Effect Of Tin Doping Research Articles

Effect of tin doping on the structural, optical, and dielectric properties of unintentionally β-Ga2O3 single crystal

This paper studied the structural, optical, electrical, and dielectric properties of the undoped and 0.05 mol% Sn-doped β-Ga2O3 single crystals through comprehensive characterizations by x-ray diffraction (XRD), Raman scattering, Optical transmittance spectroscopy, x-ray photoelectron spectroscopy (XPS), Ultraviolet photoelectron (UPS) spectroscopy, and dielectric measurements. The optical bandgap decreases as Sn content increases. The results of XPS showed that Sn atoms were successfully added to the host β-Ga2O3 crystal. The position of the Fermi level of 0.05 mol% Sn-doped β-Ga2O3 is calculated to be 2.56 eV above the valence band and 1.85 eV beneath the conduction band. Also, the computed value of the work function of 0.05% mole Sn-doped β-Ga2O3 is 4.53 eV. AC conductivity increases, while dielectric loss and dielectric constant decrease with increasing frequency.

Effect of tin doping and tin-bromine co-doping on electronic and optical properties of BiOCl crystal: density functional theory

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 effect of tin doping on the band structure and optical properties of polycrystalline antimony selenide

In this study, we investigated the effect of Sn-doping on the antimony selenide (Sb2Se3) polycrystalline material to alter its optical properties and electronic band structure. Sb2Se3 polycrystals were isothermally annealed at 350 °C, 400 °C, 450 °C, and 500 °C, in the presence of tin diselenide (SnSe2) in degassed quartz ampoules to introduce Tin (Sn) into the material. X-ray diffraction (XRD), Raman scattering, and energy-dispersive X-ray spectroscopy measurements confirmed the single phase of the Sb2Se3 samples. Successful doping of the surface of the Sb2Se3 polycrystals with Sn was confirmed by X-ray photoelectron spectroscopy for the samples annealed at 400 °C, 450 °C, and 500 °C in the presence of SnSe2. An ultraviolet photoelectron spectroscopy (UPS) study revealed a decrease in the work function (Ф) of the Sb2Se3 polycrystals from 4.34 eV to 3.14 eV due to Sn doping implemented at 500 °C. Moreover, a small shift of the Fermi level towards the valence band maximum (VBM) by 30 meV resulted from Sn-doping at 500 °C as was detected by UPS, indicating a slightly enhanced p-type behaviour of the surface region of the Sb2Se3 polycrystals. Ultraviolet–visible spectroscopy (UV–Vis) confirmed that Sn doping did not change the bandgap energy of Sb2Se3 polycrystals, being 1.25 eV at room temperature (RT) for the undoped as well as Sn-doped material.

Effect of tin doping on optical properties of ZnO thin films grown on glass substrate

The optical properties of synthesized zinc oxide films doped with tin in different concentrations (0-5 mol.%) were studied. X-ray diffraction revealed that the main phase of the obtained films is ZnO (wurzite). According to SEM data, the film consists of nanocrystallites, which are 10-20 nm in size. It was shown that the introduction of 0.5 mol.% tin ions leads to an increasing in the absorption of wavelengths (in the range of 300-370 nm) and a slight narrowing of the band gap.

Physical properties and ethanol response of sprayed In2S3:Sn films

Tin-doped indium sulfide (In2S3:Sn) thin films were deposited on the glass substrate by varying molar ratio of Sn:In from 0 to 4% using spray pyrolysis. X-ray diffraction analysis showed that the deposited films were polycrystalline and crystallized in a cubic structure. The evaluated crystallite size varied in the range, 14.8–25.5 nm. The root-mean-square (RMS) roughness values decreased from 39 to 17 nm. Raman studies showed different peaks related to In2S3 phase and no additional phase was detected. The optical analysis allowed us to know that In2S3:Sn thin films had a transparency over 65%–70% in the visible region and 75%–90% in the near-infrared region. It displayed a band gap from 2.68 to 2.91 eV for the direct transition. The refractive index (n) values of In2S3:Sn thin films decreased from 2.45 to 2.37. The extinction coefficient (k) values were in the range of 0.01–0.21. Effect of tin doping on ethanol sensing response was also investigated. A slight enhancement in response is shown for In2S3:1%Sn sample.

Structural, optical, and electrical modification of hydrothermally grown ZnO nanorods by tin-doping

ZnO nanorod has been a material of interest in numerous electronic applications. Here, ZnO nanorods were grown on a fluorine doped tin oxide (FTO) coated glass substrate with a spray-pyrolysis deposited seed layer via a low-temperature hydrothermal method, and the effects of tin-doping on structural formation, optical and electrical properties were explored. The XRD result confirmed the formation of ZnO wurtzite phase without secondary phases; however, the different preferential growth orientations were observed as tin dopants were added. The result was consistent with the surface morphology examined by SEM showing that the ZnO nanorod structure was likely to become a plate-like structure when Sn content increased. Moreover, increasing Sn doping content also resulted in a blue shift in bandgap energy and electrical conductivity enhancement. The results suggest that the incorporation of Sn ion in the ZnO structure can tailor its preferential growth orientation and morphology potentially leading to the performance improvement of electronic devices.

Effects of tin-doping on cadmium sulfide (CdS:Sn) thin-films grown by light-assisted chemical bath deposition process for solar photovoltaic cell

Thin transparent films of tin-doped cadmium sulfide (CdS) on different substrates were obtained by an ammonia-free chemical bath deposition technique assisted by ultraviolet illumination with a wavelength of 265 nm. Several sets of films were deposited by varying the amount of SnCl2 in the reaction bath and analyzed by X-ray diffraction, scanning electron microscopy, optical transmission and reflection spectroscopy and current versus voltage measurements. In the doped films, the position of the main X-ray diffraction peak is shifted to larger angles showing a decrease of the crystal lattice constant; this is attributed to the substitution of tin by cadmium in the doping process. The morphological characterization of the doped films shows homogeneously distributed spherical grains with an average grain size of 58.5 nm. The grains are composed of crystallites with an average size of 23 nm; the surface of the doped films does not show conglomerates that are typical for materials grown by the chemical bath deposition technique. The electrical properties reveal a decrement in the resistivity of an order of magnitude with respect to the films without doping. The optical results exhibit variation in the band gap that we consider as the consequence of the films' porosity; the theoretical analysis presented confirms this point. The films show a reflectance at a normal incidence less than 30%, which is an indication of their good optical quality. The main effects of the tin doping on the CdS films were observed as changes in the crystal structure and electrical resistivity.

Optical, Physical, Chemical and Electrical Properties of Nickel Oxide Sprayed Thin Films under Tin Doping Effects

Tin-doped nickel oxide thin films have been successfully prepared by spray pyrolysis technique on glass substrates at 460°C. The effects of tin doping on structural, optical, and electrical properties were investigated. X-ray diffraction pattern reveals that all prepared thin films have cubic structure with (111) preferred orientation. The surface topography of these films was performed by atomic force microscopy. Optical measurements show a high transparency in the visible range around 95%. The optical band gap Eg decreases with Sn content from 3.633 to 3.54 eV. PL measurements show some bands transition which shift irregularly with Sn doping. Finally, the electric conductivity of NiO thin film was investigated through the impedance spectroscopy measurements in the frequency range 5 Hz-13 MHz at various temperatures. These measurements show a thermally activation of the electric. AC conductivity of NiO thin films is investigated through Jonscher law. Also, from these measurements, dielectric parameters were calculated.

Effect of tin doping on optical properties of nanostructured ZnO thin films grown by spray pyrolysis technique

Sn-doped ZnO thin films with 0%, 0.5%, 1%, 1.5% and 2% Sn were grown by spray pyrolysis method on glass substrates under optimized conditions. High resolution Field Effect Scanning Electron Microscopy characterization showed that the films consist of hexagonal-like grains. A comprehensive study of the optical properties was performed and the dispersion constants were determined. The effect of Sn content on the optical band gap and the optical constants (refractive index, extinction coefficient, dielectric constants, and dispersion parameters) was studied. These Sn-doped ZnO thin films are highly transparent (73–93%) in the visible region. A blue shift of the optical band gap, attributed to the Burstein Moss effect, was observed for the Sn-doped films. All the optical dispersion parameters depend on the Sn content of the films, but were found to reach threshold values at a Sn content of 0.5%. These optical parameters are discussed in terms of the single oscillator model. This study demonstrated that this 0.5% Sn-doped ZnO thin film has enhanced physical properties, allowing its better integration in optoelectronic devices.

Preparation of Sn-doped 2–3 nm Ni nanoparticles supported on SiO2 via surface organometallic chemistry for low temperature dry reforming catalyst: The effect of tin doping on activity, selectivity and stability

Silica supported nickel nanoparticles of 2.2±0.4nm diameter were selectively doped with tin by surface organometallic chemistry while keeping the particle size nearly constant. The catalysts with various tin contents were doped and characterized by TEM, XRD and H2 chemisorption. In contrast to what is found at high temperature (≥973K), dry reforming tests performed at 773K and successive TPO and TEM analysis showed that tin neither influences the catalyst deactivation rate nor prevents coke formation, present in the form of encapsulating carbon. The nickel dopant does not influence either the selectivity, ruled by reverse water gas shift Thermodynamics, but was shown to have a 3–4-fold decrease of intrinsic activity of the available surface nickel, thus indicating that Sn has a negative effect on adjacent Ni atoms.

Tin induced a-Si crystallization in thin films of Si-Sn alloys

Effects of tin doping on crystallization of amorphous silicon were studied using Raman scattering, Auger spectroscopy, scanning electron microscopy, and X-ray fluorescence techniques. Formation of silicon nanocrystals (2–4 nm in size) in the amorphous matrix of Si1−xSnx, obtained by physical vapor deposition of the components in vacuum, was observed at temperatures around 300 °C. The aggregate volume of nanocrystals in the deposited film of Si1−xSnx exceeded 60% of the total film volume and correlated well with the tin content. Formation of structures with ∼80% partial volume of the nanocrystalline phase was also demonstrated. Tin-induced crystallization of amorphous silicon occurred only around the clusters of metallic tin, which suggested the crystallization mechanism involving an interfacial molten Si:Sn layer.

Effects of Tin Doping on the Physical Properties of Thermally Deposited Sb2S3 Thin Films

Tin doped antimony sulfide thin films have been grown on glass substrates at room temperature by vacuum thermal evaporation method. The doping was carried out during the growth by two source method with the aim to investigate its effects on electrical, structural and optical properties of 1, 2 and 3 wt.% Sn-doped Sb2S3 thin films. Using transmission spectra in the range of 200-1800 nm, the absorption coefficient of the deposited films in the fundamental absorption edge has been analyzed to identify the possible optical transition in these films, where the energy band gap corresponding to the optical transition is calculated. Hot point probe method has been used to study the conductivity type and photoconductivity values of the thin films in the wavelength range 380-1100 nm of the incident photons. Effects of doping on external quantum efficiency (EQE) are also investigated. Keywords: Tin antimony sulfide, thin film, electrical and structural properties.

Photocatalytic activity of tin-doped TiO2 film deposited via aerosol assisted chemical vapor deposition

Tin-doped TiO2 films are deposited via aerosol assisted chemical vapor deposition using a precursor mixture composing of titanium tetraisopropoxide and tetrabutyl tin. The amount of tin doping in the deposited films is controlled by the volume % concentration ratio of tetrabutyl tin over titanium tetraisopropoxide in the mixed precursor solution. X-ray diffraction analysis results reveal that the as-deposited films are composed of pure anatase TiO2 phase. Red-shift in the absorbance spectra is observed attributed to the introduction of Sn4+ band states below the conduction band of TiO2. The effect of tin doping on the photocatalytic property of TiO2 films is studied through the degradation of stearic acid under UV light illumination. It is found that there is a 10% enhancement on the degradation rate of stearic acid for the film with 3.8% tin doping in comparison with pure TiO2 film. This improvement of photocatalytic performance with tin incorporation could be ascribed to the reduction of electron-hole recombination rate through charge separation and an increased amount of OH radicals which are crucial for the degradation of stearic acid. Further increase in tin doping results in the formation of recombination site and large anatase grains, which leads to a decrease in the degradation rate.

Effect of tin doping on oxygen- and carbon-related defects in Czochralski silicon

Experimental and theoretical techniques are used to investigate the impact of tin doping on the formation and the thermal stability of oxygen- and carbon-related defects in electron-irradiated Czochralski silicon. The results verify previous reports that Sn doping reduces the formation of the VO defect and suppresses its conversion to the VO2 defect. Within experimental accuracy, a small delay in the growth of the VO2 defect is observed. Regarding carbon-related defects, it is determined that Sn doping leads to a reduction in the formation of the CiOi, CiCs, and CiOi(SiI) defects although an increase in their thermal stability is observed. The impact of strain induced in the lattice by the larger tin substitutional atoms, as well as their association with intrinsic defects and carbon impurities, can be considered as an explanation to account for the above observations. The density functional theory calculations are used to study the interaction of tin with lattice vacancies and oxygen- and carbon-related clusters. Both experimental and theoretical results demonstrate that tin co-doping is an efficient defect engineering strategy to suppress detrimental effects because of the presence of oxygen- and carbon-related defect clusters in devices.

Effects of tin doping on physicochemical and electrochemical performances of LiFe 1− xSn xPO 4/C (0 ≤ x ≤ 0.07) composite cathode materials

Nanocrystalline LiFe 1− x Sn x PO 4 (0 ≤ x ≤ 0.07) samples are synthesized using SnCl 4·5H 2O as dopant via an inorganic-based sol–gel method. The dependency of the physicochemical and electrochemical properties on the doping amount of tin are systemically worked out and regular changes are revealed. In the whole concentration range, the chemical valence of Fe 2+ is not basically changed whereas tin is found in two different oxidation states, namely +2 and +4. The replacement of Fe 2+ by supervalent Sn 4+ would lead to electron compensation. Under the synergetic effects between the charge compensation and the crystal distortion, the electrical conductivities for the bulk samples first increase and then decrease with the increasing amount of Sn doping. Upon the doping amount, the apparent lithium-ion diffusion coefficient and the electrochemical performance also display the similar trends. The doping is beneficial to refine the particle size and narrow down the size distribution, however optimizing the doping amount is necessary. Compared with other samples, the sample with a doping amount of about 3 mol% delivers the highest capacities at all C-rates and exhibits the excellent rate capability due to the high electrical conductivity and the fast lithium-ion diffusion velocity.

Hydrogen Production by Glycerol Steam Reforming with Ru‐based Catalysts: A Study on Sn Doping

AbstractBimetallic Ru‐Sn heterogeneous catalysts for glycerol steam reforming (SR) to hydrogen‐rich mixtures are developed using organometallic (OM)CVD of commercial metal precursors as the preparation technique of choice. This methodology produces monometallic Ru nanoparticles (NPs) supported on Mg(Al)O mixed oxide with high activity and selectivity for glycerol SR. The effect of tin doping is studied on a set of catalysts with various Sn loadings. Materials produced are characterized by high resolution transmission electron microscopy (HRTEM) and by diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)‐quadrupole mass spectrometry (QMS) of adsorbed CO and tested in glycerol SR.At low load, tin is almost selectively deposited on Ru NP faces, and resulting Ru‐exposed sites show a higher specific activity than Ru exposed sites in monometallic catalysts.

Effect of tin level on particle size and strain in nanocrystalline tin-doped indium oxide (ITO)

A series of Sn-doped In2O3 samples, with doping levels of 0, 2.1, 4.0, 6.0, 7.8, 9.7, 11.1 and 12.3 at% Sn, has been prepared by a sol-gel technique. The effect of tin doping on microstructure of the samples has been investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Diffraction patterns indicated that all samples were cubic, space group Ia-3, and isostructural with In2O3. Diffraction lines were broadened, the line broadening increased with tin doping level. Analysis of line broadening was performed by the Rietveld refinement of XRD patterns, using silicon powder as an external standard for instrumental diffraction-line broadening. The crystallite size decreased with tin doping level, from 25.5(1) nm for undoped In2O3 sample to 16.8(1) nm for sample doped with 12.3 at% Sn. Simultaneously, the lattice strain increased from 0.112(6)% for undoped sample to 0.369(9)% for 12.3 at% Sn. TEM investigations confirmed that the samples were nanocrystalline, having a cubic structure characteristic for In2O3. Interplanar distances, d, of the samples determined by the selected area electron diffraction (SAED) were in agreement with those obtained by XRD. Particles in the samples had nearly spherical shape at lower tin doping level (< 6.0 at% Sn). At higher doping level they were slightly elongated. The particle sizes in the samples as determined by TEM followed the behavior of crystallite sizes obtained by XRD line broadening analysis.

Effect of tin doping on the properties of indium-tin-oxide films deposited by radio frequency magnetron sputtering

Indium-tin-oxide doped tin films were prepared by magnetron sputtering under various sputtering power of tin target and various post-annealing temperatures. Experimental results show that the carrier concentration of these films increased with the doping of tin, although, the mobility of the carrier decreased. When the sputtering power of tin target is 7.5 W, there is maximum carrier mobility of 32.1 cm 2 s V −1 and lowest resistivity of 6.92 × 10 −4 Ω cm. After annealing, an electrical resistivity as low as 2.67 × 10 −4 Ω cm was obtained. The optical transmittance of films in visible region increased over 90% after annealing. The optical energy band gap increased with the increase of the annealing temperature and the optical band gap is 3.96 eV at 450 °C.

Transparent conductive Sn-doped indium oxide thin films deposited by spray pyrolysis technique

Films of indium oxide doped with tin (ITO) are prepared using the low cost spray pyrolysis technique. The effect of tin doping on the physical properties of In2O3 are studied. In this study the polycrystalline ITO films with the different Sn concentration of 1 to 100-wt% SnCl2 were prepared on Corning 7059 glass substrate. These films were confirmed to show the high crystallinity by X-ray diffraction technique. Low sheet resistance (25Ω/■) and high visible transmission (~82%) were obtained when the films were deposited at the tin concentration of 2-wt%.

Neutron diffraction study on the defect structure of indium–tin–oxide

The defect structure of undoped and Sn-doped In2O3 (ITO) materials was studied by preparing powders under different processing environments and performing neutron powder diffraction. The effect of tin doping and oxygen partial pressure was determined. Structural information was obtained by analyzing neutron powder diffraction data using the Rietveld method. The results include positions of the atoms, their thermal displacements, the fractional occupancy of the interstitial oxygen site, and the fractional occupancies of Sn on each of the two nonequivalent cation sites. The tin cations show a strong preference for the b site versus the d site. The measured electrical properties are correlated with the interstitial oxygen populations, which agree with the proposed models for reducible (2SnIn•Oi″)x and nonreducible (2SnIn•3OOOi″)x defect clusters.