Chloride Pentahydrate Research Articles

Sensing analysis of polyaniline – stannous chloride pentahydrate composite of CO2 gas sensors

ABSTRACT In this experimental work, the composite of polyaniline-stannous chloride pentahydrate (PSCL) was synthesized at room temperature through polymerization using FeCl3 as an oxidant. The sensing was carried out at room temperature for a 150 ppm concentration of CO2 gas. The PSCL composite was coated on a glass substrate. The PSCL composite was characterized by XRD, FTIR, and Impedance spectroscopy analysis. XRD and FTIR confirm the formation of SnO2 particles in composites. The ideal capacitor will have phase angle at −90° which is shown by PSCL (10% and 20%) composites which indicate that they have lower ionic permeability and show there insulating properties. Whereas composites PSCL (5% and 15%) at low frequency show high ionic permeability, as they have phase angle near to −45° which makes them poor insulators. The response and recovery times of composites are [130 s, 31 s], [142 s, 556 s], [134 s, 98 s], and [113 s, 90 s] for PSCL 5%, 10%, 15%, and 20%. PSCL 15% shows better sensitivity toward CO2 gas at room temperature. PSCL composites show complete reproducibility. The migration of electron between the p-n junction formed in the composite and concentration of SnCL4. 5 H2O in the PSCL composite make it sensitive toward exposed CO2 gas.

Synthesis of Fe2O3@SnO2 Core‐shell Nanocomposites via Thermal Decomposition Route and their Application as an Adsorbent

AbstractIn the current study, a thermal decomposition approach has been used to synthesize Fe2O3@SnO2 core‐shell nanocomposites in which Fe2O3 microsphere is the core and SnO2 is the shell. The thickness of shell (SnO2) is altered by varying amount of tin chloride pentahydrate (precursor of SnO2). Various characterization techniques were used to prove successful formation of Fe2O3@SnO2 core‐shell nanocomposites. XRD results confirm the presence of SnO2, α‐Fe2O3, and Fe3O4 in the calcined Fe2O3@SnO2 core‐shell nanocomposites. FE‐SEM and TEM studies reveal uniform deposition of SnO2 nanoparticles over the iron oxide microspheres. XPS analysis demonstrates the presence of Sn4+, Fe2+, Fe3+, and O2− in the Fe2O3@SnO2 core‐shell nanocomposites. Optical studies show that the Fe2O3@SnO2 core‐shell nanocomposites absorb in UV and visible regions. M−H studies on Fe2O3@SnO2 core‐shell nanocomposites indicate weak ferromagnetic and superparamagnetic behaviour of the nanocomposites at 5 K and 300 K, respectively. From M−T measurements, pure α‐Fe2O3 shows characteristic Morin transition (Tm), but the Fe2O3@SnO2 core‐shell nanocomposites do not show such transition. The Fe2O3@SnO2 core‐shell nanocomposites were explored as adsorbent for the removal of congo red (CR) from an aqueous solution.

A new green system of biogenic dendritic fibrous Dy2Sn2O7 for production of dimethyl carbonate from carbon dioxide

Biogenic dendritic fibrous Dy2Sn2O7 (Dy2Sn2O7 BDF) were greenly generated in the attendance of Desulfovibrio alaskensis G20 from tin(IV) chloride pentahydrate and Dy(NO3)3·5 H2O as Sn and Dy sources. The anatomical analysis of the specimen verified the generation of Dy2Sn2O7 BDF in the scope of 300 nm. Specimens created with a Desulfovibrio alaskensis G20 was investigated by employing different approaches. The properties of Dy2Sn2O7 BDF as a nanocatalyst were determined by EDS, TGA, TEM, XRD, and SEM. Due to the high ionic internal character, high mechanical and thermal sustainability, and persistent colloidal stability, the system can be deemed as an ideal nanocatalyst by deploying the host-guest method. Carbon dioxide was converted to dimethyl carbonate products. The products were effortlessly separated from the green medium, and Dy2Sn2O7 BDF was reutilized for several runs without a notable drop in catalytic selectivity and activity.

Synthesis of SnO2-Ag nanocomposites via thermal decomposition method and their application for catalytic reduction of 4-nitrophenol and photocatalytic degradation of congo red

The discharge of untreated effluents containing toxic chemicals such as dyes into an aquatic environment disrupts ecological balance. Metal oxide-based nanocomposites can be used as photocatalyst to effectively remove organic dyes from waste water. In the present study, using a novel thermal decomposition approach, synthesis of SnO2-Ag nanocomposites has been achieved using tin chloride pentahydrate and silver salicylate ([Ag(HSal)]) as precursors. The particle size of Ag in the SnO2-Ag nanocomposites could be controlled by changing the amount of [Ag(HSal)] used during the synthesis. The presence of SnO2 and Ag nanoparticles in the SnO2-Ag nanocomposites was confirmed using powder X-ray diffraction (XRD). The purity of SnO2-Ag nanocomposites was proved by Fourier transform infrared (FT-IR) spectroscopy. The presence of Sn4+, Ago, surface hydroxyls and lattice oxygen was confirmed by XPS studies. The SnO2-Ag nanocomposites absorb in UV and visible regions. The SnO2-Ag nanocomposites perform as better catalyst for the photocatalytic degradation of congo red (CR) compared to the constituents. The nanocomposites show faster kinetics (within 30 minutes) as compared to the previously reported SnO2 based systems in the literature. The SnO2-Ag nanocomposites were also explored for catalytic degradation of 4-nitrophenol (4-NP) in an aqueous solution.

The influence of different radiopacifying agents on hermetical sealing ability of calcium silicate and calcium aluminate dental cements

This study presents technological process for obtaining strontium enriched calcium silicate based dental ceramics and testing their microstructural and chemical properties. In brief, the influence of different radiopacifiers on microstructural properties of calcium-silicate (CaSi) and calcium-aluminate (CaAl) dental ceramics was evaluated. For synthesis of CaSi-based ceramics, calcium chloride pentahydrate (CaCl2?5H2O) and silica sol obtained by hydrothermal treatment were used. CaSi+barium-sulphate (BaSO4), CaSi+bismuth-oxide (Bi2O3), CaAl+zirconium-dioxide (ZrO2), CaAl+strontium-carbonate (SrCO3), CaAl+strontium-fluoride (SrF2),pure CaSi, pure CaAland mineral trioxide aggregate (MTA) (control material) were used. The wettability, surface free energy (SFE), microporosity, nano-porosity and micro-gap size between the material and tooth root canal were evaluated. There was no difference in total SFE among tested cements (p<0.05), while CaSi+BaSO4, CaAl+SrCO3 and CaAl+SrF2 experienced superior wetting than other cements (p<0.05). The highest microporosity was observed in CaAl, whilst adding radiopacifiers into it decrease cements microporosity (p<0.05). The lowest nanoporosity was found for CaAl+ZrO2. The gap size was not statistically different among tested ceramics (p>0.05). Altogether, strontium containing radiopacyfiers result in improved microstructural characteristics of dental ceramics.

Aquilaria malaccensis and Pandanus amaryllifolius mediated synthesis of tin oxide nanoparticles: The effect of the thermal calcination temperature

The conventional methods to produce beneficial SnO2 Nps are tedious, expensive and harmful. Having this, the researcher has introduced a green synthesis technique that offers simplicity, non-toxic and economical techniques. In this study, the bioactive compound in A. malaccensis and P. amaryllifolius leaves was utilized to produce SnO2 Nps. The leaves extract was mixed with tin (iv) chloride pentahydrate solution, followed by a drying and calcination process ranging from 600, 700 and 800 °C. XRD results showed the impact of the temperature increment on the crystallinity characteristics, whereby the diffraction peaks were sharpened and intense as temperature arose and the average crystallite sizes of SnO2 Nps were found to be 6.3 nm and 10.5 nm from both leaves. The morphological images were spherical with regularities and tended to be grown to spherical grain when introduced to higher temperatures. UV–vis diffuse reflectance analysis revealed a higher surface-to-volume ratio and excellent light-harvesting manifested by SnO2 Nps mediated from P. amaryllifolius, resulting in 86 % of reflectance value, slightly higher than former nanoparticles that obtained 46 %. The rising temperature in the calcination led to the decrease of the energy band gap for SnO2 Nps prepared using A. malaccensis leaves extracts, as it is believed quantum size might be of influence. From the FTIR result, the drying process at 50 °C for the colloidal mixture apparently pre-calcined the solid particle, but eventually, the low temperature could not assist the nucleation of the SnO2 Nps growth. Somehow, the application of calcination temperature to the colloidal particle suppressed all the organic moiety, which furnished pure SnO2 Nps as the product. By having a good result for reflectance and band gap, the produced SnO2 Nps is best to be suggested for catalytic application, especially for water remediation.

Synthesis of SnS2/Carbon Quantum Dots/g‐C3N4 Composite and Its Photocatalytic Property

Photocatalytic degradation of organic pollutants is considered an ideal method to solve the global environmental pollution problem. In this method, photocatalytic materials are regarded as the key factor. As an n‐type photocatalytic material, graphitic carbon nitride (g‐C3N4) has attracted much attention due to its suitable bandgap, nontoxicity, and high photostability. However, g‐C3N4 still has defects such as insufficient visible light absorption, low specific surface area, and easy recombination of photogenerated electron–hole pairs, which lead to the poor photocatalytic performance of g‐C3N4. Herein, to solve the above problems, thiourea, lemon juice, and tin chloride pentahydrate are used as precursors, while carbon quantum dots (CQDs) are used as electron mediators, and the third phase SnS2 is introduced by a hydrothermal and ultrasonic composite method. SnS2/CQDs/g‐C3N4 composites with Z‐type heterojunction are successfully prepared. The results show that the SnS2/CQDs/g‐C3N4 has a 2D0D2D structure, which effectively inhibits the recombination of photogenerated electron–hole pairs, making the material have better photocatalytic degradation activity for Rhodamine B (RhB). When the mass ratio of SnS2 is 15%, the photocatalytic degradation efficiency of RhB by the composite reaches the best, which is 87.8%. After four cycles, the photocatalytic degradation efficiency of the 15% SnS2/CQDs/g‐C3N4 composite still remains at 82.9%.

Low pH nasal rinse solution enhances mupirocin antimicrobial efficacy.

Chronic rhinosinusitis (CRS) is a common condition negatively impacting a patient's quality of life. It has been hypothesized that bacterial biofilms are involved in the pathogenesis of CRS due to their persistence and difficulty to eradicate with conventional antibiotic therapy. Hence, the topical delivery of antibiotics via nasal rinse solution has gained a lot of attention due to the ability to deliver higher local concentrations, with less systemic absorption and side effects. This study investigates the efficacy of mupirocin dissolved in the 3 most commonly used sinus rinses in Australia Neilmed (isotonic saline), Flo Sinus Care (sodium chloride, sodium bicarbonate, potassium chloride, glucose anhydrous and calcium lactate and Pentahydrate) and FloCRS (sodium chloride, potassium chloride and xylitol). Planktonic and biofilm cultures of S. aureus (ATCC25923, 2 methicillin-resistant S. aureus (MRSA) (C222 and C263), and 2 methicillin-susceptible S. aureus (MSSS) (C311 and C349) clinical isolates) were treated with mupirocin dissolved in three sinus rinses (Neilmed, Flo Sinus Care and FloCRS with different pH). To establish whether pH was a significant factor in determining antibiotic activity, experiments with Flo CRS were performed both at pH 5.64 and elevated pH 7.7. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for planktonic cells. The biofilm biomass and metabolic activity were assessed by using crystal violet assay and alamarBlue assay respectively. The combination of mupirocin in low pH (pH 5.64) sinus rinse (FloCRS) had the highest efficacy in reducing the growth of S. aureus in both the planktonic and biofilm forms. Mupirocin diluted in FloCRS (pH 5.64) showed a significantly higher reduction in both biomass and metabolic activity than that was observed when mupirocin was diluted in Neilmed, Flo Sinus Care or FloCRS (pH 7.7). The choice of irrigant solution for topical mupirocin delivery appears to be important for antimicrobial activity. The delivery of mupirocin via low pH FloCRS could be useful in eliminating S. aureus biofilms present on the sinus mucosa of patients with CRS.

Low pH nasal rinse solution enhances mupirocin antimicrobial efficacy

Background: Chronic rhinosinusitis (CRS) is a common condition negatively impacting a patient’s quality of life. It has been hypothesized that bacterial biofilms are involved in the pathogenesis of CRS due to their persistence and difficulty to eradicate with conventional antibiotic therapy. Hence, the topical delivery of antibiotics via nasal rinse solution has gained a lot of attention due to the ability to deliver higher local concentrations, with less systemic absorption and side effects. This study investigates the efficacy of mupirocin dissolved in the 3 most commonly used sinus rinses in Australia Neilmed (isotonic saline), Flo Sinus Care (sodium chloride, sodium bicarbonate, potassium chloride, glucose anhydrous and calcium lactate and Pentahydrate) and FloCRS (sodium chloride, potassium chloride and xylitol). Methods: Planktonic and biofilm cultures of S. aureus (ATCC25923, 2 methicillin-resistant S. aureus (MRSA) (C222 and C263), and 2 methicillin-susceptible S. aureus (MSSS) (C311 and C349) clinical isolates) were treated with mupirocin dissolved in three sinus rinses (Neilmed, Flo Sinus Care and FloCRS with different pH). To establish whether pH was a significant factor in determining antibiotic activity, experiments with Flo CRS were performed both at pH 5.64 and elevated pH 7.7. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for planktonic cells. The biofilm biomass and metabolic activity were assessed by using crystal violet assay and alamarBlue assay respectively. Results: The combination of mupirocin in low pH (pH 5.64) sinus rinse (FloCRS) had the highest efficacy in reducing the growth of S. aureus in both the planktonic and biofilm forms. Mupirocin diluted in FloCRS (pH 5.64) showed a significantly higher reduction in both biomass and metabolic activity than that was observed when mupirocin was diluted in Neilmed, Flo Sinus Care or FloCRS (pH 7.7). Conclusion: The choice of irrigant solution for topical mupirocin delivery appears to be important for antimicrobial activity. The delivery of mupirocin via low pH FloCRS could be useful in eliminating S. aureus biofilms present on the sinus mucosa of patients with CRS.

Investigation of the influence of calcination temperature on morphology and structure of electrospun 1D SnO2 nanostructures

The aim of the study was to manufacture the SnO2 one-dimensional nanostructures via the sol-gel technique and electrospinning methods from a solution of polyvinylpyrrolidone (PVP), tin chloride pentahydrate (SnCl4-5H2O), N, N-dimethylformamide (DMF) and ethanol (EtOH). The as obtained fibrous mats consisting of polymer and precursors particles were subjected to the heat treatment in air in the following temperatures 500, 600 °C to obtain pristine tin oxide nanowires. The scanning electron microscope (SEM) was used to determine the effect of calcination temperature on the morphology and structure of produced 1D SnO2. The energy dispersive spectrometry (EDX) and Fourier-Transform Infrared spectroscopy (FTIR) were performed to investigate the chemical composition and structure of manufactured nanomaterials, respectively.

Impact on Anode Performance of Lithium-Ion Batteries by Deep Cryogenic Treated SnSb/C Nanofiber Derived From Inorganic Precursors

Abstract The major obstacle prohibiting the practical application of Sn-based anodes is drastic volume variation during cycling processes. Here, polyacrylonitrile (PAN) was acted as a carbon source, and stannic chloride pentahydrate (SnCl4·5H2O) and antimony chloride (SbCl3) were used as SnSb precursors. SnSb/C nanofibers were prepared via simple electrospinning, deep cryogenic treatment, and carbonization, and it is applied in anode materials for lithium-ion batteries (LIBs) to achieve excellent cycle performance (115.5% capacity retention for 100 cycles). The improvement of electrochemical performance is mainly attributed to the synergistic effect of deep cryogenic treated special SnSb/C nanofibers precursor. In the deep cryogenic treatment process, the crystalline water in the precursor has a pore-forming effect, and the porous nanofiber structure leads to the phenomenon of capacity increase. The above results indicate that comprehensive consideration of deep cryogenic treatment and nanofiber precursors is a new idea to enhance the electrochemical performance of LIBs anode materials.

Two Dimensional Mxene (Ti3C2) Decorated By SnO2 Nanocrystals for Enhanced Chemical Gas Sensors at Room Temperature

IntroductionA low-cost chemical sensor for ammonia (NH3) detection is highly demanded nowadays for several important applications. Two-dimensional (2D) nanomaterials such as graphene/reduced graphene oxide (rGO), transitional metal dicharcogenides, black phosphor and transition metal carbonitride (MXene) have found a promising application in the fields of gas sensing electronics at room temperature due to their unique microstructure, electrical properties and excellent gas adsorptions ability. Decoration of the secondary phase such as noble metals and metal oxide nanocrystals to form heterojunctions with two-dimensional materials can effectively improve the inadequacy of two-dimensional materials based gas sensors. It takes advantages of the difference in the Fermi level of each phase to make the electrons transfer from one material to the other and thus enriching the electron concentration on the surface of one material that is dominant in the electrical transport. In this way, more ionized oxygen is chemisorbed, leading to the improvement of the gas sensing properties [1].In this work, 2D MXene heterojunctions incorporated with SnO2 nanoparticles have been synthesized by using hydrothermal method. The as-fabricated MXene/SnO2 heterojunction based chemiresistive-type sensor showed excellent sensitivity to different concentrations of ammonia from 0.5-100 ppm at room temperature. The response has about 20 times higher than those reported in literature to 100 ppm NH3 and an excellent selectivity.Preparation and characterizations The Ti3AlC2 was purchased directly from Beijing Forsman Corp. The concentrated hydrochloric acid (HCl) was diluted to 9 M. 2 g of lithium fluoride (LiF) was added into 20 ml diluted hydrochloric acid and stirred with magnetic mixer. 2 g Ti3AlC2 was slowly and evenly dispersed in the solution over a period of several minutes and subsequently stirred at 35 ℃ for 48 h to obtain the MXene. 70 mg of MXene powder was dispersed in 30 ml of deionized water after grinding and sonicated for 30 min. 73.5 mg of stannic chloride pentahydrate (SnCl4·5H2O) was added into the suspension and stirred with magnetic stirrer at room temperature. The suspension was then loaded in a 50 ml Teflon-lined autoclave. The autoclave was sealed and heated in an KSL-1200X hydrothermal system at 180 ℃ for 12 h to obtain the MXene-SnO2 hybirds. The samples were then characterized by XRD, SEM, XPS, Raman and TEM-ED. The MXene/SnO2 based chemirestive-type sensor was measured by a static volumetric method. The resistance of the sensor is directly measured by a digital multimeter (Agilent 34410A). The responses of the sensors were defined as the relative change in the resistances of the sensors in the air and those in the tested gas. Results and Conclusions Fig.1a shows the XRD of the prepared samples. Appearance and down-shift of the peak at ~10 oC indicates the successful achievements of MXene and thus the MXene-SnO2 composite heterojunctions [2-3].Fig.1 (b-c) show the micrographs of the surface morphology of the MXene and heterojunctions. The etched MXene material has obvious layered structure with sizes ranging from 2 μm to 4 μm. The thickness of MXene is about 75 nm indicating the sample contains about 100 single layers of MXene. The granular SnO2 nanoparticles are intimately attached to the surface of MXene. Fig.2 (b) shows the Raman spectra of MXene and Mxene/SnO2 heterojunction. The appearance of both D-band and G-band in the MXene/SnO2 heterojunction sample indicated that MXene remained well during the hydrothermal reaction. Fig.2(c) shows the Ti core level (2p) spectra of the MXene and MXene/SnO2. Ti - X corresponds to titanium carbide or titanium oxynitride. Fig.2d indicates that the peaks at 530.1 and 532 eV correspond to oxygen vacancies and O=C-OH, respectively, suggesting that these and surface-adsorbed oxygen tend to form more active sites, thereby enhancing sensing capability.The sensors using MXene/SnO2 heterojuction shows excellent response and selectivity to low-level NH3 from 0.5-9 ppm at RT (Fig.3). Since the work function of MXene (3.4 eV) was slightly lower than that of SnO2 (4.7 eV), Schottky-type junctions were formed across MXene/SnO2 interfaces (Fig.4). Electrons would transfer from SnO2 to MXene, and the depletion layer was deepened on the surface of MXene. MXene could then chemically adsorb more oxygen, and the response of the MXene/SnO2 heterojunction was thus significantly enhanced.

Sn4P3-inlaid graphene oxide nanohybrid through low-temperature solid state reactions toward high-performance anode for sodium-ion batteries

Due to nature abundant and low-cost of sodium reserves with broad distribution in the earth's crust, sodium-ion batteries (SIBs) have attracted widespread attention for their great potential application in low-speed electric vehicles and large-scale energy storage system. However, their practical application is still hampered by the lack of decent anode materials. In this work, we develop an effective strategy to fabricate a nanohybrid of Sn4P3 and graphene oxide and demonstrate its outstanding sodium-storage behavior as an anode material for SIBs. By directly grinding tin(IV) chloride pentahydrate, sodium hydroxide, graphene oxide (GO) and surfactant PEG-200 at ambient temperature, an effective solid state reaction occurred to give rise to a precursor (named as SnO2/GO-PEG200), i.e. a nanocomposite of SnO2 encapsulated within GO matrix. After subsequent phosphorization at 280 °C using sodium hypophosphite monohydrate as phosphorous source, a nanohybrid of Sn4P3 and graphene oxide (designated as Sn4P3/GO-PEG200) was acquired. The coexistence of Sn4P3 nanoparticles and GO nanosheets endows the nanohybrid with improved electronic conductivity, highly structural integrity and superior electrochemical performance. When employed as anode material for SIBs, the nanohybrid anode demonstrates a good cycling stability (419 mA h g−1 after 100 cycles at 0.1 A g−1), with a remarkable rate capabilities (325 mA h g−1 at a current density of 1 A g−1 and 187 mA h g−1 at a current density of 5 A g−1, respectively).

Dysprosium stannate (Dy2Sn2O7)-nanostructured thin films prepared by spray pyrolysis technique: effect of dysprosium and annealing on the physical properties

In this paper, dysprosium stannate-nanostructured thin films (Dy2Sn2O7) were deposited by spray pyrolysis method on fused silica substrates at T = 480 °C. A solution of 0.1 molar tin(IV) chloride pentahydrate (SnCl4⋅5H2O) and dysprosium(III) nitrate with mole ratios of [Dy/Sn] % = 10, 30, 50, 70, and 100% was used to prepare dysprosium stannate-nanostructured thin films (Dy2Sn2O7) by spray pyrolysis method. Then, the effect of Dy-content and annealing temperature in air at T = 500, 600, 1100 and 1200 °C, on structural conversion and optical properties were investigated for these films. The X-ray diffraction (XRD) patterns indicated that the dominant phase above T = 1100 °C is pyrochlore phase of dysprosium stannate. The field emission scanning electron microscopy (FE-SEM) images showed the formation of nanocrystals of dysprosium stannate with pyrochlore structure. The FE-SEM images show that the surface morphologies of as-prepared films are in the form of cubic nanocrystals before annealing and nano-polyhedral as agglomerated after annealing at T = 1200 °C. The results of UV–Vis analysis indicated that with increasing the Dy-content and annealing at T = 1200 °C, optical transmittance and bandgap was increased. The optical bandgap for ratios of [Dy/Sn] = 50 and 100% were obtained 2.65 and 2.76 eV, respectively, after annealing at T = 1200 °C.

Film Growth of Tetragonal SnO2 on Glass Substrate by Dip-Coating Technique for Ethanol Sensing Applications

A thin film sensor based on tetragonal SnO2 nanoparticles was fabricated by combining the sol–gel method and a dip-coating technique on a cylindrical glass substrate. The sensing material was produced through a cycling annealing process at 400 and 600 °C, using tin chloride (IV) pentahydrate as a precursor in polyethylene glycol (PEG) solution as a surfactant. Materials were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), revealing tetragonal phase formation with no impurities. The sensor′s assembly was done with low-cost materials such as Cu electrodes, Cu-Ni tube pins, and glass-reinforced epoxy laminate as the base material. For signal variation, an adequate voltage divider circuit was used to detect ethanol′s presence on the surface of the sensor. The fabricated sensor response to gaseous ethanol at its operating temperature at ambient pressure is comparable to that of a commercial sensor, with the advantage of detecting ethanol at lower temperatures. The sensor response (S = Ra/Rg) to 40 ppm of ethanol at 120 °C was 7.21. A reported mathematical model was used to fit the data with good results.

Biosynthesis of SnO2 nanoparticles by aqueous leaves extract of Aquilaria malaccensis (agarwood)

Biosynthesis of tin oxide nanoparticles (SnO2 NPs) was cost-effectively carried out in non-toxic aqueous mixture of Aquilaria malaccensis (agarwood) leaves extract and tin (IV) chloride pentahydrate solution at room temperature. The synthesized SnO2 NPs were characterized by using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDX) and UV-visible diffuse reflectance spectroscopy (DRS). The results from FT-IR spectra of A. malaccensis leaves shows the presence of functional groups of polyphenolic from bioactive compounds which act as the template for reducing and capping agents during the synthesis activity. The structural properties of the obtained nanoparticles are studied using X-ray diffraction, which indicates that the crystallite size are 6.3 and 3.4 nm for sample synthesized from extract of fresh and old leaves respectively. The morphology of the nanoparticles shows uniform distribution of agglomerated spherical nanoparticles. DRS absorption spectrum indicates the band-gap for both samples 3.23 and 3.35 eV respectively. The green synthesized SnO2 NPs is suggested may play forthcoming significant roles in catalysis and optoelectronic devices.

Impact of morphology evolution of ZnSn(OH)6 microcubes on photocatalytic activity of ZnSn(OH)6/SnO2/rGO ternary nanocomposites for efficient degradation of organic pollutants

Abstract In this study, Zinc hydroxystannate/tin dioxide/reduced graphene oxide (ZnSn(OH)6/SnO2/rGO) ternary nanocomposites were synthesized via a facile one-step hydrothermal route by using graphene oxide, zinc nitrate hexahydrate, and tin (IV) chloride pentahydrate as the precursors. The crystal structure, morphology, and optical properties of ZnSn(OH)6/SnO2/rGO ternary nanocomposites were characterized by x-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Raman spectroscopy and UV–vis spectroscopy, respectively. The results of XRD pattern revealed the formation of fcc perovskite ZnSn(OH)6 (ZHS) and tetragonal SnO2 structure. The FESEM images displayed that the ZHS microcubes and SnO2 nanoparticles were distributed on the graphene sheets. The composites were used as photocatalyst for degradation of methylene blue (MB) molecules. The photocatalytic performance of the samples showed that the ZHS/SnO2/rGO nanocomposite exhibited a much higher photocatalytic activity than pure samples. The ternary nanocomposite synthesized at 160 °C with a graphene oxide concentration of 1 mg/mL has the ability to completely degradation MB in less than 60 min under UV radiation. The rate of hydroxyl radical (·OH) generated in the photocatalytic process was investigated using PL spectroscopy and coumarin (COU) as a probe molecule. Thus it can be intended that the mechanism of MB degradation by the as-synthesized nanocomposites followed indirect oxidation of the dye by ·OH generated during the photocatalyst process.

Synthesis of hybrid amorphous/crystalline SnO2 1D nanostructures: investigation of morphology, structure and optical properties

The aim of the study was to prepare SnO2 nanowires via a combination of electrospinning and the sol–gel method from a polyvinylpyrrolidone (PVP)/dimetylformamide (DMF)/ethanol(EtOH)/tin(IV) chloride pentahydrate (SnCl4·5H2O) solution. The morphology, structure and chemical composition of the obtained PVP/SnO2 nanofibers and SnO2 nanowires were examined using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) as well as a scanning electron microscope (SEM) with an energy dispersive spectrometer (EDX). The optical property analysis was performed on the basis of UV–Vis spectra of absorbance as a function of the wavelength, based on which the rated values of band gaps of the fabricated 1D nanostructures were determined. The morphology analysis showed that the obtained amorphous SnO2 nanowires with crystalline protuberances were characterized by a diameter of 50 to 120 nm. Results demonstrated that nanowires with a ratio of 1:1 precursor to polymer in the spinning solution were characterized by the smallest diameter after calcination and the smallest energy gap of 3.3 eV among all investigated samples. The rest of the studied materials were characterized by a larger energy gap (3.8 and 3.9 eV).

Effect of gadolinium on tin oxide thin films prepared by nebulizer spray pyrolysis method

Gadolinium-doped tin oxide (SnO2: Gd) thin films were prepared by the nebulizer spray pyrolysis technique on glass substrates using tin (IV) chloride pentahydrate (SnCl2·5H2O) and Gadolinium Sulphate Octahydrate as source materials. Different wt % of doping such as (0%, 1%, 2% and 3%) Gadolinium was used to prepare the spray solution, and their effects on structural, morphological, optical, properties were investigated. X-ray diffraction patterns revealed the polycrystalline tetragonal structure of prepared films. The crystallite size value varies due to Gd doing level. SEM images demonstrated well-aligned tetragonal-shaped nano-grains. Optical band gap values were estimated to be in the range of 3.78–3.82 ​eV by Tauc’s plot. The effects of Gd doping level on the SnO2 thin films obtained using an excitation wavelength of 350 ​nm exhibit emission peaks centered at 361 ​nm, 496 ​nm, 520 ​nm, 540 ​nm and 594 ​nm respectively. It’s indicated that SnO2 thin films exhibited a broad dominant peak near 396 ​nm (about 3.14 ​eV). Raman spectroscopy indicates the spectra for as deposited SnO2 is dominated by presence of strong and sharp peak at 2434 ​cm−1 along with the peak of smaller intensity at 482 ​cm−1.

Facile and rapid synthesis of tetrakis-2-amino-5-methylpyridinecopper(II) chloride pentahydrate

Pyridine and its derivatives are important compounds with tremendous applications. Pyridine derivatives, such as aminopyridine, have been widely investigated concerning their biological activity. It is reported that generally biological activities of the compound increased after complexation. Tetrakis-2-amino-5-methylpyridinecopper(II) chloride pentahydrate has been synthesized facilely in less than five minutes. It was formed by mixing CuCl2-2H2O and 2-amino-5-methylpyridine in 1:4 mole ratio in ethanol at room temperature. The complex was characterized to determine its proposed empirical formula and the structure. The forming of the complex was indicated by shifting of maximum wavelength (Amax) of UV-Vis spectra towards smaller than CuCl2-2H2O from 850 nm to 675 nm. Atomic Absorption Spectroscopy (AAS) measurement showed the content of copper to be 9.63 % corresponding to the theoretical value of copper content in Cu(2-amino-5-methylpyridine)4Cl2(H2O)x (x= 4, 5, or 6). Thermogravimetric Analysis and Differential Scanning Calorimetry (TGA-DSC) showed a mass reduction of 13.02 % which was equivalent to the evaporation of five molecules of lattice water. The cation and anion charge ratio of the complex was 2:1. This four coordinated-complex was paramagnetic with an effective magnetic moment of 1.83 BM. The proposed empirical formula of the complex was [Cu(2-amino-5-methylpyridine)4]Cl2-5H2O.