Shift Of Edge Research Articles

Ligation of Titanium-oxide and {Mo2} Units for Solar CO2 Storage.

Two Mo-Ti-mixed oxide clusters, Ti6Mo4 and Ti4Mo4, which contain the {Mo2V} unit commonly observed in many polyoxomolybdates, were successfully synthesized. The introduction of a {Mo2V} dopant into a titanium-oxide cluster (TOC) results in a red shift of the absorption edge, hence leading to a substantial enhancement of visible-light absorption. The band gap electron transition mainly involves the ligand-to-metal charge transfer (LMCT, benzoate-to-Mo) and MoV d-d transition. Both clusters show favorable visible-light responsiveness and charge-separation efficiency. Both serve as heterogeneous photocatalysts and exhibit excellent catalytic activity in CO2/epoxide cycloadditions under very mild conditions. The mechanism study suggests that the catalytically active sites are mainly MoV, and the photogenerated electrons and holes are both involved. Ti6Mo4 exhibits better photocatalytic activity than Ti4Mo4, demonstrating the crucial role of the titanium-oxide core, which corresponds to improved light absorption and charge-separation efficiency. Our findings highlight the potential of the {Mo2V} unit in constructing Mo-Ti-mixed oxide clusters with interesting topologies and excellent solar-light-harvesting activity.

Studying the structural, optical, and electrical characteristics of Zn2SnO4 films using a direct current magnetron sputtering method

In this study, the characteristics of ZTO films are examined by varying the substrate temperature at an Ar ambient pressure of 3 × 10−3 Torr. The elemental content of Zn, Sn, and O in the generated Zn2SnO4 films was confirmed using X-ray dispersive and X-ray photoelectron spectroscopy. The result reveals that the Zn/Sn ratio for the film formed at 300 °C reaches 2. The (222) and (311) lattice planes validated the cubic inverse spinel structure of ZTO films in the X-ray diffraction investigation. Atomic force microscopy was used to measure surface roughness, and the RMS rose in a range of 1.34–4.79 nm as the substrate temperature increased. Field-emission scanning electron microscopy revealed that the average crystal grain size grew in the region of 60–95 nm as the substrate temperature increased. The UV–vis absorption edge shift validates the Burstein-Moss shift rule, with a bandgap of ZTO-300 achieving the greatest value of 3.75 eV, corresponding to the largest carrier concentration. Electrical characteristics were investigated using Hall measurements. Film conductivity was primarily determined by the electron concentration or the presence of oxygen vacancies. The lowest resistivity measured was 5.4 × 10−3 Ω cm, which corresponded to an electron concentration of 8.57 × 1019 cm−3. The current-voltage characteristics of the ZTO/p-Si junction proved its rectifiable quality. Because of the low resistivity of the ZTO-300 sample, the ZTO-300/p-Si heterojunction has the largest photocurrent (4.72 10−3 A), making it suitable for use in optoelectronic devices.

Size Quantization of the Electron Energy Spectrum in a Microscopic Semiconductor Crystal

The interband absorption spectrum of microscopic CdS crystals ranging in size from ~30 to 800 Å and dispersed in a transparent insulating matrix has been studied. There is a significant (~0.8-eV) shift of the fundamental absorption edge in the short-wavelength direction, and there are oscillations in the interband absorption spectrum caused by quantum size effect.

The effect of DC power and annealing on the structural, optical, and electrical characteristics of sputtered amorphous WOX thin films

Tungsten oxide (WOX) is considered as one of the promising materials due to its unique properties in widespread optoelectronic and photonic applications. This study reports on the deposition of WOX thin films via reactive magnetron sputtering technique with various low DC power and constant sputtering pressure at room temperature. XRD results reveal that an amorphous state for all the as-deposited films, while annealed films at 650 °C have WO3 monoclinic structure. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) studies indicate all as-deposited films have a dense, homogeneous, and quite smooth surface with a root-mean-square roughness (σRMS) below 1 nm. Annealing significantly affects film morphology, the formation of large grains and increasing the surface roughness. Optical parameters were examined by ultraviolet–visible (UV–Vis) spectrophotometer. Increasing sputtering power leads to a decrease in transparency value, an increase in absorbance, a reduction in penetration depth, a red shift of the fundamental absorption edge, and a reduction in the band gap energy from 3.06 eV to 2.61 eV. The annealed films exhibit a smaller optical band gap compared to as-deposited films in the range of 2.44 eV–2.93 eV. The temperature dependence of the sheet resistance corresponds to the Arrhenius law for as-deposited films with DC power of 10 W–30 W, indicating semiconducting nature. A decreasing trend in activation energy (0.283–0.055 eV) was observed with increasing DC power. All the annealed films exhibit insulator nature with a resistance of more than 100 MΩ. Analysis of these results suggests that the desired structural, optical, and electrical properties can be achieved by controlling deposition conditions.

Correlation of sputtering power with microstructure and ionic conductivity in lithium aluminum oxide thin films prepared by reactive co-sputtering

Li–Al–O thin films synthesized via the reactive magnetron co-sputtering have the potential to act as solid-state electrolytes in micro-batteries. In this paper, the constant RF power (155 W) and variable DC power (20–50 W) were applied to lithium (Li) and aluminum (Al) metal targets, respectively, in Ar/O2 atmosphere to produce films with adequate ionic conductivity. The influence of DC sputtering power on the composition, microstructure, band gap energy, ionic conductivity, and dielectric loss of films were studied in detail. X-ray photoelectron spectroscopy (XPS) showed a shift of the Li 1s peak towards higher binding energy with increasing DC power. X-ray diffraction (XRD) spectra confirmed the amorphous state for all as-deposited films, while the post-annealed films at 950 °C contain the γ-LiAlO2 phase. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) images revealed that the increasing DC power had a significant impact on the film morphology, enlarging grain size and increasing surface roughness. Energy dispersive X-ray (EDX) spectroscopy showed that increasing the DC power increased the Al content. The optical properties were examined by ultraviolet–visible (UV–vis) spectroscopy, which indicated that increasing the Al content led to a blue shift of the absorption edge and an increase in the band gap energy (5.40–5.68 eV). Increasing the DC power resulted in an improvement of room-temperature conductivity by two orders of magnitude (∼2.85 × 10−9 S cm−1) and a decrease in the activation energy from 0.54 eV to 0.32 eV. These results suggest that composition and microstructure significantly affect the ionic transport in co-sputtered Li–Al–O films.

Product Leadership and Competitive Advantage of Commercial Banks in Kenya

Purpose: Due to increased competition, the Kenyan banking system has had erratic performance in recent years. As a result, the major question is whether Kenyan commercial banks can use value disciplines to help them maintain their competitiveness. The study aimed to investigate the effect product leadership on competitiveness of Kenyan commercial banks.
 Methodology:. The research used a descriptive research design. The study comprised of businesses rendering commercial banking services in Kenya. A non-probability method of sampling was utilized. Structured questionnaires were used as applicable. The study targeted all the 42 Kenyan commercial banks/lenders. The 42 commercial bank managers were targeted as the unit of observation and the 42 commercial banks as the unit of analysis. Since the population in the current study was small but adequate for study research, that is, 42, the study used a census survey (thus no sampling was done) and thus the targeted population were still the commercial banks. Questionnaires were the instruments of data collection. The SPSS application was used to help with this analysis (v.25.0). Descriptive analytics and inferential metrics were used to analyze the data. Charts, graphs, tables, diagrams, and illustrations were used to present the findings.
 Results: The findings indicated that product leadership has a positive and significant relationship with the competitive advantage of Kenyan lenders (β =0.359, p=0.000). This implies that gains in a single unit of product leadership result in a 0.359-unit shift in the competitive edge of Kenyan lenders.
 Contribution to policy and practice: The study reveals a positive and significant connection between product leadership and the competitive advantage of Kenyan commercial banks/lenders. This suggests that banks that focus on developing innovative products, offering unique value propositions, and staying ahead in terms of product offerings are more likely to attain a competitive advantage. This finding contributes to knowledge by emphasizing the importance of product innovation and differentiation for achieving a competitive edge in the banking industry.

An Investigation on CdSeTe/CdTe Stacks Deposited by Evaporation: Impact of Halide Treatment Depending on the Applied Surface

Among the methods applied to modify the characteristics of CdSeTe/CdTe stacks, one of the most well‐known and widely used procedures is the CdCl2 halide treatment. In this connection, the influence of CdCl2 on microstructural properties, phase distribution, and optical properties of CdSeTe/CdTe stack depending on location of the employed surface is investigated. In CdSeTe/CdTe stacks deposited by evaporation in vacuum, CdCl2 halide treatment is applied to the interface of CdSeTe and CdTe, the upper surface of CdTe, and both surface regions of the stack. CdCl2 treatment applied depending on the region has a definite effect on the phase structure, interlayer CdSexTe1−x alloying rate, and crystallization quality of the stack structure. Regardless of the applied region, all CdCl2‐treated stacks exhibit a granular and compact surface morphology. On the other hand, CdCl2 treated only on single surface results in a shift of the absorption edge to the shorter wavelength, but rather to the long spectral region for both surfaces. The photoluminescence spectra reveal the presence of band emissions of the CdTe layer and CdSeTe alloys. Overall, the findings of the study indicate that only the upper‐surface application of CdCl2 has more promising features for potential solar cell applications.

The study of optical-electrical properties of ZnO(AZO)/Si heterojunction

In this paper, zinc oxide (ZnO) thin films and Al-doped zinc oxide (AZO) films are prepared. The XRD results show that the addition of Al ions at the middle stage of AZO film (ms-AZO) preparation can increase the grain size and change the preferential growth orientation from (100) crystal plane to (002) crystal plane. The results of UV-VIS spectra show that the addition of Al ions at the ms-AZO preparation can greatly increase the absorption intensity in the visible light region, and the addition of Al ions at the early stage of AZO film (es-AZO) preparation can make the blue shift of the ultraviolet absorption edge. The patterns of I–V curves show that the addition of Al ions can increase the forward current of AZO/Si heterojunction, comparing to that of ZnO/Si heterojunction. Furthermore, the leakage current mechanism may dominate the carrier transport.

Yellow TiO2 from titanium peroxo complexes: Verification of the visible light activity and a rational enhancement of its photocatalytic efficiency

It is widely believed that colored TiO2 materials (yellow, blue, black, violet, etc.) are visible-light active photocatalysts. In this article, we verify this claim with respect to the yellow TiO2 photocatalyst that has been synthesized using peroxo-titanium complexes formation route. The surface oxygen species, the electronic structure, the photoelectrochemical properties, and the photoactivity of yellow TiO2 have been investigated. FT-IR and XPS analysis confirms the presence of surface peroxo-species that caused the yellow color. Spectroelectrochemical measurements confirmed the absorption of violet light (400–430 nm). The reduced band gap energy (3.05 eV) has resulted from the anodic shift of both conduction and valence band edges by 0.30 and 0.15 eV, respectively. However, the wavelength-dependent photocurrent generation by yellow TiO2 in the presence of oxygen and under deaerated conditions proved that it does not contribute to the photoactivity enhancement in the visible region (λ > 400 nm). The proposed mechanism has shown that although the driving force at the oxidation side is theoretically improved, the reduction counterpart is parallelly weakened and the photoinduced electrons cannot efficiently reduce regular electron acceptors in aqueous systems (e.g., O2, H2O). Adding a low amount of a stronger electron acceptor (e.g., H2O2) into the system provides extra HO• radicals through the reductive mechanism. At higher concentrations of H2O2, the oxidation of H2O2 is more favorable. The hydroxylation of terephthalic acid via the oxidative and reductive pathway along with the bleaching of Congo Red indicates improved photocatalytic activity due to enhanced hydrogen peroxide activation. Although yellow TiO2 is active only upon UV light irradiation, this paper reports how to boost the photocatalytic activity of this material.

Effect of Pb doping on the structural, optical and electrical properties of sol–gel ZnO nanoparticles

Pure and Pb-doped ZnO NPs were synthesized using the sol–gel method. The structural and morphological properties were investigated via XRD, FTIR and FE-SEM. A detailed study of the effect of Pb on the properties of ZnO NPs ascertained many interesting results. XRD analysis showed that doped and undoped samples have hexagonal wurtzite structures and the average grain size increases from 21.2 to 27.8 nm with doping. Morphological analysis of undoped and Pb-doped ZnO NPs indicated that they are composed of quasi-spherical particles. Optical and electrical characteristics were also evaluated by UV–Vis spectroscopy and electrical measurements. These studies revealed that the Pb doping resulted in a blue shift of the absorption edge and thus increasing the gap band, from 3.39 to 3.53, and the electrical resistance. Based on these characteristics, the possible use of the sol–gel synthesized Pb–ZnO for conductometric gas sensing, was also discussed.

Enhancing the Photovoltaic Performance of Cd(1−x)ZnxS Thin Films Using Seed Assistance and EDTA Treatment

This research article provides a comprehensive investigation into the optoelectronic characteristics of three distinct types of cadmium sulfide (CdS) thin films, namely: (a) conventionally prepared CdS thin films using chemical bath deposition (CBD-CdS), (b) CdS thin films produced via chemical bath deposition with the inclusion of zinc (CBD-Cd(1−x)ZnxS, x = 0.3), and (c) CdS thin films synthesized using a seed-assisted approach, treated with ethylenediaminetetraacetic acid (EDTA), and incorporating zinc (ED/CBD + EDTA-Cd(1−x)ZnxS). The investigation reveals that the crystallite size of these thin films decreases upon the addition of EDTA to the reaction solution, leading to an increase in the inter-planar spacing and dislocation density. Furthermore, a blue shift in the transmittance edge of the ED/CBD + EDTA-Cd(1−x)ZnxS samples compared to CBD-CdS implies modifications in the band gaps of the deposited films. The incorporation of Zn2+ into the reaction solution results in an increased band gap value of up to 2.42 eV. This suggests that Cd(1−x)ZnxS thin films permit more efficient photon transmission compared to conventional CdS. Among the three types of films studied, ED/CBD + EDTA-Cd(1−x)ZnxS exhibits the highest optical band gap of 2.50 eV. This increase in the optical band gap is attributed to the smaller crystallite size and the splitting of the tail levels from the band structure. Additionally, the increment in the optical band gap leads to reduced light absorption at longer wavelengths, thereby enhancing the electrical properties. Notably, ED/CBD + EDTA-Cd(1−x)ZnxS thin films demonstrate improved photovoltaic performance in a photoelectrochemical (PEC) cell, characterized by enhanced open-circuit voltage (363 mV, VOC), short-circuit current (35.35 μA, ISC), and flat-band voltage (−692 mV, Vfb). These improvements are attributed to the better adhesion of CdS to the fluorine-doped tin oxide (FTO) substrate and improved inter-particle connectivity.

Visible light induced self‐cleaning performance of iron‐doped TiO2 nanoparticles for surface applications

AbstractThis study aimed to enhance the visible light photosensitivity of TiO2 nanoparticles for self‐cleaning applications by doping with Fe3+. Nanocrystalline undoped and Fe‐doped TiO2 (Ti1 − xFexO2, x = .01–.04) were synthesized via sol–gel method. The results demonstrated that Fe‐doped TiO2 nanoparticles exhibited visible light sensitivity and self‐cleaning properties. An increased Fe concentration resulted in a red shift in the absorption band edge. Fe0.03‐doped TiO2 with an average particle size of ∼21 nm, a crystallite size of ∼12 nm, and a band gap of ∼2.86 eV showed the highest photocatalytic activity (60% methylene blue degradation) and super‐hydrophilicity (water droplet contact angle 9°) under visible light radiation. These findings highlight the potential of Fe‐doped TiO2 nanoparticles as a promising material for self‐cleaning applications.

Effect of Cu ratios dopant on ZnSe thin films structural and optical properties

This study focused to prepare poly-crystalline (ZnSe)1-x Cux thin films, where x values vary from 0 to 0.1 %. the effect of Cu ratios dopant on structural, phases and optical properties has been investigated. As prepared thin films were deposited onto a cleaning glass substrate under high vacuum conditions (10-7 mbr) at room temperature using the “ evaporation technique”. The analysis results according to data of the X-ray diffraction technique of all films refer to the growth polycrystalline with hexagonal wurtzite structure of Zn-Se with no presence of any further phases. The changes in numerous parameters such as volume of the unit cell, atomic packing factor, dislocation density, lattice constant and bond length with the Cu ratio were estimated and described. As well, the crystallite sizes,D, the lattice micro-strain,ε and dislocation density,δ have been calculated the results evidence that the micro-structural parameters enhancement with increment Cu atoms. On the other hand, the optical parameters of the as-synthesized films (ZnSe)1-xCux (0 ≤ x ≤ 0.1) were performed utilizing “UV–V is spectro -photometer” with a wavelength range of 300 to 2400 nm. The results show that as the Cu ratio increases, the absorption edge shifts to a higher wavelength and the optical band gap, Eg opt decreases from 2.63 eV to 2.52 eV. Finally, the behaviour of the optical constant parameters as real,εr/ imaginary, εi parts, dissipation factor,tan δ, volume/surface energy loss functions and dispersion parameters were shown to depend on the variation of the Cu ratio and wavelengths.

Anodic Dissolution Rates Accelerate with Decreasing MoS2 Nanoflake Thickness

Electrochemical gating of 2D transition metal dichalcogenide (TMD) electrodes is an emerging frontier in the field of semiconductor electrochemistry. In this approach, an applied bias modifies the charge carrier concentration of the 2D TMD, causing band edge shifts and drastic changes in charge transfer rates. However, leveraging this effect for (photo)electrocatalysis is practically limited by the stability of the TMD material under gating conditions. Gerischer showed anodic dissolution of bulk TMD electrodes can occur in the dark and hypothesized that the reaction proceeds via an electron tunneling mechanism from surface states to the TMD conduction band [H. Gerischer, D. Ross, and M. Lubke, Z. Physickalische Chem., 139, 1 (1984)]. Here we investigate this possibility in single MoS2 nanoflakes using in situ optical microscopy and explore whether Gerischer’s electron tunneling mechanism can explain anodic dissolution rates of thin 2D semiconductors. Spatially resolved measurements show anodic dissolution initiates at perimeter edge sites and accelerates exponentially with decreasing layer thickness, consistent with Gerischer’s tunneling mechanism. Interestingly, single layer MoS2 is impervious to anodic dissolution at applied potentials >200 mV more positive than those required to drive dissolution in bulk and multilayer-thick nanoflakes.

Cationic cluster complex [{Mo6I8}(H2O)4(OH)2]2+ with diphenyl phosphate anions: Structure and optical properties behavior

The interaction of an aqueous solution of the cluster complex [{Mo6I8}(H2O)4(OH)2](NO3)2 with an excess of diphenyl phosphoric acid in ethanol leads to the formation of a light orange insoluble crystalline product. According to the single-crystal X-ray diffraction analysis, the crystals obtained have the composition [{Mo6I8}(H2O)4(OH)2]((PhO)2PO2)2·6H2O·2EtOH·2(PhO)2PO2H. The inclusion of such large molecules as diphenyl phosphate into the structure leads to a dramatic decrease in the packing density of cluster fragments. The study of the optical properties of the obtained compound showed that such a decrease in the density leads to a decrease in absorption and a hypsochromic shift of the absorption edge. At the same time, there is a significant increase in the luminescence intensity accompanied by a blueshift of the emission maximum in comparison with the initial compound and other related clusters.

Synthesis and Characterization of a Novel Nanocomposite Polymer

One-dimensional nanostructures of PANI: PVA-g-EI nanocomposite are prepared by the interfacial polymerization method. The properties of a resulting green powder are studied by the X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), and infrared spectroscopy (FTIR). Prepared thin films were characterized by UV-Vis and photoluminescence (PL) spectroscopies. The XRD pattern of the nanocomposite shows that the higher volume fraction of crystalline phases corresponds to the PANI polymer with the accepted monoclinic unit cell of PVA. Nano-sized irregular particles arranged in clusters appear in the TEM measurements and SEM images, which testifies to the agglomeration without uniform packing. EDX confirms that the PVA-g-EI is incorporated in the structure of the polymer nanocomposite. A significant shift in the absorption edge with three PL independent emission peaks again confirms that PANI/PVA-g-EI form a nanocomposite.

Studies on structural, optical and electrical behavior of La and Cr modified NaNbO3 (x ≤ 0.15)

Samples with compositions x ≤ 0.15 in the material system Na1-xLaxNb1-xCrxO3 have been prepared by conventional solid-state reaction method. Rietveld refined XRD patterns show the formation of single phase with orthorhombic (Pbcm) structural symmetry. FTIR spectra show the shifting of bands towards higher wavenumber side with dopant concentration x. UV–visible spectra show the red shift of absorption edge resulting in decrease of the band gap with x. SEM images show the decrease in the average grain size with La and Cr doping. X-Ray photoelectron spectra of a few samples have been recorded to analyze the oxidation states of various elements and oxygen vacancies estimation. Dielectric plots exhibited two anomalies, one at 404K and the other one at 610K for pure NaNbO3 over the temperature range from 300K to 773K. The high temperature dielectric anomaly at 610K for x = 0 has disappeared for higher x and dispersion above 500K becomes more prominent. Tanδ with temperature plots show almost two anomalies for x = 0 which seems to be disappeared with increasing x. The conductivity is found to increase with increasing dopant concentration.

A first-principles study on the electronic and optical properties of ZnO nanowires toward detection of α-amino acids

In this paper, ab initio calculations for the adsorption of six prevalent alpha-amino acids, as metabolite biomarkers, onto the zinc oxide nanowire (ZnONW) are accomplished by applying the SIESTA package. This study aims to assay the electronic and optical properties of the α-amino acid-adsorbed ZnONWs comparatively. The species of interest contain arginine, asparagine, cysteine, glycine, lysine, and proline as repetitive monomers in human cells. Representation of total and local density of states reveals strong chemisorption of the α-amino acids from the carboxylic end with the nanowire through n-type conduction in conjunction with the adsorption energy of lower than −0.816 eV and charge transfer of higher than 0.238 |e|, respectively. In particular, highly polarizable cysteine-adsorbed ZnONW with the maximum difference in isoelectric point of ZnO and cysteine shows the highest corresponding quantities equal to −2.825 eV and 0.543 |e|, respectively. In comparison with the pristine ZnONW, the higher the amount of charge transferred in α-AA-adsorbed ZnONW, the larger the shift in the conduction band edge to the lower energies. The calculation of the absorption coefficient for the α-amino acid-adsorbed ZnONWs implies the presence of an enhanced peak within the near-UV spectrum for the carboxyl-oriented arginine-, lysine-, and proline-ZnONW complexes, in addition to an attenuated peak within the visible spectrum for the carboxylic/thiol-oriented cysteine-ZnONW configuration. Subsequently, it is revealed that jointly exploring both electronic and optical properties of the specific cysteine-adsorbed nanowires is of utmost importance, which could provide further evidence for the early prognosis of cystinuria and other associated metabolic disorders.

Failure mechanism of rock specimens with an elliptical pre-hole under different stress conditions

This paper conducted a load test on rock specimens containing an elliptical pre-hole using a combination of numerical simulation and theoretical solutions of linear elasticity. The aim is to investigate the impact of elliptical geometric parameters and stress conditions on the rock failure process while considering a consistent hole area. Additionally, laboratory experiments incorporating digital image correlation (DIC) techniques were used for verification. This result indicates that the impact of elliptical geometric parameters is primarily observed during the early stage of loading, while it has minimal influence on the deterioration effect and failure mode of rock specimens during the later stage of loading. Regarding the inclination angle, as its value increases, the pure tension region near the hole diminishes, and the failure point on the hole's edge shifts from the coordinate axis direction to the inclination direction before returning to its original direction. Regarding the axis ratio, as the value decreases, the pure tension region diminishes at small angles, while the opposite occurs at large angles. Confining pressure affects the whole loading process. The greater the confining pressure, the smaller the tensile stress in the rock specimen, the more the tensile failure mode is suppressed, and the larger the rock specimen strength is.

Effect of iodine on physicochemical and optical properties of Ge20Te77-xSe3Ix (x = 0–10) glasses

Thermodynamic modeling of the Ge-Te-I system is carried out. The dependences of the equilibrium concentrations of components in the condensed and vapor phases on temperature and iodine content are established. The compositional effect on the properties of Ge20Te77-xSe3Ix (x = 0–10) and Ge20Te72-ySeyI8 (y = 1, 3, 5) glasses is studied. In the glasses, with an increase in the iodine content, the glass transition temperature decreases, the stability against crystallization increases, and the short-wavelength transparency edge shifts towards shorter wavelengths. Selenium increases the stability of glasses against crystallization and limits transparency in the long-wavelength spectral range. The Ge20Te69Se3I8, Ge20Te67Se5I8, and Ge20Te67Se3I10 compositions are potentially suitable for fabricating optical fibers. The Ge20Te69Se3I8 glass sample with an oxygen impurity content chemically bonded with germanium of less than 50 ppb(wt) and low absorption in the 3–18 μm spectral range is prepared.