Effect Of Sb Doping Research Articles

Study of Antimony and Fluorine Doped Tin Oxide in Acidic Medium

In recent decades, the high-energy demand has generated interest in renewable energies and has become a more pressing issue for the development of cost-effective and eco-friendly conversion and storage technologies.1 Solar conversion systems are very attractive to address this problem, either in photovoltaic systems or in systems that store solar energy in chemical form ("solar fuels").2-3 However, there are challenges in terms of functionality, such as (1) finding suitable materials for photon absorption and (2) developing materials for the water electrolysis reaction to produce hydrogen as a solar fuel.4 Materials include catalysts and catalyst supports that allow a stable operation of a cell. Sb-doped tin oxide (ATO) has recently been used as an electrocatalyst support under acidic conditions and proposed as an alternative to F-doped tin oxide (FTO). In this talk, we will address our studies in acidic media of the fundamental electrochemistry of ATO to determine the potential window corresponding to the operation of the material in acid solutions. Experimental. The experiments were performed in a 3-electrode cell. A glassy carbon electrode of 0.0706 cm2 surface area was used as working electrode (WE), a graphite rod of 0.618 cm diameter as counter electrode (CE), and an Ag/AgCl as reference electrode (RE). The RE was placed in a double junction, and the electrolyte used was a 0.5 M H2SO4 solution (Ultrex® II Ultrapure Reagent). Electrochemical measurements were made on a CH instruments electrochemical workstation potentiostat (CHI 760D). Open circuit potential (OCP) and cyclic voltammograms (CV) were collected. The electrolyte was deoxygenated with Ar, and an Ar blanket was kept on top of the electrochemical cell surface.Cavaliere and coworkers had synthesized an antimony-doped tin oxide (ATO) with microwaves5 and carried out different studies regarding the applications of ATO as support toward proton-exchange membrane fuel cell (PEMFC)6. Our studies of ATO were mainly focused on the electrochemical activity of anodic potentials. Figure 1 shows two oxidation peaks: one at 0.147 V and the other at -0.253 V both vs NHE. We have assigned the peak at 0.147 V to tin dissolution because of the potentials for SnO2 reduction:7 The material exhibits a potential window of more than one volt in acidic media, which we propose corresponds to the thermodynamic stability of ATO. The anodic and cathodic limits, and the effect of Sb doping on the SnO2 material will be discussed in detail in the presentation. Acknowledgment The authors express their gratitude to the National Science Foundation (NSF) for the financial support through NSF project CHE-2108462. References Zhao, Y.; Adiyeri Saseendran, D. P.; Huang, C.; Triana, C. A.; Marks, W. R.; Chen, H.; Zhao, H.; Patzke, G. R., Oxygen Evolution/Reduction Reaction Catalysts: From In Situ Monitoring and Reaction Mechanisms to Rational Design. Chemical Reviews 2023.Bordet, A.; Leitner, W., Adaptive Catalytic Systems for Chemical Energy Conversion. Angewandte Chemie International Edition 2023, 62 (33), e202301956.Bagdanavicius, A., Energy and Exergy Analysis of Renewable Energy Conversion Systems. Energies 2022, 15 (15), 5528.Montoya, J. H.; Seitz, L. C.; Chakthranont, P.; Vojvodic, A.; Jaramillo, T. F.; Nørskov, J. K., Materials for solar fuels and chemicals. Nature Materials 2017, 16 (1), 70-81.Cavaliere, S.; Subianto, S.; Savych, I.; Tillard, M.; Jones, D. J.; Rozière, J., Dopant-Driven Nanostructured Loose-Tube SnO2 Architectures: Alternative Electrocatalyst Supports for Proton Exchange Membrane Fuel Cells. The Journal of Physical Chemistry C 2013, 117 (36), 18298-18307.Dubau, L.; Maillard, F.; Chatenet, M.; Cavaliere, S.; Jiménez-Morales, I.; Mosdale, A.; Mosdale, R., Durability of Alternative Metal Oxide Supports for Application at a Proton-Exchange Membrane Fuel Cell Cathode—Comparison of Antimony- and Niobium-Doped Tin Oxide. Energies 2020, 13 (2), 403.Bard, A. J. P., R; Jordan, J. , Standard Potentials in Aqueous Solution. 1st edition ed.; CRC Press, 1985: 1985; Vol. Volume 6 of Monographs in Electroanalytical Chemistry and Electrochemistry, p 848. Figure 1

Morphological Characterization of Sb-Doped SnO2 Thin Films Developed by Spray Pyrolysis

In the present work, we have successfully deposited Sb antimony doped tin dioxide (SnO2) thin films with different concentrations (0 at%, 1 at%, 3 at% and 5 at%) from a stannous (II) chloride dihydrate solution (SnCl2.2H2O), by the pyrolysis chemical spray deposition technique on ordinary microscope glass substrates preheated to a fixed temperature of 350 °C. After deposition, the films were annealed at temperatures 400 °C for 4h. The aim of this work is on the one hand to study the morphological properties of pure and doped tin dioxide thin films and to determine the different morphological parameters such as: the roughness Ra, Rq and on the other hand to study the effect of Sb doping on the morphological properties of SnO2 thin films. To achieve this purpose, the thickness of all the films was estimated by profilometer with standard scan type. The morphology of the films was examined by atomic force microscope (AFM) in contact mode at room temperature to visualize the surface of our samples (the structure, size and morphology of crystallites ... etc). The 2D and 3D AFM images confirm the formation of nanostructures on the surface, with shapes and dimensions influenced by the amount of antimony doping. All the samples show a polycrystalline morphology, and the grain size progressively decreases with the increase of the Sb concentration (1% and 3%). On the other hand, for high antimony doping (5% Sb) the grains are larger than those observed at 3% doping. The root mean square (RMS) surface roughness values for samples with Sb concentrations (5%) were found to be 8.334 nm.

Enhanced physical properties of stable lead-free oxide double perovskite Ba2TbBiO6 for photovoltaics: Effects of Sb doping

The effect of Sb-doping in the Bi-based double perovskite Ba2TbBi1-xSbxO6(x = 0.0, 0.5) on providing a structural and electronic framework for understanding numerous physical aspects at an atomistic level. We study in detail the undoped and Sb-doped Ba2TbBiO6 double perovskite’s structural, elastic, mechanical, electronic, and thermodynamic properties for both cubic and monoclinic phases. Doping alters the spatial group structure and lattice constant of Ba2TbBi1−xSbxO6, causing a change in the Brillouin zone, which alters the band structure and bandgap value. The elastic constants confirmed the ductility of the solids and ensured mechanical stability in both phases. This study reveals that both phases of Ba2TbBi1−xSbxO6 are more mechanically stable, ductile, and machinable than Ba2TbBiO6. The Sb-doped monoclinic phase had greater anisotropy than the cubic phase, despite the fact that both phases were anisotropic. Vickers hardness shows that the monoclinic Ba2TbBi1−xSbxO6(x = 0.0, 0.5) phase is harder than the cubic Ba2TbBi1−xSbxO6(x = 0.0, 0.5) phases. The cubic and monoclinic phases of Ba2TbBi0.5Sb0.5O6 have Debye temperatures of 248.48 and 240.75 K, respectively. After doping, the cubic phase’s melting temperature (1529.21 K) grows higher than that of the monoclinic phase (1386.87 K). Doping can make a material more stable by lowering its thermal expansion coefficient. Both doped phases can be used as thermal barrier coatings (TBCs).

Enhanced performance of proton exchange membrane fuel cells by Pt/carbon/antimony-doped tin dioxide triple-junction catalyst

A composite material comprising carbon black and Sb-doped SnO2 (ATO) is employed as a support for a Pt catalyst in a membrane electrode assembly (MEA) to improve the performance of a proton-exchange membrane fuel cell under low-humidity conditions. The effects of Sb-doping on the crystal, structural, and electrochemical characteristics of ATO particles are being examined. In a single cell test, the ratio of Sb in ATO is systematically optimized to improve performance. The distribution of Pt nanoparticles is uniform on carbon black and ATO carrier, forming notable triple-junction points at the interface of carbon black and ATO carrier. This structure thus induces a strong interaction between Pt and ATO, promoting the content of metallic Pt. Compared with a Pt/C catalyst, the best-performing Pt/C–ATO catalyst exhibits superior electrochemical activity, stability, and CO tolerance. The power density of MEA with the Pt/C–ATO catalyst is 15% higher than that of the MEA with the Pt/C catalyst

Effect of Sb Doping on Structure and Humidity Sensing Properties of SnO2 Synthesized by Hydrothermal Method

AbstractThe tetragonal rutile Sb doped Sn O2 (0, 0.5, 1 at.%) is successfully synthesized by hydrothermal method. The XRD analysis shows that the average crystallite size of SnO2 decreases from 29.59 to 20.53 nm with the increase of the doping concentration. SEM images depict the spherical grain morphology of the SnO2 sample. With the increase of the doping ratio, the optical bandgap value of the SnO2 samples increases from 3.6 to 3.86 eV and then decreases to 3.47 eV, showing a trend of first increasing and then decreasing. XPS results indicate that oxygen vacancy defects and substitutional defects(SbSn)are formed into the SnO2 lattice, which changes the electronic effect of Sn element to tune the oxygen vacancy concentration. The humidity‐sensitive testing data shows that 1 at.% Sb‐doped SnO2 humidity sensor presented excellent sensitivity and linearity at a working frequency of 100 Hz as compared to the pure SnO2 sample.

Effects of Sb doping on the electrical characteristics of Ta-doped SnO2 varistors

This article describes the combined mixture of antimony and tantalum in SnO2 varistors. The results show that a moderate level of antimony can reduce the grain resistivity and maintain a high voltage gradient while providing good nonlinearity. The best electrical properties were obtained by doping 0.5 mol% antimony pentoxide and 0.003 mol% tantalum pentoxide. The nonlinear coefficient of 51, the leakage current of 5.7 μA/cm2, the voltage gradient of 480 V/mm and the grain resistance of 5.0 Ω.

Room‐Temperature High‐Performance Thermoelectric Bi0.6Sb0.4Te: Elimination of Detrimental Band Inversion in BiTe

AbstractRoom‐temperature thermoelectric materials are the key to miniaturizing refrigeration equipment and have great scientific and social implications, yet their application is hindered by their extreme scarcity. BiTe exhibiting strong spin‐orbit coupling peaks ZT at 600 K. Herein, we discover the synergy effect of Sb doping in BiTe that eliminates the detrimental band inversion and leads to an overlap of conduction band (CB) and valence band that significantly increases the S from 33 to 124 μV K−1. In addition, this effect enhances the μ from 58 to 92 cm2 V−1 s−1 owing to the sharp increase in the CB slope along the Γ‐A in the first Brillouin zone. Furthermore, Sb doping increases the anharmonicity, shortens the phonon lifetime and lowers κlat. Finally, Se/Sb codoping further optimizes the ZT to 0.6 at 300 K, suggesting that Bi0.6Sb0.4Te1−ySey is a potential room‐temperature TE material.

Room-Temperature High-Performance Thermoelectric Bi0.6 Sb0.4 Te: Elimination of Detrimental Band Inversion in BiTe.

Room-temperature thermoelectric materials are the key to miniaturizing refrigeration equipment and have great scientific and social implications, yet their application is hindered by their extreme scarcity. BiTe exhibiting strong spin-orbit coupling peaks ZT at 600 K. Herein, we discover the synergy effect of Sb doping in BiTe that eliminates the detrimental band inversion and leads to an overlap of conduction band (CB) and valence band that significantly increases the S from 33 to 124 μV K-1 . In addition, this effect enhances the μ from 58 to 92 cm2 V-1 s-1 owing to the sharp increase in the CB slope along the Γ-A in the first Brillouin zone. Furthermore, Sb doping increases the anharmonicity, shortens the phonon lifetime and lowers κlat . Finally, Se/Sb codoping further optimizes the ZT to 0.6 at 300 K, suggesting that Bi0.6 Sb0.4 Te1-y Sey is a potential room-temperature TE material.

Detection of ammonia gas at room temperature through Sb doped SnO2 thin films: Improvement in sensing performance of SnO2

This paper presents the effects of Sb doping on the gas-sensing properties of SnO2 thin films prepared through a nebulizer-assisted spray pyrolysis technique. An improvement in the inherent characteristics of the transparent conducting oxide after 0 to 5 wt% Sb doping is reported. The deposited films were used to sense the presence of 50 to 250 ppm of ammonia at room temperature. Various analytical techniques were used to analyze the properties of the Sb-doped SnO2 films. X-ray diffraction spectra revealed the tetragonal structure of crystallites, and the maximum crystallite size was observed in the 2-wt%-Sb-doped SnO2 film. The morphological images showed spherical grains in pristine SnO2 films and their transformation to a trigonal shape after Sb doping; particularly, a large grain size was observed at 2 wt% doping. PL studies of the materials revealed that a large number of oxygen vacancies exist in the 2-wt%-Sb-doped SnO2 thin film. The transmittance of the films remained at approximately 75%, and the band gap varied from 3.94 to 4.01 eV as the doping concentration varied from 1 to 5%. A high response of 138% was observed for 250 ppm of ammonia in the case of the 2-wt%-Sb-doped SnO2 film, with a 42 s response time and a 11 s recovery time. Thus, the 2-wt%-Sb-doped SnO2 thin film has suitable characteristics for application as an efficient gas sensor to detect ammonia.

A High-Rate, Durable Cathode for Sodium-Ion Batteries: Sb-Doped O3-Type Ni/Mn-Based Layered Oxides.

O3-Type layered oxides are widely studied as cathodes for sodium-ion batteries (SIBs) due to their high theoretical capacities. However, their rate capability and durability are limited by tortuous Na+ diffusion channels and complicated phase evolution during Na+ extraction/insertion. Here we report our findings in unravelling the mechanism for dramatically enhancing the stability and rate capability of O3-NaNi0.5Mn0.5-xSbxO2 (NaNMS) by substitutional Sb doping, which can alter the coordination environment and chemical bonds of the transition metal (TM) ions in the structure, resulting in a more stable structure with wider Na+ transport channels. Furthermore, NaNMS nanoparticles are obtained by surface energy regulation during grain growth. The synergistic effect of Sb doping and nanostructuring greatly reduces the ionic migration energy barrier while increasing the reversibility of the structural evolution during repeated Na+ extraction/insertion. An optimized NaNMS-1 electrode delivers a reversible capacity of 212.3 mAh g-1 at 0.2 C and 74.5 mAh g-1 at 50 C with minimal capacity loss after 100 cycles at a low temperature of -20 °C. Such electrochemical performance is superior to most of the reported layered oxide cathodes used in rechargeable SIBs.

Effects of Sb Doping on Electrical Conductivity Properties in Fine-Grain KNN-Based Ferroelectric Ceramics

In this work, the effects of Sb doping on the electrical conductivity of fine-grain 0.9(K0.5Na0.5)(Nb1−xSbx)O3-0.1Bi(Ni2/3Nb1/3)O3 (KNNSx-BNN) ceramics were systemically investigated. It was found that the grain size decreases from ~900 nm (x = 0) to ~340–400 nm (x = 0.06–0.08), and then increases again to ~700 nm (x = 0.10). This is because the solubility limit of Sb doping is about 0.08 in this ceramic, and more Sb doping will facilitate the grain growth as the sintering aids. Impedance and conductivity analyses reveal that the grain resistance and its activation energy show a similar changing tendency with grain size, while grain boundary conductivity steadily increases after Sb doping. In this process, the grain contribution on ceramic conductivity changes with grain size variation, and grain boundary contribution becomes more obvious with increasing doping content. The reduction in grain size, improvement in grain boundary density and doping ions entering into the grain boundary should contribute to the evolution of electrical conductivity properties after Sb doping in KNN-based ferroelectric ceramics.

Effects of Sb-doping on the grain growth of CIGS thin films fabricated by electrodeposition

Effects of Sb-doping on the grain growth of CIGS thin films fabricated by electrodeposition

Investigation on the Role of antimony in CdTe QDs sensitized solar cells

In this work, the effect of Sb doping on the structural, optical and photovoltaic properties of the CdTe quantum dots (QDs) were reported. Sb doped CdTe (SDC) QDs were synthesized with different dopant concentration in aqueous phase. Prepared QDs were analytically characterized for their structural, optical and compositional informations. Prepared SDC QDs possessed cubic zinc blende crystalline structure, which was revealed through XRD studies. XRD patterns also elucidate that the crystalline nature was not altered by the dopant ion incorporation. The optical response of SDC QDs revealed the size and dopant dependent optical properties. Presence of different functional groups and it's composition confirmed the formation of SDC QDs and it also confirmed the superior capping effect of thiol capping agent. Formation of SDC QDs was further confirmed by XPS analysis through binding energy variation of individual elements. Sandwich type QDs senstized solar cell was fabricated to study the photovoltaic response of the prepared QDs. At the standard illumination condition, Sb doped CdTe QDs sensitized TiO2 photoanodes showed superior photovoltaic response than pure CdTe QDs.

Effect of Sb doping on microstructure, mechanical and electronic properties of Mg2Si in Mg2Si/AZ91 composites by experimental investigation and first-principles calculation

In this work, the effect of Sb addition on the microstructure and mechanical properties of Mg2Si phase in Mg2Si/AZ91 composites are investigated by experimental research and first-principles calculation. The experimental results show that the coarse dendritic shape is modified to blocky polygonal shape, and the size of primary Mg2Si, is successfully refined with the Sb addition. With enhancing Sb addition contents, the doping concentration of Sb in Mg2Si phase keeps increasing, which accounts for the morphology and size modification. Besides, nano-indentation tests reveal that the Young’s modulus of Mg2Si phase exhibits less reduction, while the hardness is significantly improved when introducing 2.0 wt%Sb. The calculated results indicate that the structure stability of Mg2Si crystal is enhanced, and the mechanical modulus including bulk modulus, shear modulus and Young’s modulus of Mg2Si are decreased with the increase of Sb concentration, agreeing well with experimental observation, but the hardness reduces, which is contrary to the experimental results. Mg2Si phase doping with Sb atoms, however, exhibits improved ductile behavior compared with undoped Mg2Si due to the increased Poisson’s ratio and B/G ratio. In addition, Sb doping can weaken the bond strength and reduce the population of Mg-Si covalent bonds, as well as generate new Mg-Sb bonds with lower strength based on the electronic structure analysis, which contribute to the decrease of mechanical modulus.

Investigation on the optical and electrical properties of undoped and Sb-doped SnO2 nanowires obtained by the VLS method

In this work, we report the effects of Sb doping on the optical and electrical properties of the SnO2 nanowires obtained by the vapor-liquid-solid (VLS) method. The absorption edges were found to be 3.30 eV and 3.66 eV for undoped SnO2 and Sb-doped SnO2 (ATO) nanowires, respectively. The energy shift was related to the Burstein-Moss effect taking place in the doped nanowires. We studied the ATO optical bandgap (ΔE = 0.36 eV) shift as a function of carrier concentration. The incorporation of Sb caused the resistivity to decrease three orders of magnitude for single-nanowire ATO devices. In addition, it was found that undoped SnO2 nanowires exhibit semiconductor characteristics while a metal-insulator transition (MIT), around 170 K, was observed in the ATO nanowires.

Effect of Sb doping on 112 Fe based superconductors: Density functional theory study

The effect of Sb doping at As-chain site of the recently discovered 112 (i.e., CaFeAs2) iron based superconductors is studied with density functional theory based ab-initio electronic structure calculation. Our electronic structure calculation shows that there is an enhancement of As partial density of states in Sb doped 112 compounds. Thus, there exist possibility of enhanced superconductivity in Sb and rare earth co-doped 112 superconductors. Further our first principles calculation also reveals the fact that enhancement in As partial density of states for Sb doping in different rare earth doped 112 compounds is also different.

Sb-doping effects on twin-shift option and microwave dielectric properties of Ba8CoNb6O24 eight-layer hexagonal perovskite ceramics

B-site deficient eight-layer hexagonal perovskites possess in general high quality factors and large positive temperature coefficients of resonant frequency (τf). Recently we successfully lowered τf of shifted perovskite Ba8CoNb6O24 down to near zero through one-third Ta5+ substitution but raised the cost of the materials. In this work, Ba8CoNb6O24 was doped with cheaper elements Sb5+ on Nb5+ sites using conventional solid-state reactions, and near-zero τf of 0.66(2) ppm/°C, modest εr of 27.99(3), Q × f of 1.016(6) × 104 GHz, and significantly reduced cost of the ceramics were achieved on the composition Ba8CoNb5.4Sb0.6O24. The lower polarizability of Sb5+ than Nb5+ results in smaller εr and therefore τf values. About 15 % Sb5+ substitution for Nb5+ in Ba8CoNb6-xSbxO24 dramatically transforms the shifted structure to twinned structure, in contrast with 50 % Ta5+ substitution in the Ta5+ case. This is ascribed to reduced SOJT effects and ionic size of d10 Sb5+ compared with d° Nb5+ and Ta5+.

Effect of Sb doping on the photocatalytic performance of Z-scheme TiO2NRA/SnO2/potassium titanate heterojunction and its photocatalytic mechanism

Firstly, Sb–SnO2/potassium titanate (Sb–SnO2/K4TiO4 (KTO)) was fabricated by a sol-gel method, and then TiO2 nanorod arrays were grown on the surface of Sb–SnO2/KTO by a hydrothermal method (TiO2NRA/Sb–SnO2/KTO). The photocatalytic activity was evaluated by degrading tetracycline hydrochloride (TCH). The prepared samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), ultraviolet–visible diffuse reflectance spectrometer (UV–Vis), and X-ray photoelectron spectroscopic characterizations (XPS). The results show that the Z-scheme heterojunction formed between SnO2/KTO and TiO2 can enhance the range of light response. With the doping of Sb, the conductivity of the composite is enhanced, which is advantageous to the transfer of electron and the low recombination rate of electron-hole pairs. Thus, the doping of Sb is effective to improve the photocatalytic performance. Our work demonstrates the optimal doping amount of Sb is 5%. The degradation efficiency of TCH concentration can reach 95.6% after 2 h and TiO2NRA/Sb–SnO2/KTO shows good reusability.

Improvement of the dust removal performance of a high-transmittance SnO2–SiO2 film by Sb doping

Dust on outdoor glass will significantly reduce glass transmittance in various applications and even damage solar cell panels. Here, the effects of Sb doping on the structure and photoelectric properties of a Sb-doped SnO2–SiO2 (ATO-SiO2) film prepared on a glass substrate with a sol-gel method and the dust removal performance of the resulting film were studied. The results show that the Sb-doped SnO2–SiO2 film consists of a SnO2 tetragonal rutile phase, but the doped Sb decreases the sample crystallinity. With an increase in the Sb doping concentration, two lattice parameters of the ATO-SiO2 film, a and c, show “M"-shaped changes. The nanoparticle size first decreases and subsequently increases when the Sb doping concentration is over 6 mol%. The transmittance of the substrate glass coated with this film in the visible wavelength range (380–780 nm) decreases from 86.3% to 82.7%. The square resistance first decreases and subsequently increases, while the dust removal performance first increases and subsequently decreases. At a 12 mol% Sb doping concentration, the square resistance is minimal (4.64 × 106 Ω/□). The maximal dust removal performance is 64%.

Influence of antimony on the structural, electronic, mechanical, and anisotropic properties of cubic barium stannate

Throughout this study, we have investigated Sb doping’s effects on the physical metallurgy of perovskite BaSnO3 by employing the first-principles calculations based on the density functional theory (DFT). We observed an increasing trend of lattice constants with an increasing doping concentration of Sb on perovskite BaSnO3. The calculated formation enthalpy and elastic constants ensured the structural stability of our system even under varied doping of Sb. Our band structure calculations suggested that it would be possible to tune the band structure of BaSnO3 by partially substituting Sb at the Sn-site, which reduced the band gap at low doping levels and transformed the compound from semiconducting to metallic at Sb ≥ 12.5%. The mechanical properties exhibited the prominent effects of Sb doping. In addition, the anisotropy of our system was significantly dependent on the elastic constant Cij and varied as the doping concentration of Sb is increased. Therefore, our simulation outputs clearly illustrated the importance of taking into account the Sb doping influence on the physical properties of BaSnO3 perovskite material.