Semnan University PressProgress in Physics of Applied Materials2783-47945220251101Screening of Metal Catalysts for CO2 Conversion via Machine Learning and Molecular Simulations97106964010.22075/ppam.2025.36704.1130ENFelixOkelloDepartment of Physical Science, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210, Bondo, KenyaTimothyMandaDepartment of Physical Science, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210, Bondo, Kenya0000-0003-2418-3051LivingstoneOchiloDepartment of Physical Science, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210, Bondo, KenyaFredOkumuDepartment of Physical Science, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210, Bondo, Kenya0000-0001-6409-2555SolomonOmwomaDepartment of Physical Science, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210, Bondo, Kenya0000-0001-6069-0291DenisMageroAlupe University
P.O. Box 845 Busia- Kenya 504000009-0006-6509-5938AnthonyPembereDepartment of Physical Science, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210, Bondo, Kenya0000-0002-9819-9155Journal Article20250124This study's primary objective is to improve catalyst discovery by assessing earth-abundant metal catalysts for the conversion of CO<sub>2</sub> to methane through the use of machine learning (ML) and molecular dynamics (MD) simulations. The highest CO<sub>2</sub> binding energy on 61 metals was determined to be -9.75 eV for nickel (Ni), -8.7 eV for copper (Cu), and -7.75 eV for carbon (C). Various ML models were developed to predict binding energies on the metallic surfaces. Easily accessible properties of the metals and features obtained from molecular simulations were used as input features. RANSACRegressor, LinearSVR, HuberRegressor, OrthogonalMatchingPursuit CV, and LarsCV models exhibited high prediction accuracy with R-squared values of 0.99 and RMSE ranging from 0.18 to 0.40. Feature significance analysis revealed that density (D) is among the most significant structural features affecting binding energy. This work offers a dependable, high-throughput method for identifying efficient CO<sub>2</sub> conversion catalysts, advancing sustainable technologies.https://ppam.semnan.ac.ir/article_9640_6f75e9b246b289fa11d79a27a3cba4b9.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Exploring Bismuth-Induced Structural Modifications and Magnetic Phase Transitions in CuFe2O4 Ferrite107117964110.22075/ppam.2025.35536.1120ENHamidHamrahSchool of Physics, Damghan University, Damghan, IranAhmadGholizadehSchool of Physics, Damghan University, Damghan, Iran0000-0003-2377-6808Journal Article20241107The effects of diamagnetic bismuth substitution on the microstructural and magnetic properties of sol-gel auto-combustion citrate nitrate synthesized CuFe<sub>2-x</sub>Bi<sub>x</sub>O<sub>4</sub> (x=0.0, 0.4, 0.8, 1.2, 1.6 and 2.0) nano powders were investigated. The samples were characterized by techniques such as X-ray diffraction, Raman spectroscopy, Fourier-transform infrared spectroscopy, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, UV-Vis diffuse reflectance spectroscopy, and vibration sample magnetometer. The structural results showed a phase transition from a predominantly tetragonal structure with an I4<sub>1</sub>/amd space group to a tetragonal structure with a P ncc space group. The magnetic properties of the samples revealed a transition from a ferrimagnetic to a diamagnetic phase due to the presence of the diamagnetic Bi<sup>3+</sup>. Although the coercive field exhibited a minimum value at a substitution level of x = 0.8, the saturation magnetization was found to decrease with increasing Bi substitution, ranging from 25.04 emu/g for x = 0.0 to -0.02 emu/g for x = 2.0.https://ppam.semnan.ac.ir/article_9641_39d4b545fb02556829aab1db805021c3.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Round-Shaped Micro Bio-Lasers Utilizing Rhodamine B as a Gain Medium119125964910.22075/ppam.2025.36146.1124ENShimaVahidiPhysics Department, Semnan
University, Semnan, IranMaryamAliannezhadiPhysics Department, Semnan
University, Semnan, Iran0000-0003-2372-2404ZahraGholizadehPhysics Department, Semnan
University, Semnan, Iran0009-0001-3871-3618Journal Article20241206Biolasers, new ones that utilize incorporated protein fluorophores within microscale optical cavities to produce coherent light, have a wide range of applications in medicine, including identification, diagnosing, and treating many diseases, skin repair, controlling chemical reactions, pattern generation, etc. Therefore, a new approach to form active microcavities for micro biolaser is proposed based on dye rhodamine B (RhB) and bovine serum albumin (BSA) in the paper. The results indicate the successful production of curved-shaped active cavities. The formed biocavities' average diameters and diameter dispersion are 35.221±0.674 μm and 1.9%, respectively. The output emissions of the device are studied under optical pumping by a Diode-Pumped Solid State (DPSS) laser with the Nd: YAG gain medium operated at 532 nm and an incidence angle of 45º. The output emissions are recorded at different angles, and the high output power is observed at an angle of 90° with the pump angle. Furthermore, the design device has different modes, and the lowest linewidth at half maximum (0.35 nm) and the highest quality factor (2313) are observed at an output wavelength of 809.6 nm. Therefore, the produced laser-activated microcavities can be exploited as suitable options in medical and non-medical optical applications.https://ppam.semnan.ac.ir/article_9649_7c2c48a32443ad8f805e48520f3b26a4.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220250513Strategies to Boost the Performance of Eco-Friendly Light-Emitting Diodes, Quantum Dots Size versus Plasmonic Layer127135965210.22075/ppam.2025.37027.1135ENParastooAmiriDepartment of Intelligent Systems Engineering, College of Interdisciplinary Science and Technology, University of Tehran, IranAsgharJamshidi ZavarakiDepartment of Intelligent Systems Engineering, College of Interdisciplinary Science and Technology, University of Tehran, Iran0000-0002-4780-1281Journal Article20250302This study explores the enhancement of light-emitting diode (LED) performance through the integration of quantum dots (QDs) and plasmonic layers. Simulations were conducted using Lumerical software to analyze the effects of QD size (2, 5, and 10 nm) and plasmonic layer thickness on emitted light intensity and wavelength variations. The results demonstrate that the plasmonic layer significantly enhances the electromagnetic field near the QDs, leading to increased emission light intensity. Changing the QD size influences both the emission wavelength and intensity: smaller QDs shift the emission toward shorter wavelengths and exhibit higher intensity, while larger QDs shift it toward longer wavelengths with lower intensity. This combined approach offers an effective strategy for optimizing LED efficiency, enabling precise wavelength control and improved energy performance. The findings contribute to advancements in LED technology, high-quality displays, and energy-efficient nanoscale light sources, and also suggest promising directions for future research.https://ppam.semnan.ac.ir/article_9652_33d3b157ddc0896addfb22fa2a519097.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Study of Synthesis Dependent Physicochemical and Optoelectronic Properties of Nanocrystalline Lead Sulfide (PbS) Thin Films Deposited using Chemical Bath Deposition Method137152977810.22075/ppam.2025.37005.1134ENNarayani MadhukarGosaviMaterial Research Laboratory,
C.H.C. Arts, S.G.P. Commerce and B.B.J.P. Science College, Taloda, Dist. Nandurbar,
MS, India 425413Kunal RajabhauSaliMaterial Research Laboratory,
C.H.C. Arts, S.G.P. Commerce and B.B.J.P. Science College, Taloda, Dist. Nandurbar, MS, India 425413Rajesh ArunJoshiThin Film and Sensor Laboratory, Department of Physics, Toshniwal Arts, Commerce and Science College, Sengaon Dist. Hingoli MS India 4315420000-0003-4186-6444Sunil RGosaviMaterial Research Laboratory,
C.H.C. Arts, S.G.P. Commerce and B.B.J.P. Science College, Taloda, Dist. Nandurbar,
MS, India 425413Journal Article20250228The present paper deals with the synthesis of PbS thin films using cost cost-effective chemical route over the glass substrates at room temperature for studying the effect of deposition time on physicochemical and optoelectronic properties with the intension to test the application as an ammonia gas sensor. These 10, 20, 30, 40, and 50 min deposited thin films have been characterized for their structural properties using X-ray diffraction patterns (XRD), which revealed stoichiometric PbS thin films having a polycrystalline cubic structure with orientation along the (111) and (002) planes, with crystallite sizes varying from 18 to 22 nm. The Raman spectrum shows peaks at 92 and 143 cm-1, representing the transverse and longitudinal oscillations for chemical ionic bonds, respectively. The elemental analysis confirmed from the energy dispersive X-ray analysis spectrum infers expected and observed chemical compositions in PbS thin films. The surface topography and morphology have shown the floral distribution of grains over the substrate surface. This exhibited the effect of deposition time in the form of flower growth. PbS synthesized for 40 min represents a completely grown flower, while dipping time less than 40 min shows a slightly varying nature of the flower. Such topography could be useful for surface-related applications. The optical absorbance spectra represented the higher absorbance coefficient and energy band gap calculated to be 1.48 eV, which inferes the polaron-induced charge transfer. The ammonia gas sensitivity calculated as a function of optical absorbance in air and under gas impurging has shown at most 80% sensitivity for the thin film grown by dipping 40min in the precursor solutions.https://ppam.semnan.ac.ir/article_9778_f52b43f6e0e444510cf55c5869d8d06b.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Investigation of Thermoelectric Properties of Chalcogenide Semiconductors, MgBS3(B = Hf, Zr): First Principle Approach153164978710.22075/ppam.2025.36867.1132ENRilwan OBalogunSchool of Science and Technology, Pan-Atlantic University, Km 52 Lekki-Epe Expressway, Eleko, Ibeju-Lekki, Lagos-state, Nigeria0000-0002-6895-7808Journal Article20250211Chalcogenide crystals are used in many different industries, but most notably as energy-conversion thermoelectric materials. We have calculated the Seebeck coefficient, electrical conductivity, electronic thermal conductivity, power factor, and figure of merit of MgBS<sub>3</sub> (B = Hf, Zr) chalcogenide crystals using semiclassical Boltzmann theory and first-principles calculations. A Quantum Espresso program is used to determine the Fermi level and compute the electronic properties. The transport properties are then computed using the BoltzTraP algorithm. We first make our materials available to the public. We report on our first principle investigation of MgBS<sub>3</sub> (B = Hf, Zr), a new class of ternary semiconductor alloys. The structural and elastic properties of these constituents demonstrate their low energy of formation and mechanical stability. In the valence band maximum, the observed electronic energy band gap data show a direct electronic transition including Hf-d states (B = Hf & Zr) along the Γ-symmetry direction, as well as mixed contributions from Mg-s states, Hf-d states, and Zr-d states. Furthermore, to assess the thermoelectric potential of pure MgHfS<sub>3</sub> and MgZrS<sub>3</sub>, the temperature-dependent transport properties were examined. Among the simple measures employed were the "maximum" thermoelectric figure of merit, zT, power factor, Seebeck effect, and their anticipated thermal and electrical conductivity. It provided findings with improved zT values, higher PF, moderate Seebeck effect, and efficient thermal and electrical conductivity compared to the current state of bulk thermoelectric materials. Furthermore, we discover that it is highly improbable to get the necessary zT values for typical device applications by using several additional semiconductors, or chalcogenides perovskites, as described in our work. These results provide an excellent bulk chalcogenide database that is necessary for many potential applications in the renewable energy sector. https://ppam.semnan.ac.ir/article_9787_24ac838a6b14395dda537b1c38cde219.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Structural, Electronic, and Magnetic Properties of Mn2NbAl1-xSix (x=0.0–1.0) Alloys165174981510.22075/ppam.2025.36858.1133ENSeyyed MojtabaAlavisadr(Zareii)Department of Basic Sciences, Birjand University of Technology, Birjand, Iran0000-0003-4449-8253Journal Article20250216The structural, electronic and magnetic properties of the novel Mn2NbAl1-xSix (x=0.0–1.0) alloys were investigated by using the density functional theory. The formation and cohesive energy results confirm that all members of these series are thermodynamically stable, but the Hg2CuTi-type structure has lower stability compared to the Cu2MnAl-type structure. The results also reveal that with increment of Si content, the lattice constant decreases linearly from 6.01 to 5.88 Å, while the bulk modulus increases. The total spin magnetic moment decreases from 2.00 µB (for x = 0.0) to 0.99 µB (for x = 1.0). The results of electronic structure show that the alloys with x = 0.0, 0.25 and x = 0.50 have a half-metallic nature with a real gap in the down-spin band, and 100% spin polarization. For other alloys, the spin polarization decreased with increasing x from 0.75 to 1.0. Although 100% spin polarization was not found for all members of these series, it is quite high value which can be used in industries.https://ppam.semnan.ac.ir/article_9815_4589b8b6a21b964025a84f6499070b83.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101First-Principles Investigation of Erbium Doping and Intrinsic Defects on the Structural and Electronic Properties of Silicon Dioxide175185987310.22075/ppam.2025.37283.1142ENAdeyemi JoshuaOwolabiDepartment of Physics, Nigerian Defence Academy, Kaduna, Nigeria0000-0003-3041-2498HarunaAliDepartment of Physics, Nigerian Defence Academy, Kaduna, NigeriaMohammed YusufOnimisiDepartment of Physics, Nigerian Defence Academy, Kaduna, Nigeria0009-0002-3313-3822BenedictMachuDepartment of Physics, Nigerian Defence Academy, Kaduna, Nigeria0009-0009-7655-0993AlhassanShuaibuDepartment of Physics, Kaduna State University, Kaduna, NigeriaIsaac HyukDanielDepartment of Physics, Kaduna State University, Kaduna, NigeriaMarySamuelDepartment of Mechanical Engineering Nigerian Defence Academy, Kaduna, NigeriaOlalekan JoelAwujoolaDepartment of Computer Science, Nigerian Defence Academy, KadunaJournal Article20250331Rare-earth-doped silica (SiO₂) nanostructures have great potential for optoelectronics but little is known about the atomic-scale processes controlling their electrical behaviour in the presence of intrinsic defects and erbium (Er) doping. In order to close this gap, this work uses the Density Functional Theory with Generalized Gradient Approximation (DFT-GGA), a first-principles density functional theory, to analyse the structural and electrical changes in Er-doped SiO₂ and its defective forms. Er was used to replace Si atoms in three doping concentration models of 2.08%, 4.17%, and 6.25%, for silicon vacancies (SiV) and oxygen vacancies (OV), which were added to evaluate defect-mediated effects. Lattice expansion proportionate to Er concentration was found by structural optimisation, which was driven by Er–O bonds of 2.1 – 2.3 Å and larger ionic radius 2.45 Å and 1.46 Å for Si. Thermodynamic stability was demonstrated by formation energies ranging from -0.675 to -0.724 eV/atom, where lower energy configurations were preferred by increased Er content. Er 4f, which derives the impurity states near the conduction band, is responsible for the transition to a direct band gap. The band structure calculations show moderate Er doping at 4.17%, which shows SiO₂’s indirect band gap of 5.32 eV to the doped indirect band gap of 5.98 eV and direct band gap of 5.01 and 5.08 eV. Due to dopant interactions changing of the host matrix, the gap unexpectedly extended to 5.89 eV at 6.25% Er concentration. Oxygen and silicon vacancies further modulated electronic properties, introducing deep donor levels and reducing the gap of O<sub>V </sub> to 3.89 eV and Si<sub>V</sub> to 4.21 eV formation energy albeit at significant energetic costs. Density of states analysis highlighted hybridization between Er 4f and 5d orbitals and host O 2p and Si 3p states, enabling tailored band engineering. This work establishes a theoretical framework linking Er doping and defects to tunable electronic properties in SiO₂, offering insights for designing high-efficiency optoelectronic materials.https://ppam.semnan.ac.ir/article_9873_afafd9c0764318031eedd5700a8d3d20.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Comparative Density Functional Theory Approaches for Investigating the Electro-Optical Properties of 5CB Liquid Crystal Molecules187198989410.22075/ppam.2025.37298.1144ENYogeshKumarDepartment of Physics, School of Applied and Life Sciences (SALS), Uttaranchal University, Dehradun, Uttarakhand-248007, IndiaTikaRamDepartment of Physics, School of Applied and Life Sciences (SALS), Uttaranchal University, Dehradun, Uttarakhand-248007, IndiaNarinderKumarDepartment of Physics, School of Applied and Life Sciences (SALS), Uttaranchal University, Dehradun, Uttarakhand-248007, India0000-0001-8537-0307Journal Article20250407In the present paper, we have reported the most suitable DFT methods to investigate the electro-optical properties of the liquid crystal molecules. Hybrid as well as meta GGA functional like <em>ω</em>B97XD, M06 and PBE0 are often used to optimize and calculate the various physical, thermal and optical parameters of the molecule. These functional are often used due to their good accuracy with experimental results. The 6-311G** basis set with 22 DFT methods was used to optimize and analyse the physical as well as optical properties of the liquid crystal molecule. The theoretical results obtained by density functional theory methods found in good agreement with experimental results of the molecule.https://ppam.semnan.ac.ir/article_9894_274766460cea548fa1a55d476fbfc7ff.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Fractional Wave Propagation in Asymmetric Nonlinear Media: Implications for Metamaterial-Based Wave Control199207989710.22075/ppam.2025.37998.1149ENMaryamSabzevarFaculty of Physics, Semnan University, Semnan 35195-363, Iran0000-0003-1153-9602Mohammad HosseinEhsaniFaculty of Physics, Semnan University, Semnan 35195-363, Iran0000-0002-7169-7496MehdiSolaimaniDepartment of Physics, Qom University of Technology, Qom 1519-37195, Iran0000-0003-4111-4680Journal Article20250606This study investigates the phenomenon of superarrival in Gaussian wave packets propagating through a nonlinear fractional medium under the influence of a triangular potential barrier. The time-dependent fractional Schrödinger equation is numerically solved using the Split-Step Finite Difference method to analyze the wave packet dynamics and transmission behavior in detail. The magnitude of superarrival is quantified and examined across a broad range of physical parameters, including the fractional order, nonlinearity strength, dispersion coefficient, wave packet width, initial velocity, and potential asymmetry. Results reveal that superarrival is significantly enhanced in fractional and weakly nonlinear regimes and is highly sensitive to the degree of potential asymmetry. The observed behavior reflects the interplay between nonlocality and nonlinearity, characteristic of complex and engineered materials. These insights contribute to a deeper understanding of early arrival phenomena in wave dynamics and may provide theoretical support for controlling energy or information transport in next-generation devices. Potential applications include quantum control, signal processing in photonic systems, and the design of metamaterials with tailored transmission properties at ultrafast or subwavelength scales.https://ppam.semnan.ac.ir/article_9897_1cf2bde29cc323599a0375d73c85e7d7.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Recyclable Ag-TiO₂ SERS Substrates Fabricated via Plasma Jet Printing209216989810.22075/ppam.2025.37365.1145ENMohammad RezaAbedi JondaniDepartment of Physics, Faculty of Science, Vali-e-Asr University of Rafsanjan, Rafsanjan, IranMahdiShariatDepartment of Physics, Faculty of Science, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran0000-0002-7423-0090EshratSadeghzadeh LariPlasma and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute (NSTRI), Box 14155-1339, Tehran, IranJournal Article20250411Recyclable surface-enhanced Raman scattering (SERS) substrates are important for real-world use because they can be used multiple times and are affordable. In this study, we developed a simple and low-cost method for fabricating recyclable SERS substrates by depositing silver nanoparticles onto TiO₂ nanostructures using an atmospheric pressure plasma jet without the need for chemical reducing or stabilizing agents. TiO₂ nanoparticles were synthesized via a sol-gel process and drop-cast onto glass substrates, followed by silver nanoparticle deposition through plasma jet printing. Structural analyses using XRD and FESEM confirmed the formation of anatase-phase TiO₂ and spherical Ag nanoparticles with tunable density. The SERS activity was optimized at a 60 s deposition time, and the substrates demonstrated strong plasmonic response and excellent reusability over five UV-assisted photocatalytic cleaning cycles using Rhodamine B and Methylene Blue. The substrates maintained over 80% of their initial Raman signal intensity, with no cross-contamination observed between analytes. These results show that the Ag-TiO₂ substrates are very sensitive, stable, and can be reused, making them a practical option for real-world SERS applications.https://ppam.semnan.ac.ir/article_9898_7b9dc501afe4ee11c56a4831e20cee71.pdfSemnan University PressProgress in Physics of Applied Materials2783-47945220251101Investigation on the Electronic Properties of Functionalized MXene Nanoribbons M2XT2 (M=Ti, Zr, Sc & X=C & T=O, F) with Zigzag Edges217222974410.22075/ppam.2025.35320.1116ENMahdiShiraziniaSchool of Physics, Iran University of Science and Technology, Tehran, Iran0009-0007-9637-5876EdrissFaizabadiSchool of Physics, Iran University of Science and Technology, Tehran, Iran0000-0002-9622-1232Journal Article20240913Nanoribbons, due to their unique quantum confinement effects and surface effects, have high potential for applications in nanoelectronics and spintronics. This study investigates the electronic properties of zigzag-edged MXene nanoribbons, focusing on functionalized MXenes of the form M<sub>2</sub>XT<sub>2</sub>, where M = Ti, Zr, Sc, X = C, and T = O, F. Using density functional theory (DFT), we analyze nanoribbons with varying sizes (n = 9 to 15) and edge configurations. Our results reveal that except for 9-ZNR, 12-ZNR, and 15-ZNR, all other zigzag-edged MXene nanoribbons exhibit metallic properties, with the presence of X = C in the edge configurations being a distinguishing factor. For the semiconducting nanoribbons, the band gaps decrease uniformly with increasing width, which aligns with quantum confinement effects. We also observe that the conduction and valence bands are primarily influenced by the d-orbitals of the transition metals (Ti, Zr, Sc) and the p-orbitals of the functional groups (C, O, F), with specific band structures indicating indirect band gaps for semiconductor behavior. Our findings suggest that the electronic properties of these nanoribbons are significantly affected by their size, edge configuration, and functionalization, providing valuable insights for potential applications in electronic and optoelectronic devices. https://ppam.semnan.ac.ir/article_9744_8ad3c1db0f3411d9825cb088de789857.pdf