim M. Mebed, Muhammad Mushtaq, D. P. Rai, Tahani A. Alrebdi, Rais Ahmad Sheikh, Habib Rached, R. Ahmed, Muhammad Faizan, S. Bouzgarrou,et al.
Wiley
In this study, structural, electronic, optical, thermoelectric, and thermodynamics properties of vacancy-ordered double perovskites Rb2 XCl6 (X = Se, Ti) were explored theoretically. The results revealed that Rb2SeCl6 and Rb2 TiCl6 are indirect band gap (Eg ) semiconductors with Eg values of 2.95 eV, and 2.84 eV respectively. The calculated properties (phonons, elastic constant, Poisson's ratio, and Pugh's ratio) revealed that both materials are dynamically and chemically stable and can exhibit brittle (Rb2 SeCl6 ) and ductile (Rb2 TiCl6 ) nature. From the analysis of optical parameters, it was noticed that the refractive index of the materials has a value of 1.5-2.0 where light absorption was found from the visible to the ultraviolet region. The thermoelectric properties determined by using the BoltzTrap code demonstrated that at room temperature, the Figure of merit (ZT) was found to be 0.74 and 0.76 for Rb2 SeCl6 and Rb2 TiCl6 , respectively. Despite a moderate value of ZT in such materials, further studies might explore effective methods for tuning the electronic band gap and improving the thermoelectric response of the material for practical energy production applications.
Mwende Mbilo, Robinson Musembi, and D. P. Rai
Springer Science and Business Media LLC
Lalmuan Chhana, Lalrin Kima, Ramesh Chandra Tiwari, Zodin Mawia, Dibya Prakash Rai, Ningthoujam Surajkumar Singh, Yengkhom Rangeela Devi, Lalmuanpuia Vanchhawng, Shivraj Gurung, and Lalhriat Zuala
IOP Publishing
Abstract Using Density Functional Theory (DFT), 2D hexagonal silicene-ZnS-silicene trilayer heterostructure was studied with van der Waals correction as implemented in Grimme’s method. Small lattice mismatch of about 0.77% only between silicene and ZnS monolayer suggest ease in formation of sandwiched heterostructure. The negative value of total energy at 298 K from MD simulation confirms its ground state stability. Unlike monolayer silicene, our trilayer heterostructure exhibits a direct band gap of 0.63 eV in its equilibrium state. Calculated elastic moduli predict that Si-ZnS-Si has an enhanced ability to resist tensile and shear deformation than the pristine silicene and ZnS monolayer. Due to strong van der Waal’s interaction between the layers, Si-ZnS-Si has much lower thermal coefficient of linear expansion and therefore is more stable against any thermally induced deformation. When a transverse external electric field is applied, we observe direct-to-indirect band gap transition. On increasing the electric field further, the heterostructure remains indirect band gap semiconductor until it abruptly transforms to metallic nature at 1.0 V Å−1. Theoretical prediction of heterostructure property presented in this work may provide valuable data for developing future nanoelectronic devices.
M. Musa Saad H.-E., A. Almeshal, Ahmed Elhag, B. O. Alsobhi, and D. P. Rai
Springer Science and Business Media LLC