Prepared SnO2 Nanoparticles Research Articles

Lead-free X-Ray shielding aprons using Zn-doped SnO2 epoxy nanocomposite: A promising alternative to traditional heavy and lead-based materials

This report describes the first use of SnO2 nanoparticles with Zn dopants as a light weight and lead-free material for X-ray shielding applications. The material is environmentally friendly and offers high X-ray attenuation properties, making it a promising alternative to traditional heavy and lead-based X-ray shielding materials. The Zn-doped SnO2 nanoparticles were prepared using a sol-gel synthesis technique. This approach enabled the creation of high-quality Zn-doped SnO2 nanoparticles that were then mixed with epoxy polymer and coated onto a nylon mixed rexine cloth with the help of the drop casting technique, and they were treated for X-ray shielding applications. Micro-sized PbO particles were mixed with epoxy resin and coated onto rexine cloth to compare the X-ray shielding properties of the Zn-doped SnO2 nanoparticle. The structural properties were evaluated through X-ray Diffraction (XRD) and Raman analysis showed that the prepared SnO2 nanoparticles were in a tetragonal crystal structure. When compared to pure SnO2, the crystallite size of Zn-doped SnO2 nanoparticles was reduced (23.5–18 nm). UV–Visible spectroscopy is used to calculate the bandgap, which is increased as dopant introduced (3.41–3.57 eV). The photoluminescent (PL) study showed where the oxygen vacancy defect peaks originate. The cross-section Scanning Electron Microscopy (SEM) mapping showed a good coating of Zn doped SnO2 nanoparticle on the rexine cloth. The X-ray shielding abilities were extensively researched using various methods including percentage of attenuation (98–80 %), exposure, half value layer (0.06–0.16 mm), linear attenuation coefficient (μ), and mass attenuation coefficient (8.29–3.32 cm2/g). The findings indicated that 2% Zn-doped SnO2 has outstanding X-ray shielding properties compared to undoped SnO2 and PbO based aprons, making it a potential alternative for lead-free aprons in X-ray shielding applications.

Effect of Oxygen Vacancy on the Crystallinity and Optical Band Gap in Tin Oxide Thin Film

Herein, we have prepared tin oxide (SnO2) nanoparticles (NPs), through a co-precipitation method, using SnCl2·2H2O dissolved in distilled water (DW) as a precursor. Then, the prepared NPs were heat treated in a muffle furnace, as a function of temperature, under an open atmosphere. The prepared SnO2 NPs were then re-dispersed in DW, followed by spray casting on a glass substrate, for preparing SnO2 thin films. The average thickness of the fabricated SnO2 thin films was 2.76 µm. We demonstrated a very clear variation in the structural, compositional, and morphological features of the different films (in particular, variation of the density of oxygen vacancies), which altered their electrical and optical properties. Raising the calcination temperature of the SnO2 thin films, from 250 °C to 650 °C, led to a monotonic reduction in the crystallite size, from 10.4 nm to 6.7 nm, and a decrease in the O/Sn ratio, from 5.60 to 4.79. A 14.5% decrease in the O/Sn ratio resulted in a decrease in the crystallite size by 3.7 nm (i.e., a 35.3% decrease in the NP size), and a decrease in the band gap of 0.11 eV. The lowering of the band gap, along with an increase in the oxygen vacancies in the films, accords well with previous studies. Besides, as the calcination temperature was raised, the refractive index and absorption coefficient values were also found to notably increase. Very interestingly, by simply altering the calcination temperature, we were able to produce SnO2 thin films with optical band gaps nearly equal to the fundamental band gap (2.96 eV), even though many earlier experimental studies had reported considerably greater values (3.36–4.24 eV). SnO2 thin films with lower oxygen vacancies exhibited relatively higher band gaps, which is likely to be favorable for the desired electron transport layer in perovskite solar cells.

Operando X-ray Absorption Spectroscopy Study of SnO2 Nanoparticles for Electrochemical Reduction of CO2 to Formate

Tin-based electrocatalysts exhibit a remarkable ability to catalyze CO2 to formate selectively. Understanding the size-property relationships and exploring the evolution of the active size still lack complete understanding. Herein, we prepared SnO2 nanoparticles (NPs) with a controllable size supported on commercial carbon spheres (SnO2/C-n, n = 1, 2, and 3) by a simple low-temperature annealing method. The transmission electron microscopy/scanning transmission electron microscopy images and fitting results of the small-angle X-ray scattering profile confirm the increased size of SnO2 NPs due to the increase of SnO2 loading. The catalytic performance of SnO2 has proved the size-dependent effect during the CO2 reduction reaction process. The as-prepared SnO2/C-1 displayed the maximum Faradic efficiency of formate (FEHCOO-) of 82.7% at -1.0 V versus reversible hydrogen electrode (RHE). In contrast, SnO2/C-2 and SnO2/C-3 with larger particle sizes achieved lower maximum FEHCOO- and larger overpotential. Moreover, we employed operando X-ray absorption spectroscopy to study the evolution of the oxidation state and local coordination environment of SnO2 under working conditions. In addition to the observed shifts of the rising edge of Sn K-edge X-ray absorption near-edge structure spectra to a lower energy side as the applied voltage decreases, the decreased coordination number of Sn in the Sn-O scattering path and the presence of Sn metal contribution in the extended X-ray absorption fine structure spectra verify the reduction of SnO2 to SnOx and metallic Sn.

Bio-Synthesized Tin Oxide Nanoparticles: Structural, Optical, and Biological Studies

This research was planned to synthesize a biological potent nanomaterials via an eco-friendly process to combat the diseases causing bacteria and the free radicals generated inside the body. For this purpose, a green synthesis process was employed to prepare SnO2 nanoparticles by utilizing leaf extract of Populus ciliate, and they were characterized via different physico-chemical techniques. The crystallite size of SnO2 nanoparticles was found to be 58.5 nm. The calculated band gap energy of SnO2 nanoparticles was 3.36 eV. The SnO2 nanoparticles showed 38, 49, 57, and 72% antioxidant activity at concentrations of 100, 200, 300, and 400 L with 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonicacid) (ABTS) assays. The antibacterial effects of prepared SnO2 nanoparticles were studied using the agar well diffusion method against Gram-positive bacteria (S. pyogene and S. aureus) and Gram-negative bacteria (K. pneumoniae and E. coli). Both the antioxidant activity and antibacterial activity were seen to increase with increasing the concentration of the nanoparticles.

Flower-like SnO2 Nanoparticle Biofabrication Using Pometia pinnata Leaf Extract and Study on Its Photocatalytic and Antibacterial Activities.

The present study reported biofabrication of flower-like SnO2 nanoparticles using Pometia pinnata leaf extract. The study focused on the physicochemical characteristics of the prepared SnO2 nanoparticles and its activity as photocatalyst and antibacterial agent. The characterization was performed by XRD, SEM, TEM, UV-DRS and XPS analyses. Photocatalytic activity of the nanoparticles was examined on bromophenol blue photooxidation; meanwhile, the antibacterial activity was evaluated against Klebsiella pneumoniae, Escherichia coli Staphylococcus aureus and Streptococcus pyogenes. XRD and XPS analyses confirmed the single tetragonal SnO2 phase. The result from SEM analysis indicates the flower like morphology of SnO2 nanoparticles, and by TEM analysis, the nanoparticles were seen to be in uniform spherical shapes with a diameter ranging from 8 to 20 nm. SnO2 nanoparticles showed significant photocatalytic activity in photooxidation of bromophenol blue as the degradation efficiency reached 99.93%, and the photocatalyst exhibited the reusability as the degradation efficiency values were insignificantly changed until the fifth cycle. Antibacterial assay indicated that the synthesized SnO2 nanoparticles exhibit an inhibition of tested bacteria and showed a potential to be applied for further environmental and medical applications.

Green synthesis of SnO2 nanoparticles using Delonix elata leaf extract: Evaluation of its structural, optical, morphological and photocatalytic properties

This research article reports the green synthesis of SnO2 nanoparticles and its structural, optical, morphological and photocatalytic behaviors has been achieved by using Delonix elata leaf extract. Three different synthesis routes (i.e., sonication, wet chemical, and microwave method) are employed to prepare SnO2 nanoparticles. A comparative analysis was performed on the main physical properties to get a broader understanding of the effect of processing parameters on prepared SnO2 nanoparticles. The prepared SnO2 nanoparticles were characterized using different techniques like TG, XRD, FESEM, EDX, FT-IR, UV–Vis, PSD, and BET surface area analysis. Furthermore, the application of the prepared SnO2 nanoparticles as photocatalyst was proceeded to degrade rhodamine B dye.

Sulfur dioxide gas sensing at room temperature based on tin selenium/tin dioxide hybrid prepared via hydrothermal and surface oxidation treatment

In this paper, a novel SnSe/SnO2 nanoparticles (NPs) composite has been successfully fabricated through hydrothermal method and surface oxidation treatment. The as-prepared sample was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). A series of morphological and structural characteristics confirm that the SnSe/SnO2 NPs composite shows a core–shell structure with a SnO2 shell with thickness of 6 nm. The prepared SnO2 NPs and SnSe/SnO2 NPs composite were applied as gas-sensing materials, and their gas-sensing properties were investigated at room temperature systematically. Experimental results show that the response value of the SnSe/SnO2 composite sensor toward 100 × 10–6 SO2 is 15.15%, which is 1.32 times higher than that of pristine SnSe (11.43%). And the SnSe/SnO2 composite sensor also has a detection limit as low as 74 × 10–9 and an ultra-fast response speed. The enhanced gas-sensing performance is attributed to the formation of p–n heterojunction between SnSe and SnO2 and the appropriate SnO2 shell thickness.

Green Synthesis of SnO2 Nanoparticles for Catalytic Degradation of Rhodamine B

A novel method was utilized for the synthesis of Tin (IV) oxide nanoparticles using the leaf extract of Carica papaya, Murraya Koenigii, Moringa Oleifera, and Acalypha Indica. The leaf extract acts as an excellent stabilizing, reducing and capping agent for nanoparticles. From XRD analysis, we found that the average crystallite size of SnO2 nanoparticles was equal to 5 nm (SnO2–CP), 19 nm (SnO2–MK), 38 nm (SnO2–MO), 11 nm (SnO2–AI). The band gap of the prepared SnO2 nanoparticles was in the range 2.8–3.1 eV. Further, the green synthesized SnO2 nanoparticles were tested for degradation of organic pollutant dye namely Rhodamine B in the presence of solar light. The effect of several parameters such as dye concentration, catalyst loading and pH level was studied. The results of optimization showed a maximum removal of color efficiency 86% at pH 8 for 1 × 10–5 M dye concentration and 100 mg catalysts. The pseudo-first-order kinetics was employed for all the catalysts.

A simple low cost method for synthesis of SnO2 nanoparticles and its characterization

Nanomaterials have gained a lot of interest due to their application in various fields. Tin oxide (SnO2) is an important n-type wide band-gap semiconductor in the field of gas sensing devices due to its chemical and mechanical stability. Here, SnO2 nanoparticles were synthesized by a simple chemical co-precipitation method followed by annealing the obtained nanoparticles at different temperatures. Several characterization techniques like powder X-ray Diffraction, Scanning Electron Microscope, Energy-Dispersive X-Ray spectroscopy, and Ultraviolet–Visible spectroscopy, Fourier Transform Infrared Spectroscopy were carried out to analyze the structure, size, morphology, elemental composition and optical properties of the prepared SnO2 nanoparticles.

Enhanced acetone detection performance using facile CeO2–SnO2 nanosheets

SnO2 and CeO2–SnO2 nanocomposites were fabricated using a facile hydrothermal method. The morphology and structure of the prepared SnO2 nanoparticles and CeO2–SnO2 nanosheets were characterized by X-ray diffraction, Raman spectra, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. Furthermore, the gas sensing properties of these nanocomposites were systematically investigated. Gas sensing results suggested that the SnO2 sensing composite with the optimal Ce content of 5 wt% possessed the highest sensor response of 47–750 ppm acetone at the optimum operating temperature of 280 °C. The sensor response improved over 4 times compared to that of the pure SnO2 nanoparticles. Meanwhile, the response time and recovery time of 5 wt% Ce doped SnO2 nanosheets sensor were about 9 s and 5 s, respectively. Moreover, the 5 wt% Ce doped SnO2 nanosheets sensor exhibited a high acetone selectively against methanal, methanol, ethanol and benzene. The enhanced acetone gas sensing performance of CeO2–SnO2 nanosheets can be related to the addition of CeO2 and consequently the modification of morphology and lesser oxidized surface of the nanocomposite. Thus, the facile CeO2–SnO2 nanosheets present significant promise for acetone detection applications.

Wavelength Dependent Ammonia Sensing Characteristics of SnO2 based Fiber Optic Sensor

SnO2 nanoparticles were synthesized by co-precipitation technique. The synthesized SnO2 nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and UV-visible diffused reflectance spectrometer (DRS). The XRD results addressed that the SnO2 nanoparticles was crystallized in rutile tetragonal structure. The SEM analysis confirms that the prepared nanopowder is composed of nanoparticles. Analysis of the DRS UV-Vis spectrum showed that the band gap of the synthesized SnO2 is to be ∼3.4 eV. The small cladding portion of the optical fiber was replaced with the synthesized nanoparticles. The ammonia sensing characteristics of the prepared SnO2 nanoparticles were analyzed for different wavelength ranges (red, yellow and blue) using polymethyl methacrylate fiber. It has been found that the synthesized SnO2 nanoparticles shows high sensitivity (∼23) in yellow wavelength range compared with red and blue wavelength ranges at room temperature.

Bio-active synthesis of tin oxide nanoparticles using eggshell membrane for energy storage application

Nano-sized tin oxide (SnO2) particles were synthesized using eggshell membrane (ESM), a natural bio-waste from the chicken eggshell. The crystallization of SnO2 into the tetragonal structure was confirmed from powder X-ray diffraction and the crystallite size ranged from 13 to 40 nm. Various shapes including rod, hexagonal and spherical SnO2 nanoparticles were observed from the morphological studies. The electrochemical impedance study revealed a lower charge transfer resistance (Rct) of 8.565 Ω and the presence of a constant phase element which arised due to surface roughness and porosity. Capacitive behavior seen in the cyclic voltammetry curve of the prepared SnO2 nanoparticles, find future applications in supercapacitors.

Effect of high Fe doping on Raman modes and optical properties of hydrothermally prepared SnO2 nanoparticles

Fe-doped tin dioxide nanoparticles SnO2:Fe (x%) with x ranging from 0 to 20 were elaborated by a performed hydrothermal method. A deep structural study on the obtained nanoparticles was carried out using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The XRD measurements revealed that the rutile structure of the SnO2 was kept even for high iron concentrations. It is also observed that when iron amount increases the grain size decreases and the band gap is obviously red shifted. HRTEM imaging shows a good crystallinity of the elaborated NPs and confirm the grain size magnitude deduced from XRD measurements. The Raman modes associated to ferric phases are absent in the Fe-doped spectra which is in agreement with the XRD and HRTEM results proving the formation of SnO2:Fe solid phase. The Raman A1g mode seems to be strongly affected by the morphology transformation undergone by SnO2 NPs and by the induced local symmetry break when introducing iron. Forbidden Raman phonon modes were detected and an enhancement of the (110) surface oxygen bridging seems to follow the iron doping. This latter structural feature seems to present a major contribution to the notable enhancement of hydroxyl groups’ adsorption on the Fe-doped SnO2 surface. The variation of the Urbach energy Eu with Fe amount is discussed and is found to be in accordance with the different interpretations. The PL spectra reveals that the UV-violet band of the SnO2 NPs was affected by iron presence and the induced non-systematic variation of this emission was discussed. A decrease in visible emission was noted when introducing iron revealing that Fe doping affects the density of singly charged oxygen vacancies.

Surface Decomposition of Dimethyl Methylphosphonate on SnO2 Nanoparticles: Role of Nanoparticle Size

We report the effect of SnO2 particle size on the adsorption behaviour of dimethyl methylphosphonate (DMMP). SnO2 nanoparticles with different particle sizes have been successfully synthesised by the reverse microemulsion method. Transmission electron microscopy and X-ray diffraction results were used to evaluate size distribution, shape and structure of the prepared SnO2 nanoparticles. The infrared spectra of adsorbed DMMP on SnO2 show that the adsorption is dissociative. In addition, it is shown that the size of SnO2 nanoparticles does not affect the reaction mechanism. Adsorption isotherms of DMMP show that by decreasing the size of SnO2 nanoparticles, the amount of DMMP adsorbed is increased. In addition, the calculated heats of adsorption of DMMP are increased as the SnO2 nanoparticle size decreases.

Expeditious synthesis of SnO2 nanoparticles through controlled hydrolysis and condensation of Tin alkoxide in reverse microemulsion

SnO2 is a very important material in many areas such as catalysis, gas sensors, and lithium ion batteries. In this study, we successfully prepared SnO2 nanoparticles from tin (IV) isopropoxide in reverse microemulsion, which is still a big challenge up to now due to the uncontrollable hydrolysis and condensation rate. The hydrolysis and condensation process was slowed down by diffusion limitation, i.e., increasing the viscosity of the reaction media by introducing PVA-224 to the reverse microemulsion. The strategy developed here is of general directive significance for preparing other metal oxide nanoparticles in reverse microemulsion from corresponding metal alkoxide precursors who have fast hydrolysis and condensation rate.

Structural, morphological and optical properties of tin oxide nanoparticles synthesized by sol–gel method adding hydrochloric acid

Tin oxide (SnO2) nanoparticles were synthesized by sol–gel method from cost-effective tin chloride (SnCl2·2H2O) and ethanol by adding ammonia solution. In a separate experiment, 4 ml of concentrated hydrochloric acid was added to this solution and SnO2 nanoparticles were prepared. Further SnO2 nanoparticles prepared without and with adding the hydrochloric acid were annealed at 200 °C for 1 h. The structural, morphological and optical properties of the synthesized SnO2 nanoparticles were studied by X-ray diffraction, scanning electron microscope, UV–Vis spectroscopy, Fourier transform infrared spectroscopy and fluorescence spectroscopy techniques. As prepared SnO2 nanoparticles by adding hydrochloric acid in the synthesis process reduced the crystallite size to ~4 from ~10 nm size of the annealed SnO2 nanoparticles prepared without adding hydrochloric acid. Annealing the SnO2 nanoparticles prepared adding hydrochloric acid improved the crystallite size from ~4 to ~4.5 nm. Addition of hydrochloric acid effectively modified the morphology of the SnO2 nanoparticles from agglomerated spherical structure to cauliflower-like structure. The band gap is increased due to decrease in the crystallite size in the sample prepared adding hydrochloric acid. Fluorescence spectrum exhibits a strong emission peak at 350 nm. Addition of HCl plays a major role to suppress the hydrolysis rate and leads to the formation of SnO2 nanoparticles.

Photocatalytic activity of SnO2 nanoparticles in methylene blue degradation

Nanosized SnO2 photocatalysts were prepared with a precipitation method and were characterized by performing transmission electron microscopy (TEM), powder X-ray diffraction (XRD), and X-ray absorption spectroscopy (XAS). The powder XRD results revealed that the SnO2 nanoparticles have a typical tetragonal rutile (cassiterite) structure and the average crystallite size was found to be approximately 4.5nm by using the Debye–Scherrer equation. The prepared SnO2 nanoparticles consist of agglomerated particles with a mean diameter of around 4–5nm according to the analysis of TEM images. The XAS data confirmed that the prepared samples have cassiterite structures with tin oxidation state of +4. The prepared SnO2 nanoparticles were found to exhibit approximately 3.8 times higher activity than bulk SnO2 in the photodegradation of methylene blue. On the basis of a trapping experiment, we developed a possible mechanism for the photodegradation on SnO2 nanoparticles.

One-step hydrothermal synthesis of tin dioxide nanoparticles and its photocatalytic degradation of methylene blue

A simple hydrothermal method was developed for the size-controlled synthesis of tin dioxide (SnO2) nanoparticles, using SnCl4·5H2O, ethylenediamine and hydrazine. The molar ratio of the reactants, temperature, reaction time and the surfactant were changed in order to investigate the effect of preparation parameters on the morphology and particle size of SnO2. According to scanning electron microscopy (SEM) results, ethylenediamine and hydrazine can control the particle growth and play an important role in formation of SnO2 nanostructures. The prepared SnO2 nanoparticles were characterized extensively by means of X-ray diffraction, energy-dispersive X-ray spectroscopy, SEM, transmission electron microscopy, Fourier transform infrared spectroscopy and diffuse reflectance spectroscopy. Besides, the photocatalytic properties of as-synthesized SnO2 nanoparticles have been evaluated for the degradation of methylene blue under UV light irradiation.

SnO 2 纳米颗粒的制备及其发光性能

用大分子网络凝胶法合成了氧化锡(SnO2)纳米颗粒。X射线衍射(XRD)结果表明,合成的SnO2纳米颗粒具有四方金红石结构,不含任何杂质相。扫描电镜(SEM)观察发现,制得的SnO2纳米颗粒形貌规整、呈类菱形。荧光光谱结果表明,在326 nm波长的光激发下,其荧光光谱由四个主发射带组成,其峰值分别位于379,417,450,470 nm。用230 nm波长的光激发,得到一个740 nm的荧光发射峰。基于实验结果,探讨了纳米SnO2的形成机理和发光机制。

Size-controlled synthesis of SnO2 nanoparticles using reverse microemulsion method

Tin oxide nanoparticles were prepared using an ionic surfactant (sodium dodecyl sulfate) and tin (IV) chloride as an inorganic precursor via the reverse microemulsion method. The size of the nanoparticles is controlled by variation of water-to-surfactant ratio. Eliminating of surfactant in prepared nanoparticles was confirmed by the infrared spectroscopy after sequential calcinations. Transmission electron microscopy, surface area, pore volume, average pore diameter, pore size distribution and X-ray diffraction results were used for evaluation of size distribution, shape and structure of prepared SnO2 nanoparticles. Transmission electron micrographs confirmed that the obtained materials are spherical nanoparticles. The X-ray diffraction results show the crystalline phases of all samples are SnO2 with tetragonal structured crystal. In addition, the X-ray diffraction and transmission electron microscopy data showed that the size of SnO2 nanoparticles decreased with decreasing the water-to-surfactant ratio.