SnO2 Research Papers - Academia.edu (original) (raw)

In this study, synthesis of novel binary chitosan-SnO 2 nanocomposites is reported. Different physical and chemical techniques were used to characterize and analyze the characteristics of the chitosan-SnO 2 nanocomposites as... more

In this study, synthesis of novel binary chitosan-SnO 2 nanocomposites is reported. Different physical and chemical techniques were used to characterize and analyze the characteristics of the chitosan-SnO 2 nanocomposites as photocatalysts. The prepared novel photocatalysts were used to degrade the model dyes such as methyl orange (MO) and rhodamine B (RhB) under different wavelengths (254, 310 and 365 nm) of UV light. The photocatalytic degradation results suggest that the prepared binary chitosan-SnO 2 (50:50) nanocomposite shows superior degradation efficiency compared with pure SnO 2 and binary chitosan-SnO 2 (75:25) nanocomposite owing to its high crystallinity, high surface area, and small particle size. It was also observed that chitosan-SnO 2 (50:50) nanocom-posite under different wavelengths (254 nm, 310 nm, and 365 nm) of UV light showed highest photocatalytic degradation of methyl orange and rhodamine B at 365 nm irradiation.

We report results on the electronic, vibrational, and optical properties of SnO2 obtained using first-principles calculations performed within the density functional theory. All the calculated phonon frequencies, real and imaginary parts... more

We report results on the electronic, vibrational, and optical properties of SnO2 obtained using first-principles calculations performed within the density functional theory. All the calculated phonon frequencies, real and imaginary parts of complex dielectric function, the energy-loss spectrum, the refractive index, the extinction, and the absorption coefficients show good agreement with experimental results. Based on our calculations, the SnO2 electron and hole effective masses were found to be strongly anisotropic. The lattice contribution to the low-frequency region of the SnO2 dielectric function arising from optical phonons was also determined resulting the values of ɛ 1⊥latt(0) = 14.6 and ɛ 1∥latt(0) = 10.7 for directions perpendicular and parallel to the tetragonal c-axis, respectively. This is in excellent agreement with the available experimental data. After adding the electronic contribution to the lattice contribution, a total average value of ɛ1(0) = 18.2 is predicted for the static permittivity constant of SnO2.

Tin(IV) oxide nanoparticles (SnO2 NPs) have attracted great attention in various fields such as environmental remediation, sensing, catalysis, and lithium ion batteries. This led to an intense development of different synthetic pathways... more

Tin(IV) oxide nanoparticles (SnO2 NPs) have attracted great attention in various fields such as environmental remediation, sensing, catalysis, and lithium ion batteries. This led to an intense development of different synthetic pathways for production of SnO2 NPs. At present, production of SnO2 NPs depends largely on methods that involve toxic chemicals and harsh reaction conditions, which have been identified as a major drawback and potential threats to human health and the environment. Alternatively, green synthesis has gained popularity, as it is eco-friendly and cost-effective and generates minimal waste. This paper focuses on green biosynthesis of SnO2 NPs using various plants and their different plant parts, including an evaluation of their potential applications. This work also emphasizes the effects of plant extracts and solvents on the size, morphology, and other properties of the synthesized SnO2 NPs.

A green, phytogenic and cost effective synthesis of tin oxide nanoparticles (SnO 2 NPs) using aqueous leaf extract of Tradescantia spathacea is reported. The structural, surface morphological and optical studies have been performed using... more

A green, phytogenic and cost effective synthesis of tin oxide nanoparticles (SnO 2 NPs) using aqueous leaf extract of Tradescantia spathacea is reported. The structural, surface morphological and optical studies have been performed using X-ray diffraction (XRD), Fourier-Transform Infrared spectroscopy (FT-IR), Scanning Electron mi-croscopy (SEM), UV-visible diffuse reflectance spectroscopy (UV-vis-DRS), photoluminescence (PL), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET). XRD pattern shows SnO 2 with tetragonal structure of crystallite size ranging 9-22 nm. The FTIR spectra exhibits the presence of hydroxyl groups, amines, alkenes and phenols from the aqueous leaf extract which are responsible for the synthesis of narrow band gap SnO 2 NPs. The SEM analysis suggests slight agglomeration morphology with particle size in the range of 46-89 nm. The band gap energy obtained was in range of 2.51-3.3 eV. Photoantioxidant activities of SnO 2 NPs in the dark and under visible light illumination were carried out. The SnO 2 NPs showed enhanced photoantioxidant activities under visible light irradiation.

Nanocrystalline SnO2 was prepared by the co-precipitation method and doped with CuO. Crystallite sizes were estimated by Scherrer formula to be of the order of 90 nm and lesser. A.C. conduction behaviour of the samples has been described... more

Nanocrystalline SnO2 was prepared by the co-precipitation method and doped with CuO. Crystallite sizes were estimated by Scherrer formula to be of the order of 90 nm and lesser.
A.C. conduction behaviour of the samples has been described by the different hopping processes. From impedance analysis multi-relaxation processes in the samples are evident. Shrinkage of Cole–Cole plots with increase in temperature is also observed in our case which shows role of grain and grain boundary effects in the conduction mechanism with rise in temperature. Dielectric constant decreases with frequency but
increases with rise in temperature which is governed by different components of polarizability (deformational and relaxational polarization). Dielectric constant increases
with rise in temperature but at higher frequency range it takes constant value. Impedance analysis is used to explain the effects of grain and grain boundary on transport mechanism
of undoped and CuO modified SnO2 nanoparticles.

Ag-SnO2 nanocomposites (1 mM and 3 mM) were synthesized in water at room temperature using an electrochemically active biofilm. The resulting nanocomposites were characterized by X-ray diffraction, transmission electron microscopy,... more

Ag-SnO2 nanocomposites (1 mM and 3 mM) were synthesized in water at room temperature using an electrochemically active biofilm. The resulting nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, diffuse reflectance spectroscopy, photoluminescence spectroscopy and X-ray photoelectron spectroscopy. The Ag-SnO2 nanocomposites exhibited enhanced photocatalytic activity under visible light irradiation for the degradation of methyl orange, methylene blue, 4-nitrophenol and 2-chlorophenol compared with pure SnO2 nanostructures. Photoelectrochemical measurements, such as electrochemical impedance spectroscopy, linear scan voltammetry and differential pulse voltammetry in the dark and under visible light irradiation, further supported the visible light activity of the Ag-SnO2 nanocomposites. These results showed that the Ag nanoparticles induced visible light activity and facilitated efficient charge separation in the Ag-SnO2 nanocomposites, thereby improving the photocatalytic and photoelectrochemical performance.

Tin dioxide (SnO2) and cobalt and nickel co-doped-SnO2 (Co,Ni)-SnO2 nanoparticles (NPs) have been synthesized via phytogenic and green method using an aqueous leaf extract of Tradescantia spathacea. The structural, optical and surface... more

Tin dioxide (SnO2) and cobalt and nickel co-doped-SnO2 (Co,Ni)-SnO2 nanoparticles (NPs) have been synthesized via phytogenic and green method using an aqueous leaf extract of Tradescantia spathacea. The structural, optical and surface morphological studies were analyzed using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV–vis diffuse reflectance spectrophotometer (UV–vis DRS), Photoluminescence spectroscopy (PL), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and BET. Powder XRD data revealed tetragonal rutile structure of SnO2 in which the crystallite size was in the range of 13–22 nm. The attachment of organic compounds on the surface of NPs was confirmed by FTIR. UV–vis DRS showed the red-shift to visible light in which the reduction of band gap was confirmed by Valence band X-ray photoelectron spectroscopy (VB-XPS). The PL intensity was reduced indicating the successful incorporation of Co and Ni dopants into SnO2 lattice. The photoantioxidant activities of the SnO2 and (Co,Ni)-SnO2 NPs were enhanced under visible light. Similarly, the photocatalytic conversion of 4-nitrophenol to 4-nitrophenolate ions was also enhanced under the visible light irradiation.

In planar perovskite solar cells (PSCs), engineering the extraction and recombination of electron-hole pairs by modification of the electron transport layer (ETL)/perovskite interface is very vital for obtaining high performance. The main... more

In planar perovskite solar cells (PSCs), engineering the extraction and recombination of electron-hole pairs by modification of the electron transport layer (ETL)/perovskite interface is very vital for obtaining high performance. The main idea here is to improve properties of the TiO 2 /perovskite interface by inserting an ultra-thin layer (UTL) of WO 3 or SnO 2 with the thickness of less than 10 nm by RF magnetron sputtering method. The structural and electrical characteristics of the samples were tested by XRD, AFM, FE-SEM, Mott-Schottky analysis, UV-Vis spectroscopy, J-V characterization and electrochemical impedance spectroscopy (EIS). It was found that the bilayer structured ETLs exhibit advantages of high electron extraction and low interfacial recombination together mainly based on a more effective energy level alignment. The best performance here belongs to the cell with TiO 2 /SnO 2 bilayer by which an improved efficiency exceeding 12% was achieved for the planar PSCs. The role of SnO 2 and WO 3 UTLs was also modeled using SCAPS-1D software. This simulation supported the experimental results and was used to interpret the photovoltaic behaviors of the fabricated devices based on defect characteristics. The present work proposes a simple and promising method to make photovoltaic devices with desirable charge transport and recombination properties.

This paper reports a novel one-pot biogenic synthesis of Au–SnO2 nanocomposite using electrochemically active biofilm. The synthesis, morphology and structure of the as-synthesized Au–SnO2 nanocomposite were in-depth studied and confirmed... more

This paper reports a novel one-pot biogenic synthesis of Au–SnO2 nanocomposite using electrochemically active biofilm. The synthesis, morphology and structure of the as-synthesized Au–SnO2 nanocomposite were in-depth studied and confirmed by UV-vis spectroscopy, photoluminescence spectroscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. It was observed that the SnO2 surface was decorated homogeneously with Au nanoparticles. The photoelectrochemical behavior of the Au–SnO2 nanocomposite was examined by cyclic voltammetry, differential pulse voltammetry, electrochemical impedance spectroscopy, and linear sweep voltammetry in the dark and under visible light irradiation. Visible light-induced photoelectrochemical studies confirmed that the Au–SnO2 nanocomposite had enhanced activities compared to the P–SnO2 nanoparticles. The Au–SnO2 nanocomposite was also tested for the visible light-induced photocatalytic degradation of Congo red and methylene blue, and showed approximately 10 and 6-fold higher photocatalytic degradation activity, respectively, compared to P–SnO2. These results showed that the Au–SnO2 nanocomposite exhibits excellent and higher visible light-induced photoelectrochemical and photocatalytic activities than the P–SnO2 nanoparticles, and can be used for a wide range of applications.