SnO2 Particles Research Articles

Binder-free tin (IV) oxide coated vertically aligned carbon nanotubes as anode for lithium-ion batteries

Despite the tremendous potential of tin oxide (SnO2) as an anode material, irreversible capacity loss due to the sluggish kinetics and structural pulverization as a result of the substantial volume alteration during redox reactions limits its use in lithium-ion batteries. The typical layered design of an electrode consisting of binder and conductive additive can lower the practical capacity of high-capacity electrode materials. We synthesized a binder and conductive additive-free, self-standing core-shell vertically-aligned carbon nanotubes (VACNTs)-SnO2 anode (SnO2-VACNTs) on 3D nickel foam using plasma-enhanced chemical vapor deposition and wet chemical method. The SnO2-VACNTs exhibited excellent cyclability with a specific capacity of 1512 mAh g−1 at 0.1 A g−1 after 100 cycles and 800 mAh g−1 at 1 A g−1 after 200 cycles. The ultra-fine SnO2 particles (<5 nm) shortened the Li+ diffusion paths into the bulk electrode and alleviated the volume alteration by lowering the strains during the redox reactions. Also, proper inter-tube distance between individual SnO2-VACNTs buffered the volume instability and offered better electrolyte accessibility. Direct connection of VACNTs with the current collector ensured an uninterrupted electron conducting path between the current collector and active material, thus offering more efficient charge transportation kinetics at the electrode/electrolyte interfaces.

Facile Synthesis, Sintering, and Optical Properties of Single-Nanometer-Scale SnO2 Particles with a Pyrrolidone Derivative for Photovoltaic Applications

We investigate the preparation of mesoscopic SnO2 nanoparticulate films using a Sn(IV) hydrate salt combined with a liquid pyrrolidone derivative to form a homogeneous precursor mixture for functional SnO2 nanomaterials. We demonstrate that N-methyl-2-pyrrolidone (NMP) plays a crucial role in forming uniform SnO2 films by both stabilizing the hydrolysis products of Sn(IV) sources and acting as a base liquid during nanoparticle growth. The hydrolysis of Sn(IV) was controlled by adjusting the reaction temperature to as low as 110 °C for 48 h. High-resolution TEM analysis revealed that highly crystalline SnO2 nanoparticles, approximately 3–5 nm in size, were formed. The SnO2 nanoparticles were deposited onto F-doped SnO2 glass and converted into dense particle films through heat treatments at 400 °C and 500 °C. This pyrrolidone-based nanoparticle synthesis enabled the production of not only crystallized SnO2 but also transparent and uniform films, most importantly by controlling the slow hydrolysis of Sn(IV) and polycondensation only with those two chemicals. These findings offer valuable insights for developing stable and uniform electron transport layers of SnO2 in mesoscopic solar cells, such as perovskite solar cells.

Stepwise emergence of CO gas sensing response and selectivity on SnO2 using C supports and PtOx decoration.

Room temperature gas sensing is crucial for practical devices used in indoor environments. Among various materials, metal oxides are commonly used for gas sensing, but their strong insulating properties limit their effectiveness at room temperature. To address this issue, many studies have explored diverse methods such as nanoparticle decoration or conductive support, etc. Here, we report the emergence of gas-sensing functionality at room temperature with improved CO gas selectivity on SnO2 nanoparticles through sequential steps by using amorphous carbon (a-C) support and PtOx decoration. The SnO2 decorated on amorphous carbon shows enhanced gas adsorption compared to inactive gas sensing on SnO2 decorated carbon support. The higher Vo site of SnO2 on a-C induces gas adsorption sites, which are related to the higher sp2 bonding caused by the large density of C defects. The ambiguous gas selectivity of SnO2/a-C is tailored by PtOx decoration, which exhibits six values of sensing responses (Rg/Ra or Ra/Rg) under CO gas at room temperature with higher selectivity. Compared to PtOx/a-C, which shows no response, the enhanced CO gas sensing functionality is attributed to the CO adsorption site on PtOx-decorated SnO2 particles. This report not only demonstrates the applicability of CO gas sensing at room temperature but also suggests a strategy for using SnO2 and carbon compositions in gas sensing devices.

Low-temperature/room-temperature gas sensing application for NO2 gas by SnO2 and Ni doped SnO2 nanostructures synthesized by sol-gel method

Gas sensors are the attentive parts for the day-to-day applications in advanced manufacturing, chemical industries and advanced applications need the better performing materials. SnO2 (wide band gap-3.27eV, n-type semiconductor) and Ni-doped SnO2 are the suitable materials for gas sensing in the fields of forward-looking technology. Pure and Ni-doped SnO2 particles were synthesized by sol-gel method and started with 0.2 mol of SnCl2, added with 2 ml of acetic acid, and pH controlled by the addition of 8 mol NaOH, till pH reaches desired value and Ni is doped. Finally washed, dried, and calcined at 400° C. The prepared pure and Ni(0.02 and 0.04 mol)-doped SnO2 nanostructures were characterized by XRD, EDAX, DSC, and SEM techniques. Average crystallite size is calculated by XRD and varied from 8 to 5 nm. Morphology shows difference, while the Ni concentrations changed. Particle size is estimated by transmission electron microscope (TEM), found to be 8–12 nm and well correlated with XRD analysis. The Energy gap is calculated with the UV–Vis spectrometer, and values are 3.21, 3.60, and 3.56 eV. Finally, the application part was carried out for NO2 gas sensing at a low level of 7–19 parts per million (PPM) at 40 °C, response and recovery times are 6 and 9 min respectively for all PPMs. Sensitivity of the samples of pure and Ni doped samples have 99 to 99.9 and 80 %. Pure and 0.02 mol Ni doped samples have the good achievement for sensitivity and 0.04 mol Ni doping has increase in conductance.

Preparation of the scattering layer based on SnO2 nanocrystals for dye sensitized solar cell application

Abstract In this work, SnO2 paste was prepared based on (0.1 and 0.12 g) of SnO2 nanoparticles. The SnO2 film was deposited using Screen printing and doctor blade techniques, which it employed as scattering layer in Dye-Sensitized Solar Cell (DSSC). The crystal structure, morphology, and thermal stability of the paste were investigated using XRD, FE-SEM, and TGA techniques. The DSSC parameters were achieved to examining the effect of scattering layer on performance of DSSC. The results showed a crystalline structure predominantly composed of rutile SnO2 crystals arranged in a tetragonal pattern, with individual crystallites measuring approximately 100 nanometers in size. SEM images depicted the surface of SnO2 resembling a sponge with fine pores facilitating dye adsorption and electron mobility. Moreover, a decrease in average particle size was observed with increasing dye concentration, with the average grain size of SnO2 particles being below 100 nanometers at lower dye concentrations. TGA measurements indicated a phase transition occurring around 400 °C.

Preparation and Characterization of Pyramids/Particles NiO/SnO2 Composite for Sorption and Separation of Molybdenum and Zirconium Ions from Some Synthetic Fission Products

AbstractPyramids/particles of NiO/SnO2 composite (NS7) was produced by applying the sol–gel autocombustion method. The produced composite was investigated using different techniques, X-ray diffraction, Fourier-transform infrared, Raman spectroscopy, scanning electron microscope, dynamic light scattering, ultraviolet–visible absorbance spectroscopy, and BET surface area then was applied for the adsorption and separation of molybdenum and zirconium ions from lanthanum, strontium, and cesium. 3D pyramids of NiO and particles of SnO2 are confirmed in the composite with a homogeneous mesoporous structure. The composite has good affinity for zirconium and molybdenum ions with fast kinetics and Qmax of 27.1 and 33.3 mg/g, respectively, low affinity for lanthanum, and negligible affinity for strontium and cesium. The sorption mechanism is physical sorption and endothermic in nature. The adsorbed Zr(IV), Mo(VI), and La(III) ions were separated using the desorption process as the following sequence: First, 95 ± 2% (14.3 ppm) of the loaded La was desorbed by washing with double distilled water. Then 96 ± 2% (41.3 ppm) of the loaded Zr was recovered by 1 M potassium chloride without interfering ions. Finally, 98 ± 2% (42.88 ppm) of Mo is desorbed by 1 M sodium acetate solution. The NS7 composite can be reused five times successfully.

Preparation and arc erosion mechanism of Ni skeleton reinforced Ag-based contact materials with CuO-coated SnO2

The Ag-SnO2 contact material is widely regarded as the most promising environmental friendly electrical contact material. However, during the make and break operations, SnO2 particles rising to the surface can cause increased contact resistance and temperature rise, which affects the service life of the contact material. In this study, a three-dimensional (3D) Ni skeleton reinforced Ag-based contact material with CuO-coated SnO2 are successfully fabricated via powder metallurgy technology. The basic physical properties of the novel contact material were tested and the microstructures and arc erosion morphologies were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The research demonstrated that the hardness and electrical conductivity of the novel contact material are 128.9 HV and 46 %IACS, respectively. It can be observed that the SnO2-rich phase is uniformly distributed in the Ag matrix without significant upward after arc erosion, which indicates that the SnO2@CuO core-shell structure effectively enhances the wettability between Ag and SnO2. Meanwhile, the study revealed that the Ni phase uniformly distributed at the interface of the Ag phase during the arc erosion process, indicating that the 3D Ni skeleton structure effectively impedes the expansion of the Ag molten pool and improves the anti-arc erosion performance.

Synergistic effect of grain size and surface oxygen vacancies for enhanced photoresponse properties of nanocrystalline SnO2 films

The photoresponse properties of nanocrystalline tin dioxide (SnO2) thin films with different grain sizes were systematically studied for fabricating transparent oxide-based ultraviolet (UV) photodetector. SnO2 nanoparticles were synthesized using the coprecipitation method and calcination temperatures were varied (400 °C–800 °C) to prepare SnO2 particles of different grain sizes (∼8 nm–∼42 nm). Subsequently, thin films of SnO2 nanoparticles were deposited using the spin-coating technique to fabricate UV photodetectors. The optical transparency of SnO2 thin films was improved by 10 % with the increasing grain size of the sample, while the band gap of the films was found to vary from 3.718 eV to 3.761 eV. The responsivity (Rλ) and the external quantum efficiency (EQE) of SnO2 based photodetector were noticeably large (Rλ = 200 mA/W and EQE = 90 %) in the UV range for devices with the smallest grain sizes (∼8 nm). Moreover, the same device exhibited a much faster photoresponse time (∼2 s) and a large photo-to-dark current ratio (∼103). The structural and spectroscopic studies on the SnO2 thin films revealed that the microscopic parameters like grain size, grain boundary potential, and surface oxygen vacancies play significant roles in modulating the optical properties and photoresponse of the nanocrystalline SnO2 thin films.

Interfacial engineering and defect passivation of SnO2 through agmatine sulfate in carbon-based perovskite solar cells

Electron transport layer has always played a crucial role in the performance of the perovskite solar cells (PSCs). Particularly, SnO2-based PSC has sparked considerable interest due to its superior properties. Even with such remarkable properties, certain challenges persist such as agglomeration of SnO2 particles which can lead to interfacial defects and poor morphology. To solve this problem, Agmatine Sulfate (AGTS) has been introduced as an interfacial modification agent which with the help of its active functional group including amide (-NH2) and hydroxyl (OH) has allowed to facilitate the interaction at the interface between SnO2 and perovskite. The interaction facilitates the growth of perovskite crystals while tuning the energy levels which has boosted the charge transfer capability of the layer. All these improvements in the properties have led to enhanced power conversion efficiency (PCE) from 11.17 % to 15.20 % for the encapsulated device. Furthermore, the modification also improved the long-term stability of the device as the AGTS-modified devices retained 87 % of their performance at 15–25 °C with humidity levels between 10 and 20 % for over a period of 31 days. Finally, the devices prepared with the AGTS also showed repeatability in their performance while boosting the overall performance of carbon-based PSCs (C–PSCs) and indicating a novel approach to not only increase but also accelerate the commercialization of C-PSC.

Tailored synthesis of a unique two-dimensional pretzel-like core-shell SnO2/C composite for improved lithium storage performance

In this research, a unique two-dimensional (2D) core-shell SnO2/C composite with a distinctive pretzel-like morphology was successfully synthesized using the tin-citrate complex as the tin source, and glucose as the carbon source through a hydrothermal synthesis, and followed by a high-temperature carbonization process. When assessed as an anode for lithium-ion batteries (LIBs), the composite demonstrated a significant specific capacity of 529 mAh g−1 at a current density of 200 mA g−1 after 100 cycles. Furthermore, it maintained ca. 200 mAh g−1 at a high current density of 1.6 A g−1, indicating excellent cycling stability and rate capability. The remarkable electrochemical performance can be ascribed to the well-dispersed nanoscale SnO2 particles within the amorphous carbon matrix, the distinctive core-shell structure and 2D pretzel-like conductive network. The prepared SnO2/C composite can be a promising alternative anode for future LIBs, offering higher energy density, prolonged cycle life, and faster charging capability compared to traditional graphite-based anodes.

Hole scavenger effect on hexagonal ZnO nanostructures decorated with SnO2 nanoparticles for generating high current densities via photoelectrochemical activity

This study investigated the effects of the heterostructure and interface kinetics on the photocurrents generated by ZnO-coupled SnO2 nanostructures. Electrochemical impedance spectroscopy was utilized to understand the nanostructure heterostructure and interface charge kinetics in a 0.1 M NaOH under a ON/OFF state; the lowest charge kinetic resistance of 370.84 Ω was attained for ZnO sample decorated with SnO2 particles in the light state, which is ten times lower than that of ZnO structures, with a current density of 0.94 mA cm−2. In addition, the effect of the applied potential on the charge production of all the electrodes was examined at an applied voltage of 0.55 V vs. reference electrode, which showed the maximum generation of induced-current density for ZnO nanostructures decorated with SnO2 particles compared with other pristine electrodes. Furthermore, the hole scavenger effect on the interface kinetics and photocurrent generation for all the photoelectrodes was investigated under similar conditions, such as without a scavenger and in the same electrolyte. All electrodes in the presence of the scavenger exhibited better resistance, charge transfer kinetics, and photocurrent densities than the electrodes without a scavenger. The maximum current density of 8.96 mA cm−2 was attained for ZnO nanostructures decorated with SnO2 nanoparticles. This was higher compared with other pristine electrodes with scavengers, owing to better charge migration and reduced recombination due to the hole scavenger.

A room-temperature ppb-level detection limit of NO2 sensor based on Cellulose/SnO2 heterojunction under UV illumination

In light of growing concerns over air pollution, particularly NO2 emissions from vehicular and industrial sources, there is a critical demand for advanced gas sensors. Traditional metal oxide semiconductors, while widely used, face challenges such as poor selectivity and high operating temperatures. In this work, we have achieved a high selectivity and room temperature NO2 gas sensor by composite of sponge-like porous cellulose with SnO2 nanoparticle. As a result, the gas sensor exhibits excellent performance in terms of high response (260.4 at 20 ppm), excellent selectivity and low detection limit (100 ppb) for NO2 gas, due to the unique sponge-like porous structure of cellulose with its high specific surface area facilitating the uniform distribution of SnO2 particles. This study not only highlights the superior sensing capabilities of cellulose-based sensors but also lays the foundation for further advancements in environmentally-friendly gas sensing applications.

Supernanoporous SnO2 particles and spheres as sustainable solar cell constituents

This study presents the synthesis and a comparative report of the properties of supernanoporous SnO2 particles SNSP (0D) supernanoporous SnO2 spheres SNSS (3D) formed with an assembly of SNSP with a view to examine their application as effectual photoanodes in sustainable solar energy conversion. Porosity imposed nanoparticles with extended surface area improve photon interaction and charge transfer by increasing the absorption of light, hence addressing the existing efficiency hurdles in solar cells. SNSP with particle size of ∼23 nm and SNSS with particle size and sphere size of ∼26 nm and ∼800 nm, respectively, were synthesized by treating SnCl4 via solvothermal process at different experimental conditions. Important aspects of the as-synthesized SNSP and SNSS samples, such as the crystal structure, particle size, optical behaviour, identification of elements present, were characterized by powder X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Ultra Violet Diffuse Reflectance Spectroscopy (UV-DRS) and Energy Dispersive Analysis X-ray (EDAX) Spectroscopy techniques. Field dependent dark and photoconductivity studies reveal significant rise in the photoconducting nature, opto-electrical and surface properties of SNSP and SNSS. Pore size distribution and specific surface area of SnO2 particles and spheres were measured by Brunauer-Emmett-Teller (BET) analysis. High Resolution Transmission Electron Microscopy (HRTEM) is performed to analyze the size and shape of the porous SnO2 particles and spheres and further to correlate the data derived from FESEM. From other prevailing applications of porosity imposed nanomaterials such as gas sensing, catalytic and photodegradation the innovation of this work is to depict the novelty of porous SnO2 particle and sphere with highlighting thermal stability to instigate into the charge transport property suitable for solar cell application. The results were analyzed evincing the photovoltaic properties of spheres over particles and hence the PSC constituent among SNSP and SNSS with better proficiency was identified as appropriate photoconducting medium for fabrication of sustainable photovoltaic cells.

Simultaneous Li-Doping and Formation of SnO2-Based Composites with TiO2: Applications for Perovskite Solar Cells.

Tin oxide (SnO2) has been recognized as one of the beneficial components in the electron transport layer (ETL) of lead-halide perovskite solar cells (PSCs) due to its high electron mobility. The SnO2-based thin film serves for electron extraction and transport in the device, induced by light absorption at the perovskite layer. The focus of this paper is on the heat treatment of a nanoaggregate layer of single-nanometer-scale SnO2 particles in combination with another metal-dopant precursor to develop a new process for ETL in PSCs. The combined precursor solution of Li chloride and titanium(IV) isopropoxide (TTIP) was deposited onto the SnO2 layer. We varied the heat treatment conditions of the spin-coated films comprising double layers, i.e., an Li/TTIP precursor layer and SnO2 nanoparticle layer, to understand the effects of nanoparticle interconnection via sintering and the mixing ratio of the Li-dopant on the photovoltaic performance. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM) measurements of the sintered nanoparticles suggested that an Li-doped solid solution of SnO2 with a small amount of TiO2 nanoparticles formed via heating. Interestingly, the bandgap of the Li-doped ETL samples was estimated to be 3.45 eV, indicating a narrower bandgap as compared to that of pure SnO2. This observation also supported the formation of an SnO2/TiO2 solid solution in the ETL. The utilization of such a nanoparticulate SnO2 film in combination with an Li/TTIP precursor could offer a new approach as an alternative to conventional SnO2 electron transport layers for optimizing the performance of lead-halide perovskite solar cells.

Earthworm excrete derived-enzyme enriched SnO2/g-C3N4 nanocomposite for near complete decomposition of toxic dye molecules

Enzymes derived from earthworm (Eudrilus eugeniae) excretes (vermiwash) were used as supporting bio-catalysts with SnO2/g-C3N4 nanocomposites for photocatalytic dye degradation of toxic organic dyes. The results were compared to those of the composite partners SnO2 and g-C3N4. The enzyme supported nanocomposite has superior photocatalytic efficiency of 95 %, 93 %, 83 % and 97 % against the test dyes Methylene Blue (MB), Malachite Green (MG), Methyl Orange (MO) and Rose Bengal (RB) whereas the partners SnO2 (62 %, 81 %, 36 % & 73 %) and g-C3N4 (76 %, 84 %, 80 % & 89 %) exhibited lower efficiencies. The enzymes phosphatase, amylase, urease and protease present in the synthesized nanocomposite play supporting role as co-catalyst in enhancing the photocatalytic ability of the nanocomposite. The mechanism involving the charge carrier recombination delay due to the formation of g-C3N4 sheets beneath the SnO2 particles is illustrated. The partnering mechanism with g-C3N4 having lower bandgap (2.8 eV) leads to a reduction in the bandgap from 3.5 eV for SnO2 to 2.6 eV for the nanocomposite making the nanocomposite as visible light responsive photocatalyst. The XRD, FTIR, SEM-EDX, UV–vis–NIR, XPS and DFT results support the discussion on photocatalytic mechanism. The near complete dye degradation is confirmed by phenotypic test on earthworm (Eudrilus eugeniae).

Demonstrating photocatalytic esterification as a potential strategy to improve the properties of feedstock oil derived from dairy waste scum for biodiesel production

The availability of quality feedstock for biodiesel production is challenging; and therefore, techniques to improve the quality of feedstock are highly desired, as they could be utilized to modify any feedstock and enhance the biodiesel production. Dairy waste scum oil (DWSO) is recently known to be a valuable feedstock for producing biodiesel. However, DWSO needs to go through an esterification process to reduce its high free fatty acid (FFA) content. To do this, herein, we have treated the DWSO using photocatalytic tin oxide (SnO2) particles under UV light irradiation and reduced the FFA content significantly compared to the conventional cumbersome acid-mediated esterification process. The synthesized catalyst is characterized for its structural, morphological, optical and surface properties using various characterization techniques. Parameters such as catalysts dosage, methanol to oil ratio, reaction time, and temperature involved in the photo-assisted esterification processes are optimized, and a mechanism for the photocatalytic esterification reaction is also proposed. Importantly, SnO2 particles also showed excellent reusability in the photo-assisted esterification process. Overall, the physiochemical and fuel properties of the photo-esterified DWSO-derived biodiesel are found to be improved compared to the biodiesel synthesized via conventional acid-esterified oil.

Combination of multiple routes to enhance DSSC performance: Flower-like structure of SnO2 as photoanode and modification with Ag nanoparticle

SnO2 is an attractive photoanode material for dye-sensitized solar cells (DSSCs), but it has many drawbacks and needs to be modified. In this study, flower-like SnO2 particles are firstly prepared by a simple one-step hydrothermal synthesis method respectively, and the effect of hydrothermal reaction time on the growth of the particles is explored. The morphological and structural characterisation reveals that the flower-like particles have a larger specific surface area can provide more adsorption sites for dye molecules and are more suitable for photoanode materials. Then the optimal flower-like SnO2 particles are selected to prepare the photoanode, which is also modified with different concentrations of Ag nanoparticles to successfully introduce the localized surface plasmon resonance (LSPR) effect, and the optimal modification concentration is explored. Conformal characterisation, dye adsorption and light absorption tests revealed that the modification of Ag nanoparticles not only optimises the photoanode conformal structure and improves the dye adsorption, but also works in conjunction with the LSPR effect to improve the light absorption and utilisation, thus increasing the cell efficiency. Many cell performances of DSSC are also greatly improved due to the above work, and the optimal cell performance of DSSC is achieved when the Ag nanoparticles doping concentration is 0.03 M. Compared with the pure flower-like SnO2-based photoanode DSSC, the short-circuit current density of the best Ag nanoparticle-modified DSSC is enhanced by 28.56% to 15.80 mA/cm2, and its efficiency is improved by 20.82%–5.92%.

Influence of different thermodynamic parameters on variation across the aerosol size spectrum

During a severe accident in a nuclear power plant, fission products can be released into the containment in the form of radioactive aerosols. The behavior of these aerosols is influenced by various thermodynamic parameters, including temperature, pressure, and relative humidity. Changes in these parameters can impact the aerosol size spectrum, leading to variation in aerosol transport and deposition. Having a comprehensive grasp of how thermodynamic parameters impact change in the aerosol size spectrum is crucial for managing and mitigating the consequences of a severe accident, as it allows for better prediction of aerosol behavior and appropriate interventions. A series of experimental works on in-/soluble aerosols and their mixtures has been carried out using the IN–EX facility located at the Forschungszentrum Juelich the Germany. The changes in the aerosol size spectrum of SnO2 , CsI and two different mass composition mixtures (SnO2 : CsI = 7:3 or 4:6) under various thermodynamic conditions are discussed and analyzed. The results show that increasing the temperature leads to a broader aerosol spectrum for SnO2 , but not for CsI aerosols. With the increasing pressure, the aerosol size spectrum shifts towards smaller particles for CsI, but not for SnO2 . Furthermore, increasing the relative humidity causes the aerosol size spectrum of both SnO2 and CsI particles to shift towards larger particles, whereas CsI particles are more pronounced. The behavior of such mixtures relies on the composition of the primary substance within it. These findings provide robust information for improving the strategies of severe accident management.

Tin-antimony/carbon composite porous fibers: electrospinning synthesis and application in sodium-ion batteries

In this work, tin-antimony/carbon composites porous fibers were successfully synthesized by an electrospinning method combined with two-step heat treatment processes, in which SnCl2 and SbCl3 were used as tin and antimony sources, and polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) were used as binders and pore-forming agents. The as-synthesized tin-antimony/carbon composites were systematically characterized by x-ray Diffraction (XRD), Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Energy-Dispersive Spectrometer (EDS), x-ray Photoelectron Spectroscopy (XPS), and Thermogravimetric Analysis-Differential Scanning Calorimetry (TG-DSC). The results indicate that the composite material consists of one-dimensional nitrogen-doped carbon porous fibers as the main matrix, with a three-dimensional network structure in which Sn, SnO2, and SnSb particles are encapsulated. Furthermore, the tin-antimony/carbon composites porous fibers were utilized as self-supported negative electrode for sodium-ion batteries. The results showed that the SNbM-2 sample electrode calcined at 800 °C demonstrated the best cycling stability and rate capability among all the sample electrodes, with a discharge capacity of 319.5 mAh·g−1 maintained after 100 cycles at a current density of 0.1 A·g−1. The excellent electrochemical performance of the SNbM-2 sample electrode is benefited from its unique porous structure and the carbon fiber network structure encapsulating Sn, SnO2, and SnSb particles, which could effectively shorten the Na+ ion transport distance and mitigate electrode volume expansion.

Optimization of Deposition Parameters of SnO2 Particles on Tubular Alumina Substrate for H2 Gas Sensing

Resistive gas sensors, which are widely used for the detection of various toxic gases and vapors, can be fabricated in planar and tubular configurations by the deposition of a semiconducting sensing layer over an insulating substrate. However, their deposition parameters are not often optimized to obtain the highest sensing results. Here, we have investigated the effect of deposition variables on the H2 gas sensing performance of commercially available SnO2 particles on tubular alumina substrate. Utilizing a tubular alumina substrate equipped with gold electrodes, we varied the number of deposited layers, rotational speed of the substrate, and number of rotations of the substrate on the output of the deposited sensor in terms of response to H2 gas. Additionally, the effect of annealing temperatures (400, 500, 600, and 700 °C for 1 h) was investigated. According to our findings, the optimal conditions for sensor fabrication to achieve the best performance were the application of one layer of the sensing material on the sensor with ten rotations and a rotation speed of 7 rpm. In addition, annealing at a lower temperature (400 °C) resulted in better sensor performance. The optimized sensor displayed a high response of ~12 to 500 ppm at 300 °C. This study demonstrates the importance of optimization of deposition parameters on tubular substrates to achieve the best gas sensing performance, which should be considered when preparing gas sensors.