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Z. Liu^a,*, R. X. Wang^a, K. W. Sun^b, X. C. Ling^b, J. W. Sun^b, D. H. Chen^c
Chalcogenide Letters, Vol.20, No.7, pp. 439-447, 2023, DOI:10.15251/CL.2023.207.439
Abstract Gd₂O₃:Er³⁺ @Gd₂O₃:Yb³⁺ core-shell nanofibers with cubic phase were successfully fabricated by electrospinning method. The structural, morphological properties were investigated by X-Ray diffraction, scanning electron microscopy. Under 980 nm excitation, the upconversion photoluminescence in visible light exhibits strong red emitting band with obvious splitting peaks resulted from stark splitting of energy level. The visible emissions are sensitive to temperature in the range of 303-543 K. The red emission displays quenching with elevation of temperature. The activation energy for thermal quenching is equal to 0.1408 eV. The temperature dependent multi-peaks of red emission were systematically investigated. Based on More >

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J. S. Mohammed^a,*, F. K. Nsaif^b, Y. M. Jawad^a, K. A. Jasim^b, A. H. Al Dulaimi^a
Chalcogenide Letters, Vol.20, No.7, pp. 449-458, 2023, DOI:10.15251/CL.2023.207.449
Abstract In this work, As₆₀Cu_40-xSe_x thin films were synthesized, and the pulsed laser deposition method was used to study the effected partial replacement of copper with selenium. The electrical characteristics and optical characteristics, as indicated by the absorbance and transmittance as a function of wavelength were calculated. Additionally, the energy gap was computed. The electrical conductivity of the DC in the various conduction zones was calculated by measuring the current and voltage as a function of temperature. Additionally, the mathematical equations are used to compute the energy constants, electron hopping distance, tail width, pre-exponential factor, and density More >

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M. K. Butt^a, S. Saleem^a, F. F. Al-Harbi^b, S. Atta^a, M. Ishfaq^a, F. S. Al Juman^c, M. Yaseen^a,*
Chalcogenide Letters, Vol.20, No.7, pp. 459-467, 2023, DOI:10.15251/CL.2023.207.459
Abstract The full potential linearized augmented plane wave (FP-LAPW) approach based on the density functional theory (DFT) is employed to know the effect of Co doping on the electronic, optical, and magnetic characteristics of BaTi_1-xCo_xO₃ at x= 8.33%, 16.66%, 25%, and 50%. The computed spin-polarized electronic band structure (BS) and the density of states (DOS) elucidate that the BaTi_1-xCo_xO₃ compound has a ferromagnetic semiconductor behavior at all doping concentrations. The results indicate that the magnetic moment in BaTi_1-xCo_xO₃ is found due to the p-d hybrid orbitals of Co. Moreover, the optical features of the Co-doped BTO compound are More >

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E. Lu^*, M. Q. Wu, L. L. Dai, X. Y. Xu
Chalcogenide Letters, Vol.20, No.7, pp. 469-476, 2023, DOI:10.15251/CL.2023.207.469
Abstract This study used a simple one-step hydrothermal method to synthesize the MoS₂/GR composites with a new morphology composed of graphene nanotubes and ultra-thin molybdenum disulfide with the help of sodium chloride. The composites were characterized by XRD, XPS, SEM, TEM, and a series of characterization methods. Meanwhile, the tribological properties of the composites were studied. The results show that the addition of 1% MoS₂/GR composite nanotubes has excellent tribological properties. In addition, the structure and excellent tribological properties of MoS₂-C- nanocomposite lubrication materials will be conducive to designing new nanomaterials with 2D/3D structures, enhancing the anti-friction and More >

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R. H. Athab, B. H. Hussein^*
Chalcogenide Letters, Vol.20, No.7, pp. 477-485, 2023, DOI:10.15251/CL.2023.207.477
Abstract Zinc Telluride ZnTe alloys and thin film have been fabricated and deposited on glass substrates by thermal evaporation method which may be a suitable window layer of zinc telluride with different annealing temperatures (373 and473) K for 60 minutes in vacuum. Deposited thin films with thickness 100 nm was characteristic by using X-ray diffraction XRD to know structures, Atomic Force Microscopy (AFM) to evaluate surface topology, morphology. It was found out that the vacuum annealing improves on thin ZnTe films structure and surface morphology. Structural analysis reveals that ZnTe films have zinc blende structure of More >

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S. Sultanbekov^a, O. Prikhodko^b, N. Almas^c,*
Chalcogenide Letters, Vol.20, No.7, pp. 487-496, 2023, DOI:10.15251/CL.2023.207.487
Abstract The optical properties of Ge₂Sb₂Te₅ thin films were studied as a function of thickness. An increase in optical band gap with decreasing film thickness has been observed. The current– voltage characteristics measured in Ge₂Sb₂Te₅ thin films in the current mode are studied. A decrease in switching time and threshold voltage with decreasing film thickness is established. More >

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A. M. Jawore^a, T. Xaba^a,*, M. J. Moloto^b
Chalcogenide Letters, Vol.20, No.7, pp. 497-505, 2023, DOI:10.15251/CL.2023.207.497
Abstract Nickel sulfides nanocrystals may be regarded as promising of materials in different research areas such as catalysts, solar cells, and electrode-materials. (Z)-2-(pyrrolidin-2-ylidene) thiourea ligand and (Z)-2-(pyrrolidin-2-ylidene) thiourea based nickel (II) complex have been prepared and utilized as single source molecular precursor for the synthesis of nickel sulfide nanoparticles and thin films. The effect of temperature was studies during the synthetic processes. The synthesized nanomaterials were characterized with various instruments. UV-Vis spectroscopy results of the nanoparticles were red shifting when the reaction temperature was increased whereas the blue shift was observed when the temperature was elevated More >

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D. Said^a, N. M. Samsudin^a, M. M. Naaim^a, M. I. Sayyed^b, M. H. M. Zaid^c, M. N. Azlan^d, S. M. Iskandar^e, N. N. Yusof^e, E. S. Sazali^f, R. Hisam^a,*
Chalcogenide Letters, Vol.20, No.7, pp. 515-533, 2023, DOI:10.15251/CL.2023.207.515
Abstract (80-x)B₂O₃-xTeO₂-10Li₂O-Al₂O₃ (x=10-60 mol%) mixed glass former (MGF) glasses were prepared by using melt-quenching method to investigate the effect of mixed glass former between B₂O₃ and TeO₂ on the optical properties and to evaluate the radiation shielding ability of the glass. Extremes observed at x=40 mol% for all optical properties’ parameters were suggested due to large number of non-bridging oxygen. The radiation shielding properties of the glass samples were determined for 0.284 MeV–1.333 MeV energy range by using Phy-X/PSD software. The studied radiation parameters have shown enhancement due to high density and high atomic number, Z of Te More >

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S. Mahla^a, R. Agrawal^b, S. Kumar^c, P. Singh^d, M. Lal^e, S. Singh^f, A. S. Verma^g,h,*
Chalcogenide Letters, Vol.20, No.7, pp. 535-547, 2023, DOI:10.15251/CL.2023.207.535
Abstract A subclass of ternary intermetallic known as Heusler compounds is being employed in the steel industry to increase material strength. This study examines the structural, electrical, optical, and magnetic properties of Co₂VZ (Z=Al, Bi, Ge, Si) compounds using two different methods. First is full potential linearized augmented plane wave (FP-LAPW) method by WIEN2k and second is pseudo potential method by Atomic Tool Kit-Virtual Nano-Lab. The equivalent energy gaps in the minority-spin of Co₂VZ (Z= Al, Bi, Ga, Ge) with WIEN2k code, which displays 100% spin polarization, are 0.703, 0.384, 0.186, and 0.67 eV near to the More >

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