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Hydrogen (H 2) holds promise as a replacement for conventional fossil fuels in future energy systems. However, developing a rapid, highly sensitive, and cost-effective H₂ sensor remains a significant challenge. This study first uses a low-cost-oriented Cu x Pd binary alloy for SnO 2 for H 2 sensing, and the corresponding properties are evaluated comprehensively. The results of H 2 sensitivity demonstrate that our bimetallic Cu x Pd significantly enhances the sensitivity of SnO 2 , which is attributed to the synergistic effect of Cu x Pd bimetallic catalysts Our Cu x Pd/SnO 2 nanocomposite materials not only exhibit high response (401 @ 1000 ppm at 100 °C), rapid response/recovery time (1/12 s @ 1000 ppm at 100 °C) and still maintains good response (1.42) to 1 ppm H 2 gas. The introduction of Cu effectively stabilizes Pd and creates more oxygen vacancies, which provides a more catalytic effect than monometallic Pd. Therefore, this work provides a scenario for low-cost catalysis of H 2 detection. • High performance hydrogen sensitive materials prepared by in-situ synthesis. • The resultant Cu 3 Pd/SnO 2 material mainly consists of nanoparticles with sizes around 10–20 nm. • The prepared device has a good response to low concentration hydrogen. • For 1000 ppm hydrogen at 100 °C, the material's response and recovery time is around 1/12s. • The prepared material can effectively increase the proportion of oxygen vacancy. [ABSTRACT FROM AUTHOR]

Ammonia gas detection has garnered widespread attention in various fields, including food, environmental industries, and medical diagnostics. In this article, we present the synthesis of graphene-based tin oxide (graphene–SnO2) hybrid nanostructures using the hydrothermal method. Pristine tin oxide nanostructures and a series of graphene-based tin oxide hybrids containing 5 wt.%, 10 wt. %, 15 wt. %, and 20 wt. % graphene concentrations were fabricated to investigate their response as ammonia gas sensors. The X-ray diffraction and high-resolution transmission electron microscopy analysis revealed the tetragonal rutile crystal structure of both pristine SnO2 and graphene–SnO2 hybrid structures. The morphology of the synthesized structures was examined using scanning electron microscopy. Fourier transform infrared spectroscopy was employed to validate the functional groups present in the hybrid structures, while the band gap of the graphene–SnO2 nanohybrid structures was determined using diffuse reflectance spectroscopy. X-ray photoelectron spectroscopy was utilized to investigate the chemical composition, electronic state, and bonding of the materials. Four probe current–voltage (I–V) measurements were conducted to investigate conductivity and ammonia-sensing behavior. Upon exposure to ammonia gas fumes, the pristine SnO2 exhibited changes in current and resistance, ranging from 0.063 mA to 3.75 mA and 15.87 kΩ to 266.67 Ω, respectively. Similarly, the ammonia sensing behavior of hybrid structures containing 20 wt. % graphene showed changes in current and resistance, ranging from 5.42 mA to 37.8 mA and 0.18 kΩ to 26.45 Ω, respectively. These findings suggest that graphene–SnO2 hybrid structures exhibit excellent conductivity when exposed to NH3 gas, unlike their ammonia-absence counterparts. [ABSTRACT FROM AUTHOR]

A simple two step synthetic method for di‐doped crystalline mesoporous tin dioxide powder containing antimony and fluoride at ambient pressure and temperature has been developed. This approach produced materials with high surface areas and improved electrical and optoelectrical conductance. The two dopant elements; antimony and fluoride were introduced to tin dioxide by two approaches. Both approaches produced mesoporous tin dioxide with antimony and fluoride that are integrated in the framework. The structures of these materials are analyzed by powder X‐ray diffraction, N2 sorption analysis, transmission electron microscopy, energy dispersive X‐ray spectroscopy and X‐ray photoelectron spectroscopy. The conductance of the materials improved by factor of 13–34 compared to undoped mesoporous tin dioxide. The effect of the di‐doped elements on structure, conductance and optoelectronic properties of these materials are discussed in this paper. [ABSTRACT FROM AUTHOR]

Indium‐based transparent conductive oxide (TCO) films are widely used in various photoelectric devices including silicon heterojunction (SHJ) solar cells. However, high cost of indium‐based TCO films is not conducive to mass production of the SHJ solar cells. A variety of indium‐free or indium‐less TCOs are explored and utilized presently. Here, SnOx films are deposited by reactive plasma deposition (RPD) with metal tin as the evaporation source. The metal‐reaction deposited SnOx films feature low resistivity (<2 × 10−3 Ω cm), high mobility (35.93 cm2 V−1 S−1), and wide optical bandgap (3.64 eV). A power conversion efficiency (PCE) of 25.33% is achieved on the champion SHJ solar cell using the metal‐reaction deposited SnOx as the back TCO layer, which indicates the application potential of the metal‐reaction‐deposited SnOx as a low‐cost substitute for In‐based TCOs in SHJ solar cells and other photoelectric devices. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) and tin dioxide (SnO2) form composites in a wide range of SnO2/rGO proportions, which are deposited as thin films on borosilicate glass and silica substrates. The rGO proportion affects the SnO2 optical properties and the sample surface, as observed by optical transmittance and confocal and scanning electron microscopies images, mainly for high proportion of rGO. For low proportion, the presence of small surface islands may contribute to optical confinement. The evaluated bandgap is basically from the SnO2 matrix unless the presence of rGO affects the optical absorption edge. Monochromatic ultraviolet light from a He–Cd laser (325 nm) irradiating on the composite film increases the conductivity, giving rise to the phenomenon of persistent photoconductivity (PPC), even very close to room temperature. Modeling by considering mainly the SnO2/rGO interface barrier for electron transport, yield an interface energy barrier of 250 meV. The strong response to ultraviolet light and the phenomenon of PPC indicates potential application in amplifiers, which could be adjusted by doping with rare‐earth ions, such as Er3+ in the SnO2 matrix. [ABSTRACT FROM AUTHOR]

The presence of various defects within the electron transport layer (ETL), the perovskite (PVK) layer, and their interfaces significantly affects the efficiency, hysteresis, and stability of perovskite solar cells (PSCs) in n–i–p structure. Herein, a defect passivation strategy employing potassium 4‐methoxysalicylate (MSAK) is utilized to efficiently modulate the defects in the ETL, PVK, and ETL/PVK interface. The functional groups −COO− and −OH in MSAK molecules, along with the K+ cations, effectively reduce the defects of tin oxide (SnO2) and improve the electron transport properties. Importantly, the MSAK‐SnO2 provides a favorable substrate for the growth of highly crystallization and dense perovskite layers. The MSAK molecules also significantly passivate the bottom interface defects of the PVK layer by coordinating with under‐coordinated Pb2+ ions. Furthermore, K+ cations can migrate into the PVK layer, further enhancing crystallization and improving the photovoltaic performance of PSC devices. PSCs fabricated using the defect passivation strategy based on MSAK achieve a remarkable power conversion efficiency (PCE) of 25.47%, alongside reduced hysteresis and enhanced stability. After being stored under ambient conditions for 60 days, the device with MSAK maintains nearly 90% of its initial PCE, whereas the PCE of the pristine device decreases to 69.7% after aging. [ABSTRACT FROM AUTHOR]

The volt-ampere characteristics of the sensitive elements of gas sensors are investigated and plotted in coordinates corresponding to various mechanisms of the transfer current. It has been established that the prevailing mechanism of current transfer in the section from 0 to 6 V is Om's law, in the interval (3 - 6) V the Mott's law is fulfilled, and at higher voltages deviations from these laws are observed. It is determined that the laws of Om and Mot confirm the mechanism of the flow of currents limited by the space charge. [ABSTRACT FROM AUTHOR]

This study investigates the fabrication and performance of SnO2 thin films for gas sensing applications, utilizing a deposition method at 2 bar pressure and 8 ml/min flow rate. A multilayer structure was developed, comprising 14 layers, each with a thickness of 250 nm, optimized for sensitivity and stability. The gas sensor, featuring a film heater and sensitive elements doped with a 1% silicon additive, demonstrated a wide operational temperature range (20-370 °C). Characterization of resistance changes revealed significant hysteresis before isothermal annealing, with resistance values stabilizing after prolonged exposure to 370 °C. Post-annealing, the sensor exhibited three orders of magnitude higher resistance, indicating improved stability and electronic transport properties. Doping with a 1N AgNO3 solution significantly enhanced sensitivity to ammonia, with a detection threshold of 500 ppm, while sensitivity to alcohol vapors decreased, indicating selectivity. Experimental results confirm that local doping and thermal treatment effectively enhance the metrological characteristics of SnO2-based sensors, making them suitable for detecting toxic gases. [ABSTRACT FROM AUTHOR]

The interface mismatch between electrochromic materials and conductive layer seriously affects the cycle stability of electrochromic smart windows (ESW). However, it is difficult to improve the interface matching at the same time because of the different physical and chemical properties of anode and cathode materials. In this work, SnO 2 nanosheets are used as the interface modification layer between electrochromic materials and conductive layer. SnO 2 interface engineering significantly can improve the cycle stability of WO 3 film and Prussian blue (PB) film. The WO 3 /SnO 2 -PB/SnO 2 complementary ESW exhibits a high optical modulation of 60.2 % at 633 nm, fast response time (bleached/colored time = 8.5/2.5 s), and coloration efficiency of 91.7 cm2 C−1. The WO 3 /SnO 2 -PB/SnO 2 device can still maintain an optical modulation of 45.2 % after 2000 cycles, suggesting excellent long cycle stability. And the device shows the energy storage of 5.06 mF cm−2 at 0.1 mA cm−2, which can improve energy efficiency. The excellent electrochromic properties and energy storage suggests that SnO 2 interface engineering has a good application prospect in multi-functional ESW with excellent cycle stability. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Xi'an Jiaotong University is the property of Editorial Office of Journal of Xi'an Jiaotong University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tin dioxide (SnO2) is a low-cost and high-capacity anode material for lithium-ion batteries, but the fast capacity fading significantly limits its practical applications. Current research efforts have focused on preparing sophisticated composite structures or optimizing functional binders, both of which increase material manufacturing costs. Herein, we utilize pristine and commercially available SnO2 nanopowders and enhance their cycling performance by simply narrowing the potential range and optimizing electrolytes. Specifically, a narrower potential range (0–1 V) mitigates the capacity fading associated with the conversion reaction, whereas an ether-based electrolyte further suppresses the volume expansion related to the alloy reaction. Consequently, this SnO2 anode delivers a promising battery performance, with a high capacity of ~650 mAhg−1 and stable cycling for 100 cycles. Our work provides an alternative approach to developing high-capacity and long-cycling metal oxide anode materials. [ABSTRACT FROM AUTHOR]

A new approach for the thermal reduction of tin dioxide (SnO2) in the carbon/sodium sulfite (Na2SO3) system is demonstrated. The process of tin smelting was experimentally optimized by adjusting the smelting temperature and amounts of the chemical components used for the thermal reduction of SnO2. The numbers obtained are consistent with the thermodynamic characteristics of the system and molar fractions of reactants derived from the proposed mechanism of the SnO2 thermal reduction process. They reveal that the maximum yield of tin is obtained if masses of C, Na2SO3 and SnO2 are approximately in the ratio 1:2:3 and the temperature is set to 1050 °C. The key role in the suggested mechanism is the thermal decomposition of Na2SO3. It was deduced from the available experimental data that the produced sulfur dioxide undergoes carbothermic reduction to carbonyl sulfide—an intermediate product involved in the bulk reduction of SnO2. Replacing sodium sulfite with sodium sulfate, sodium sulfide and even elemental sulfur practically terminated the production of metallic tin. The kinetic analysis was focused on the determination of the reaction orders for the two crucial reactants involved in the smelting process. [ABSTRACT FROM AUTHOR]

This study investigates the fabrication and performance of SnO2 thin films for gas sensing applications, utilizing a deposition method at 2 bar pressure and 8 ml/min flow rate. A multilayer structure was developed, comprising 14 layers, each with a thickness of 250 nm, optimized for sensitivity and stability. The gas sensor, featuring a film heater and sensitive elements doped with a 1% silicon additive, demonstrated a wide operational temperature range (20-370 °C). Characterization of resistance changes revealed significant hysteresis before isothermal annealing, with resistance values stabilizing after prolonged exposure to 370 °C. Post-annealing, the sensor exhibited three orders of magnitude higher resistance, indicating improved stability and electronic transport properties. Doping with a 1N AgNO3 solution significantly enhanced sensitivity to ammonia, with a detection threshold of 500 ppm, while sensitivity to alcohol vapors decreased, indicating selectivity. Experimental results confirm that local doping and thermal treatment effectively enhance the metrological characteristics of SnO2-based sensors, making them suitable for detecting toxic gases.

The volt-ampere characteristics of the sensitive elements of gas sensors are investigated and plotted in coordinates corresponding to various mechanisms of the transfer current. It has been established that the prevailing mechanism of current transfer in the section from 0 to 6 V is Om’s law, in the interval (3 - 6) V the Mott’s law is fulfilled, and at higher voltages deviations from these laws are observed. It is determined that the laws of Om and Mot confirm the mechanism of the flow of currents limited by the space charge.

It has been shown that Sn implantation with subsequent annealing in air leads to an increase in the electroluminescence (EL) intensity of SiO2/Si structure by two orders of magnitude. Intense violet EL with a maximum at 3.21 eV was observed at room temperature by the naked eye at forward bias. The observed emission was attributed to radiative recombination in SnO2 nanocrystals synthesized in SiO2 layers. The external quantum efficiency (EQE) increased with decreasing Sn concentration The maximum external quantum efficiency was found to be 0.7 % for the silica film Sn-implanted at the lowest fluence of 2.5 × 1016 cm−2. The non-radiative charge transport (shunt current) through the sample and mechanism of EL excitation are discussed. It has been concluded that the Poole–Frenkel mechanism, or tunneling between traps are the most likely mechanisms of charge transport to light-emitting centers.

Tin dioxide (SnO2) is an oxide semiconductor with n-type characteristics, with high transparency in the UV–Vis, where the donors are usually associated with oxygen vacancies and interstitial tin ions. Quinoline derivatives (QD) are usually p-type semiconductors with emission in the blue range. We report photo-induced properties of the QD 4-(6-(diethylamino)-4-phenylquinolin-2-yl)benzoic acid and the combination with the inorganic semiconductor oxide SnO2, both layers in the form of thin film, which forms a heterostructure. Thin film is a very convenient format for integration in optoelectronics. Emission of the QD takes place in blue range (470–485 nm) and depends on the solvent when in solution, being used acetone and tetrahydrofuran (THF). However, when in the form of thin film, it does not depend on the solvent. Concerning the heterostructure, it is explored under distinct device architecture: 1) combination in a transport profile perpendicular to the films (transverse contacts) leading to a rectifying behavior similar to a p-n junction, which is evidence of the p-type-like electrical behavior of the QD; 2) in parallel conduction profile, where there seems to exist some sort of interfacial phenomenon similar to a two-dimensional electron gas (2-DEG), a property that can be explored in transparent high-mobility transistors.

Metal oxides are versatile catalysts in organic synthesis, exhibiting diverse properties such as acidity, basicity, redox behaviour, and stability. Among these, tin dioxide (SnO₂) stands out for its resilience and durability, making it a preferred catalyst. The reduced ionic character and high oxidation state (+4) of tin dioxide contribute to its heightened acidity. Tin dioxide based materials have gained significant attention as catalysts in heterocycle synthesis, cross-coupling, decarboxylation, ring-opening and ring-closing reactions, biodiesel synthesis, and glycerol transformations. Additionally, SnO₂-based materials are also employed as photocatalysts and photo-electrocatalysts.

This study investigates conductive, transparent films of undoped and Ni-doped SnO 2 deposited through water solvent spray pyrolysis, aiming to combat environmental water pollution. Examining these films using X-ray diffraction (XRD), Fourier transform infrared absorption microscopy (FTIR), UV–Vis spectrophotometer, and Hall effect, the research focuses on photocatalytic degradation kinetics using rhodamine B (RhB) as a model pollutant from the textile industry. XRD results confirm tetragonal structures of SnO 2 and Ni: SnO 2 films with crystallite sizes ranging from 21.83 to 19.52 nm. The sprayed films exhibit resistivity variations (7.1 × 10−3 to 4.5 × 10−3) Ω.cm and figure of merit variations [(1.49 × 10−4 to 25.03 × 10−4); (2.69 × 10−4 to 9.1 × 10−4)] (Ω/sq)−1. Optical properties include ∼73% light transmission, ∼20% reflection, and ∼7% absorptance, with porosity (8.65–11.44)%, refractive index (2.88–1.57), extinction coefficient (0.0043–0.0013), dielectric constants (8.31–2.48 and 0.025–0.0041), optical density [(3.9 × 10+10–7.86 × 10+09) S−1], skin depth [(2.06 × 10−3–6.7 × 10−3) cm−1], and optical band gap with Urbach energy [(3.8–3.6) eV and (0.67–0.43) eV] obtained at 550 nm. The photocatalytic process, crucial for water pollution treatment, exhibits pH sensitivity (12.3–1.7) over varied times (0–90 min) and is influenced by the SnO 2 thin film elaboration method. Notably, 0.5 M-concentration SnO 2 films show the most efficient photocatalytic degradation rates. This research highlights the potential of SnO 2 in environmentally friendly water pollution treatment, emphasizing its practical application in addressing crucial environmental challenges. [ABSTRACT FROM AUTHOR]

Nanosized initial semiconductor tin dioxide based material was synthesized by a sol-gel technique and characterized by XRD, IR-spectroscopy, DTA-DTG and TEM methods. Nanosized SnO2-based sensor materials were prepared using the pastes with different quantities of tin dioxide and carboxymethyl cellulose and formatted at various temperatures. It was found that the compositions of the pastes significantly affect the characteristics of the sensors obtained on their base. The characteristics of the sensors of different compositions were explained by necessity of the presence of sufficient number of contacts between the nanoparticles of the sensor material, which ensure the electrical conductivities of the sensors. [ABSTRACT FROM AUTHOR]

In this work, we have studied the microstructure and unusual ferromagnetic behavior in epitaxial tin dioxide (SnO2) films implanted with 40 keV Co+ ions to a high fluence of 1.0 × 1017 ions/cm2 at room or elevated substrate temperatures. The aim was to comprehensively understand the interplay between cobalt implant distribution, crystal defects (such as oxygen vacancies), and magnetic properties of Co-implanted SnO2 films, which have potential applications in spintronics. We have utilized scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometry (VSM), differential thermomagnetic analysis (DTMA), and ferromagnetic resonance (FMR) to investigate Co-implanted epitaxial SnO2 films. The comprehensive experimental investigation shows that the Co ion implantation with high cobalt concentration induces significant changes in the microstructure of SnO2 films, leading to the appearance of ferromagnetism with the Curie temperature significantly above the room temperature. We also established a strong influence of implantation temperature and subsequent high-temperature annealing in air or under vacuum on the magnetic properties of Co-implanted SnO2 films. In addition, we report a strong chemical effect of ethanol on the FMR spectra. The obtained results are discussed within the model of two magnetic layers, with different concentrations and valence states of the implanted cobalt, and with a high content of oxygen vacancies. [ABSTRACT FROM AUTHOR]

Halogen-doped tin dioxide (SnO2) is examined for its photocatalytic activity and further applications apart from the photovoltaic devices. While SnO2 has been extensively examined in energy devices, not so much attention has been paid to its investigation as a photocatalyst. Preliminary studies on photocatalytic properties suggest that Br:SnO2 shows a small improvement in hydrogen production in the first 14 h, whereas, in general, the presence of any halogen reduces the reactivity of SnO2. By incorporating this result with the observed increase in conductance, it can be suggested that the doping of Cl and Br serves as an effective method for enhancing the electron-transport properties of SnO2 layers. [ABSTRACT FROM AUTHOR]

This work aims to study the effect of Mn 2 O 3 additions on the electrical properties and microstructure characteristics of a SnO 2 -based ceramic varistor system doped additionally with Sb 2 O 5 , Cr 2 O 3 , and CoO. The specimens were prepared using conventional ceramic processing and homogenized by a high-energy ball milling system using the following composition: (98.99-X) % SnO 2 – 0.05% Cr 2 O 3 – 0.05% Sb 2 O 5 – 1.00% CoO – X% Mn 2 O 3 where X = 0.00, 0.05, 0.10, 0.20, 0.50 and 1% mol. Characterization by TG-DSC/DTA, XRD, XPS, and SEM/EDS, and the proposed chemical and defect-formation reactions allowed the conclusion that Mn 2 O 3 additions produce alterations of the microstructure consisting of the in situ formation of the spinel Co 2 MnO 4 secondary phase and modification of the potential barriers in the intergranular regions, where, in addition, oxygen vacancies are formed. With the 0.05 mol % Mn 2 O 3 , the grain size (average in the range of 2–3 μm) drops by 20 %, thus augmenting the grain boundaries. Altogether, this leads to a decrease in the nonlinearity coefficient (α) and an advantageous displacement of the breakdown electric field (E B). The 0.05 mol % Mn 2 O 3 specimen compares favorably with the reference material by surpassing the E B value by a factor of 8. Elucidation of Mn2+ and Co2+ in 1 mol % Mn 2 O 3 specimens by XPS suggests the role of MnO and CoO as intermediate phases, essential for Co 2 MnO 4 formation. The pathway for in situ formation of Co 2 MnO 4 is set forth based on the above characterization techniques in conjunction with proposed chemical and defect-formation reactions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This academic article investigates the performance of dye-sensitized solar cells (DSSCs), which are affected by various defects like charge recombination, high impedance, and low power conversion efficiency due to complex physicochemical phenomena. The study explores different materials and processes to enhance DSSC performance, with a focus on photoanode development. Tin dioxide, tin chloride II dihydrate, copper oxide, boric acid, and sodium phosphate are utilized to fabricate the photoanodes. A thermal treatment at 450°C for 30 minutes precedes dye assembly on the photoanode surface. Results show that the tin chloride II dihydrate-modified photoanode outperforms others, achieving higher open-circuit voltage (0.50V), current density (9.58 mAcm-2), fill factor (0.37), and power conversion efficiency (1.77%). The study suggests that tin salt particles positively impact voltage, current, electron transport, and charge separation, enhancing overall cell performance. Charge recombination significantly affects power conversion efficiency and impedance, but accurately quantifying it remains challenging. Lower recombination levels favor efficiency, while higher levels reduce it.

This paper reviews selected problems, which appear in literature dealing with TiO2, SnO2, and ZnO. Some of them have more universal impact to semiconductor electrochemistry. The electronic band structure is a key for understanding fundamental properties and for rational design of applications, but the uncertainty of specific values determined experimentally or by theoretical calculations should not be ignored. The inappropriate use of Mott-Schottky plot for characterization of certain semiconductor electrodes is another source of problems. Some other technical and formal issues in research and development of semiconductors are discussed. [ABSTRACT FROM AUTHOR]

The rationally designed reaction between the GO sheets, Sn2+ ions and GA molecules in mild hydrothermal condition contributes to the formation of an intermediate SnO 2 @GA@RGO sample with a MOF on graphene configuration, which is converted to the final SnO 2 /C/RGO composite with optimized microstructures after thermal treatment. [Display omitted] Tin dioxide (SnO 2) is being investigated as a promising anode material for both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Effectively dispersing small sized SnO 2 crystals in well-designed carbonaceous matrices using eco-friendly materials and simplified methods is an urgent task. Herein, gallic acid (GA) molecules, abundant in plant kingdom, are firstly selected to react with few-layered graphene oxide (GO) in mild hydrothermal condition, and the GA modulated reduced graphene oxide (GA@RGO) supporting skeleton can be obtained. Then Sn-GA metal–organic framework (MOF) domains can be directly engineered on the surface of the GA@RGO sheets with controlled size and improved dispersion. Finally, the well-designed Sn-GA@RGO precursor is converted to the SnO 2 /C/RGO nanocomposite with significantly optimized microstructure. The SnO 2 /C/RGO sample delivers an excellent specific capacity of 823.6 mAh·g−1 after 700 cycles at 1000 mA·g−1 in half-cells and 741.3 mAh·g−1 after 50 cycles at 200 mA·g−1 in full-cells for LIBs, a specific capacity of 370.3 mAh·g−1 after 600 cycles at 200 mA·g−1 in half-cells for SIBs. The sample preparation strategy is rationally established by comprehensively understanding the interactions between GO sheets, Sn2+ ions and GA molecules, and the engineered SnO 2 /C/RGO nanocomposite has good prospects in wider fields. [ABSTRACT FROM AUTHOR]

Most of the studies on tin oxide coatings as electrode materials were conducted on titanium; in this study, the aim was to create pure tin oxide (SnO2) films on graphite substrate, which is more prevalent than titanium. There is a lack in investigation the effect of SnCl2 and HNO3 concentrations on the prepared SnO2 electrode; therefore, the aim of this work was to study these effects precisely. Also, no previous study investigated the removal of phenol sonoelectrochemically by a SnO2 electrode, which would be accomplished in the present work. The tin dioxide electrode was produced by cathodic electrodeposition using a SnCl2·2H2O solution in the presence of HNO3 and NaNO3 on a graphite plate substrate. The impact of various operating parameters (current density - CD, HNO3 concentration, and SnCl2·2H2O concentration) on the morphology and structure of the SnO2 deposit layer was thoroughly investigated. The physical structures of the SnO2 film were determined by X-ray diffraction (XRD), surface morphology was characterized using field-emission scanning electron microscopy (SEM), and chemical composition was analyzed using energy-dispersive X-ray spectroscopy (EDX). In a batch reactor, the sonoelectrochemical oxidation of phenol was tested to determine the performance of the best SnO2 electrodes for phenol degradation and any organic byproducts. It was discovered that 10 mA/cm2, 50 mM of SnCL2·2H2O, and 250 mM of HNO3 were the optimum conditions to prepare SnO2 electrodes, which produced the smallest crystal size, with no appeared cracks, and gave the best phenol removal. The best prepared electrode was tested in the sonoelectrochemical oxidation of phenol with two different electrolytes and different CD, and the results showed that the phenol removal was 76.87% and 64.68% when using NaCl and Na2SO4, respectively, as well as was 63.39, 76.87, and 100% for CD at 10, 25, and 40 mA/cm2, respectively. [ABSTRACT FROM AUTHOR]

Temperature conductivity studies of films based on Cu:SnO2 made by magnetron sputtering of the mixed target CuO/SnO2 have been carried out. Temperature conductivity dependencies were substantially nonlinear. It was found that the local conductivity minimum was observed near the temperature of 330°C. To explain the results, a mathematical model is proposed of oxygen adsorption in various forms on the surface of wide-bandgap semiconductors. It was assumed that oxygen particle adsorption resulted in energy levels of the acceptor type localized near the surface of the semiconductor. The simulation carried out within the proposed model showed qualitative and quantitative consistency of the calculation results and experimental data of the temperature dependence of conductivity of the formed gas-sensitive Cu:SnO2 layers in oxygen-containing atmosphere. An analysis of experimental temperature dependence showed that the local conductivity minimum is due to the process of dissociation of oxygen particles adsorbed in molecular form. The desorption energies of each form of adsorbed oxygen and the depth of their surface acceptor level are assessed.

The results of the response study of gas sensors based on gas-sensitive layers Cu:SnO2 to ethanol, acetone, and 2-propanol vapors are presented. Sensor response concentration dependencies are measured at different temperatures to determine optimal operating modes. Experimental temperature dependence of the sensors response to the vapors of the analyzed substances are determined. The dependence is theoretically substantiated by a proposed mathematical model based on consideration of the processes of transfer of charge carriers through the potential barrier grains of a polycrystalline semiconductor film in an oxygen-containing medium and the reducing gas to be analyzed. It is assumed that each type of gas on the surface of SnO2 has its own adsorption centers. The work shows that the model can be used to calculate and predict the gas sensitivity measurements of sensors based on the active layers of polycrystalline semiconductors. The results of the calculations confirm that such energy parameters as the depth of the energy level and the desorption energies are individual for each substance.

The temperature dependencies of the response of Cu:SnO2 films to ethanol, 2-propanol vapours, as well as ethanol with 3% vol. background impurities of 2-prophanol in the working temperature range of 250-375°C. The aim of the study was to determine the effect of the 2-propanol background impurities on the sensor response to ethanol, as well as to assess the possibility of distinguishing a steam-air mixture containing pure ethanol vapors from a gas mixture of ethanol/2-propanole by means of single-sensor signal statistical processing. The temperature dependencies analysis of the sensor response showed that the temperature at which the maximum response is observed is individual for each substance. A selective response to substances was detected. It was found that the 3% vol. isopropyl alcohol compound decreases the response to ethanol in the tested concentration and temperature range. Statistical processing of experimental data by the principal component analysis (PCA) and cross-validation of the model by the ellipsoid and nearest-neighbor showed the fundamental ability to recognize ethanol, 2-propanol and their mixture.

Tin dioxide (SnO2) is a low-cost and high-capacity anode material for lithium-ion batteries, but the fast capacity fading significantly limits its practical applications. Current research efforts have focused on preparing sophisticated composite structures or optimizing functional binders, both of which increase material manufacturing costs. Herein, we utilize pristine and commercially available SnO2 nanopowders and enhance their cycling performance by simply narrowing the potential range and optimizing electrolytes. Specifically, a narrower potential range (0–1 V) mitigates the capacity fading associated with the conversion reaction, whereas an ether-based electrolyte further suppresses the volume expansion related to the alloy reaction. Consequently, this SnO2 anode delivers a promising battery performance, with a high capacity of ~650 mAhg−1 and stable cycling for 100 cycles. Our work provides an alternative approach to developing high-capacity and long-cycling metal oxide anode materials.

This study investigates the effects of annealing time on the optical and electrical properties of tin dioxide coatings, specifically surface resistivity and specific conductivity. The thickness of the film, as well as its density and void density, were calculated from the interference peaks. The results suggest that as the duration of annealing increases, the density of the film decreases and the void volume increases. The lack of interference peaks in the transmission spectra of films containing additives is caused by the development of dendritic structures within the films. As the annealing duration is extended to 6 h, the surface resistivity increases, resulting in a decrease in the specific conductivity of all films. As the duration of annealing increases, the surface resistivity of the films studied increases and therefore their overall quality decreases.

Recently, the production of new photocatalytic materials has attracted considerable attention as a promising strategy to mitigate anthropogenic environmental degradation. In this study, cement paste composites (water/cement ratio = 0.5) were prepared using a coating based on nanoparticles of SnO2 (SnO2/cement paste) and SnO2 decorated with Ag2O (Ag2O-decorated SnO2/cement paste) for photocatalytic applications. These coatings were prepared in this study by using the hydrothermal method as the strategy. Thus, photocatalyst efficiency was evaluated through the degradation of methylene blue (MB) and methyl red (MR) as cationic and anionic dyes, respectively, and the simultaneous degradation of MB/MR (1:1 v/v) dyes. Moreover, the photocatalytic mechanism was investigated in the presence of scavengers. Notably, an increase in pH in the range of 2–6 resulted in selective degradation of the MB/MR dye mixtures. Overall, the photocatalytic performance of these materials provides a novel platform technology focused on advanced civil engineering applications, which consequently facilitates the mitigation of various environmental problems. [ABSTRACT FROM AUTHOR]

The chelation reaction between LS-Na and SnCl 2 under mild hydrothermal condition generates the SnCl 2 @LS sample with a uniform distribution of Sn2+ in the LS domains, which can be further dispersed by GO sheets via a redox coprecipitation reaction. After thermal treatment, the SnCl 2 @LS@GO sample can be converted to the SnO 2 /LSC/RGO composite with improved micro-structure. [Display omitted] Tin dioxide (SnO 2) is widely recognized as a high-performance anode material for lithium-ion batteries. To simultaneously achieve satisfactory electrochemical performances and lower manufacturing costs, engineering nano-sized SnO 2 and further immobilizing SnO 2 with supportive carbon frameworks via eco-friendly and cost-effective approaches are challenging tasks. In this work, biomass sodium lignosulfonate (LS-Na), stannous chloride (SnCl 2) and a small amount of few-layered graphene oxide (GO) are employed as raw materials to engineer a hierarchical carbon framework supported SnO 2 nanocomposite. The spontaneous chelation reaction between LS-Na and SnCl 2 under mild hydrothermal condition generates the corresponding SnCl 2 @LS sample with a uniform distribution of Sn2+ in the LS domains, and the SnCl 2 @LS sample is further dispersed by GO sheets via a redox coprecipitation reaction. After a thermal treatment, the SnCl 2 @LS@GO sample is converted to the final SnO 2 /LSC/RGO sample with an improved microstructure. The SnO 2 /LSC/RGO nanocomposite exhibits excellent lithium-ion storage performances with a high specific capacity of 938.3 mAh/g after 600 cycles at 1000 mA g−1 in half-cells and 517.1 mAh/g after 50 cycles at 200 mA g−1 in full-cells. This work provides a potential strategy of engineering biomass derived high-performance electrode materials for rechargeable batteries. [ABSTRACT FROM AUTHOR]

In this study, undoped tin dioxide (SnO2) thin film and tin dioxide doped with various concentrations of silver oxide (AgO) thin films have been deposited on glass substrates using chemical spray pyrolysis. The developed films were analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and UV–visible spectrophotometer to investigate the structural, morphological and optical characteristics. The X-ray analysis showed a polycrystalline nature, and the crystallite size increased from 50.3 to 72.4 nm as the AgO concentration increased. AFM and SEM results showed that the average grain size of SnO2 films increased with the AgO-dopant contents. The topographical analysis of the prepared films showed that the average surface roughness increased from 2.26 to 3.13 nm with an increase in the AgO-dopant material. Optically, the increase in the AgO-dopant content had an optical effect on the tin dioxide films, as the optical transmittance reduced and the refractive index increased. Increase in dopant content reduced the energy gap from 3.75 to 3.6 eV. [ABSTRACT FROM AUTHOR]

SnO2 – x nanocrystal films with Gd, Tb, Yb, Lu, and Sb additives for resistive gas sensors are fabricated by the magnetron sputtering of a composite target in a mixture Ar and O2 on quartz substrates with subsequent heating in air up to 350–400°C with resistance control. Sb as a donor is introduced into the composition of all the sensors and provides the given resistance values. The resistance of the sensors upon heating in air has a minimum in the range of 180–220°C and increases with temperature as a result of the field effect associated with oxygen adsorption on the film surface and the capture of film electrons. The composition of the films and their surface properties are investigated by electron microscopy and atomic-force microscopy. The resistance of the sensors is determined by the fabrication regime and may be equal from tens of kOhm up to ten of MOhm. The optimal working temperature is in the range of 280–350°C under a heating power of 500 mW. The sensors have a high sensitivity to alcohols which increases with the molecular mass of the reagent and all the sensors have a low sensitivity to benzene and acetone. The sensors have a short time of reaction to the reagents and a long time of recovery after removal of the reagents from air. The sensors are used to monitor some reagents in air and in devices of the electronic-nose type. [ABSTRACT FROM AUTHOR]

The oxides of group 14 have been widely used in numerous applications in glass, ceramics, optics, pharmaceuticals, and food industries and semiconductors, photovoltaics, thermoelectrics, sensors, and energy storage, namely, batteries. Herein, we simulate and experimentally determine by scanning kelvin probe (SKP) the work functions of three oxides, SiO2, SiO, and SnO2, which were found to be very similar. Electrical properties such as electronic band structure, electron localization function, and carrier mobility were also simulated for the three crystalline oxides, amorphous SiO, and surfaces. The most exciting results were obtained for SiO and seem to show Poole–Frankel emissions or trap-assisted tunneling and propagation of surface plasmon polariton (SPP) with nucleation of solitons on the surface of the Aluminum. These phenomena and proposed models may also describe other oxide-metal heterojunctions and plasmonic and metamaterials devices. The SiO2 was demonstrated to be a stable insulator interacting less with the metals composing the cell than SnO2 and much less than SiO, configuring a typical Cu/SiO2/Al cell potential well. Its surface charge carrier mobility is small, as expected for an insulator. The highest charge carrier mobility at the lowest conduction band energy is the SnO2's and the most symmetrical the SiO's with a similar number of electron holes at the conduction and valence bands, respectively. The SnO2 shows it may perform as an n-type semiconductor. [ABSTRACT FROM AUTHOR]

Tin dioxide has huge potential and is widely studied and used in different fields, including as a sensitive material in semiconductor gas sensors. The specificity of the chemical activity of tin dioxide in its interaction with the gas phase is achieved via the immobilization of various modifiers on the SnO2 surface. The type of additive, its concentration, and the distribution between the surface and the volume of SnO2 crystallites have a significant effect on semiconductor gas sensor characteristics, namely sensitivity and selectivity. This review discusses the recent approaches to analyzing the composition of SnO2-based nanocomposites (the gross quantitative elemental composition, phase composition, surface composition, electronic state of additives, and mutual distribution of the components) and systematizes experimental data obtained using a set of analytical methods for studying the concentration of additives on the surface and in the volume of SnO2 nanocrystals. The benefits and drawbacks of new approaches to the high-accuracy analysis of SnO2-based nanocomposites by ICP MS and TXRF methods are discussed. [ABSTRACT FROM AUTHOR]

This study investigates the effects of annealing time on the optical and electrical properties of tin dioxide coatings, specifically surface resistivity and specific conductivity. The thickness of the film, as well as its density and void density, were calculated from the interference peaks. The results suggest that as the duration of annealing increases, the density of the film decreases and the void volume increases. The lack of interference peaks in the transmission spectra of films containing additives is caused by the development of dendritic structures within the films. As the annealing duration is extended to 6 h, the surface resistivity increases, resulting in a decrease in the specific conductivity of all films. As the duration of annealing increases, the surface resistivity of the films studied increases and therefore their overall quality decreases. [ABSTRACT FROM AUTHOR]

A new approach for the thermal reduction of tin dioxide (SnO2) in the carbon/sodium sulfite (Na2SO3) system is demonstrated. The process of tin smelting was experimentally optimized by adjusting the smelting temperature and amounts of the chemical components used for the thermal reduction of SnO2. The numbers obtained are consistent with the thermodynamic characteristics of the system and molar fractions of reactants derived from the proposed mechanism of the SnO2 thermal reduction process. They reveal that the maximum yield of tin is obtained if masses of C, Na2SO3 and SnO2 are approximately in the ratio 1:2:3 and the temperature is set to 1050 °C. The key role in the suggested mechanism is the thermal decomposition of Na2SO3. It was deduced from the available experimental data that the produced sulfur dioxide undergoes carbothermic reduction to carbonyl sulfide—an intermediate product involved in the bulk reduction of SnO2. Replacing sodium sulfite with sodium sulfate, sodium sulfide and even elemental sulfur practically terminated the production of metallic tin. The kinetic analysis was focused on the determination of the reaction orders for the two crucial reactants involved in the smelting process.

In this work, we have studied the microstructure and unusual ferromagnetic behavior in epitaxial tin dioxide (SnO2) films implanted with 40 keV Co+ ions to a high fluence of 1.0 × 1017 ions/cm2 at room or elevated substrate temperatures. The aim was to comprehensively understand the interplay between cobalt implant distribution, crystal defects (such as oxygen vacancies), and magnetic properties of Co-implanted SnO2 films, which have potential applications in spintronics. We have utilized scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometry (VSM), differential thermomagnetic analysis (DTMA), and ferromagnetic resonance (FMR) to investigate Co-implanted epitaxial SnO2 films. The comprehensive experimental investigation shows that the Co ion implantation with high cobalt concentration induces significant changes in the microstructure of SnO2 films, leading to the appearance of ferromagnetism with the Curie temperature significantly above the room temperature. We also established a strong influence of implantation temperature and subsequent high-temperature annealing in air or under vacuum on the magnetic properties of Co-implanted SnO2 films. In addition, we report a strong chemical effect of ethanol on the FMR spectra. The obtained results are discussed within the model of two magnetic layers, with different concentrations and valence states of the implanted cobalt, and with a high content of oxygen vacancies.

The aim of this study was to design a chitosan-coated hollow tin dioxide nanosphere (CS-HSn) for loading febuxostat (FEB) using an adsorption method to obtain a sustained-release system (CS-HSn-FEB) to improve the oral bioavailability of FEB. The morphological characteristics of hollow tin dioxide nanospheres (HSn) and CS-HSn were analyzed by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The hemolysis test and CCK-8 test were used to assess the biosafety of HSn and CS-HSn. Powder X-ray diffraction (PXRD) and differential scanning thermal analysis (DSC) were performed on CS-HSn-FEB to analyze the drug presence status. The dissolution behavior and changes in plasma drug concentration of CS-HSn-FEB were evaluated in vitro and in vivo. Sections of intestinal tissues from SD rats were obtained to observe whether chitosan could increase the distribution of nanoparticles in the intestinal tissues. The results showed that FEB was present in CS-HSn in an amorphous state. Moreover, CS-HSn, with good biosafety, significantly improved the water solubility and oral absorption of FEB, indicating that CS-HSn has great potential to improve the intestinal absorption and oral bioavailability of insoluble drugs.

The pure semiconductor SnO2 hollow nanosphere (HNS) was synthesized by a carbon sphere (CS) template-assisted in solution phase growth method using Tin (IV) chloride (SnCl4). This HNS is fabricated or formed by aggregations among the adjacent SnO2 nanoparticles at above 100 °C temperature. The difference between the valance and conduction bands gap is found to be 3.387 eV. The whole diameter of the SnO2 HNS is ranged from 300–500 nm in size with the thickness of the wall 40–50 nm. The SnO2 nanoparticle size ranges from 20 to 30 nm. The dimension of the HNS are controlled by adjusting the some parameters, such as the concentration of SnCl4, the aging time, temperature, and the size of carbon spheres. The whole HNS size and wall thickness are affected by the Sn4+, due to the electrostatic force between CS and metal ions. The fabricated semiconductor SnO2 HNS was characterized by various analytical methods such as diffusion reflectance spectrum, Fourier transform infrared spectra, an X-ray diffraction pattern, Energy-dispersive X-ray pattern, Field emission scanning electron microscope (FESEM), and High-resolution transmittance electron microscope. Then, this semiconductor SnO2 hollow nanosphere-modified glassy carbon electrode exhibited excellent electrocatalytic activity for the reduction of hydrogen peroxide (H2O2) and ethanol with corresponding electro potential appeared at − 0.630 and − 0.624 V respectively. The oxidation of bioactive molecules such as Ascorbic acid, Dopamine, and Propyl gallate, with oxidation potential appeared at 0.634, 0.698, and 0.526 V respectively in low reduction potential. [ABSTRACT FROM AUTHOR]

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Cellulose nanofiber (CNF), a natural polymer material with a high specific surface area, is a potential candidate for gas sensors. Here, we report Au/SnO2 composites with excellent performance synthesized by a chemical precipitation method based on CNF-assisted synthesis, and a series of Au/SnO2 composites were prepared by adjusting the Au content. The sensitivity of the 1.5 wt.% Au/SnO2 sensor to a low concentration of 1 ppm NO2 was 53, nearly 17 times higher than that of pure SnO2 synthesized by CNF, under ultraviolet (UV) irradiation at a wavelength of 365 nm. The crystal structure of the composite was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), revealing that the composites had high crystallinity and particles reaching the nanoscale. Further experimental data showed that the CNF-assisted synthesis Au/SnO2 sensors had good selectivity, repeatability, and stability. Additionally, the sensor is able to maintain its excellent gas sensing performance even under varying humidity conditions. [ABSTRACT FROM AUTHOR]

The cycling stability of SnO2 anode as lithium-ion battery is poor due to volume expansion. Polyimide coatings can effectively confine the expansion of SnO2. However, linear polyimides are easily dissolved in ester electrolytes and their carbonyls is not fully utilized during charging/discharging process. Herein, the SnO2 enclosed with anthraquinone-based polyimide/reduced graphene oxide composite was prepared by self-assembly. Carbonyls from the anthraquinone unit provide fully available active sites to react with Li+, improving the utilization of carbonyl in the polyimide. More exposed carbonyl active sites promote the conversion of Sn to SnO2 with electrode gradual activation, leading to an increase in reversible capacity during the charge/discharge cycle. In addition, the introduction of reduced graphene oxide cannot only improve the stability of polyimide in the electrolyte, but also build fast ion and electron transport channels for composite electrodes. Due to the multiple effects of anthraquinone-based polyimide and the synergistic effect of reducing graphene oxide, the composite anode exhibits a maximum reversible capacity of 1266 mAh·g−1 at 0.25 A·g−1, and maintains an excellent specific capacity of 983 mAh·g−1 after 200 cycles. This work provides a new strategy for the synergistic modification of SnO2. [ABSTRACT FROM AUTHOR]