Monobutyltin Trichloride Research Articles

An Aerosol-Assisted Chemical Vapor Deposition Route to Tin-Doped Gallium Oxide Thin Films with Optoelectronic Properties.

Gallium oxide is a wide-bandgap compound semiconductor material renowned for its diverse applications spanning gas sensors, liquid crystal displays, transparent electrodes, and ultraviolet detectors. This paper details the aerosol assisted chemical vapor deposition synthesis of tin doped gallium oxide thin films using gallium acetylacetonate and monobutyltin trichloride dissolved in methanol. It was observed that Sn doping resulted in a reduction in the transmittance of Ga2O3 films within the visible spectrum, while preserving the wide bandgap characteristics of 4.8 eV. Furthermore, Hall effect testing revealed a substantial decrease in the resistivity of Sn-doped Ga2O3 films, reducing it from 4.2 × 106 Ω cm to 2 × 105 Ω cm for the 2.5 at. % Sn:Ga2O3 compared to the nominally undoped Ga2O3.

Self-assembly of broadband-emitting SnOx nanodots for efficient Cr(VI) detection

Chromium is a metal commonly used in the manufacturing industry. However, when present in industrial wastewater and refuse, chromium causes serious water pollution. In this study, we synthesized a high-efficiency low-cost SnOx (SnO/SnO2) nanodot (ND) photocatalyst using monobutyltin trichloride (MBTC) using a one-step thermal decomposition process. SnOx NDs not only exhibit strong broadband and multicolor fluorescence emission (λem ranging from 450 nm to 585 nm), but also emit white light under ultraviolet irradiation. We also found that, under visible-light irradiation, SnOx NDs exhibited a photocurrent response that improved photocatalytic activity. In addition, we used electrochemical impedance spectroscopy (EIS) to detect Cr(VI) over a concentration range of 5–1000 ppb, with a detection limit of 0.006 ppb under light. This detection limit is lower than the maximum limit of 50 ppb for human water consumption, as stipulated by the European Union.

Low temperature open-air plasma deposition of amorphous tin oxide for perovskite solar cells

A low-temperature, open-air plasma process to deposit amorphous SnOx thin films as an electron-transport layer in a planar-heterojunction n−i−p perovskite solar cell is reported. Open-air plasma processing is a scalable, low capital expenditure technique capable of manufacturing-scale production without enclosures or vacuum pumps. The technique provides flexibility to tune SnOx film composition and properties by adjusting several easily accessible processing parameters. In this study, we demonstrate large area SnOx thin film deposition on substrates up to 100 cm2. The SnOx films are deposited using monobutyltin trichloride as the chemical precursor and formed without any post-annealing, which has the potential for lowering costs as an in-line process. The film exhibits low surface roughness, excellent optical transmission of greater than 90 % across the visible regime, and low electrical resistivity of 13.3 Ω*m, which is multiple orders of magnitude lower than previously reported values of amorphous SnO2 thin films. The film is then incorporated into a planar perovskite solar cell with a power conversion efficiency of 11.8 %. These factors suggest that open-air plasma-deposited SnOx thin films can potentially be compatible with low-cost and large-scale fabrication of organohalide lead perovskite solar cells and modules.

Effect of hydrogen peroxide on photoelectric properties of high-transmittance FTO films prepared by spray pyrolysis

The FTO film prepared by spray pyrolysis has low efficiency and most of the precursors are discharged in the form of waste steam. According to the high oxidation property of H2O2, it is attempted to improve the film formation rate by changing the concentration of H2O2. Fluorine-doped SnO2 (FTO) thin films with high transmittance were prepared by spray pyrolysis using monobutyltin trichloride as the tin source and ammonium fluoride as the fluorine source. Different concentrations of hydrogen peroxide (0–0.08 M) are added to the precursor solution. In this paper, we studied the effect of hydrogen peroxide on the structure, surface morphology and photoelectric properties of FTO thin films. The results show that the growth rate of the FTO films increased from 6.04 nm/s to 8.36 nm/s with the increase of H2O2 concentration from 0 to 0.08 M. The optimum preparation process is H2O2 concentration controlled at 0.04 M, and FTO thin films suitable for solar cells are prepared. It has excellent performance parameters; carrier concentration:2.74 ∗ 1021 cm−3; carrier mobility:55.92 cm2 V−1 s−1; photoelectric quality factor:2.66 × 10−3·Ω−1and the average transmittance of visible light: 79.87%. At the same time, increasing H2O2 concentration leads to narrowing of optical band gap. Adding appropriate hydrogen peroxide concentration can improve the film production rate and obtain excellent quality films.

Effect of F and Nb co-doping on structural, electrical and optical properties of spray deposited tin oxide thin films

F and Nb co-doped tin oxide films were deposited from monobutyltin trichloride (C4H9SnCl3) on glass substrates at 470 °C by spray pyrolysis. The evolution of the film structure and morphology was investigated by X-ray diffraction and scanning electron microscopy, respectively. All the films were a single phase with polycrystalline, exhibiting a tetragonal cassiterite structure with (200) orientation. The introduction of F and Nb contributed to the growth of the films towards (200) crystal orientation and the formation of pyramidal shape particles with (101) twin planes. Resistivity, carrier concentration, and Hall mobility values of 3.62 × 10−4 Ω cm, 7.463 × 1020 cm−3, and 27.8 cm2 V−1 s−1, respectively, were achieved in the films for a dopant concentration of 20 at.% F and 1 at.% Nb in the precursor solution. Also, the transmittance of all the films in the visible range reached about 80% and the infrared reflectivity was oscillated between 92 and 96%.

Biotransformation of tributyltin chloride to less toxic dibutyltin dichloride and monobutyltin trichloride by Klebsiella pneumoniae strain SD9

A tributyltin chloride (TBTCl) resistant bacterial strain was isolated from the Zuari estuary, in Goa, India, and identified as Klebsiella pneumoniae based on biochemical characteristics and 16S rRNA sequence analysis, and designated as strain SD9. It could utilize TBTCl as a sole carbon source in mineral salt medium and tolerated up to 2.5 mM TBTCl with maximum growth at 2 mM. Nuclear magnetic resonance spectroscopic analysis of column purified TBTCl degradation products clearly demonstrated the presence of dibutyltin dichloride (DBTCl2) and monobutyltin trichloride (MBTCl3). Mass spectrometry further confirmed degradation of toxic TBTCl into its less toxic derivatives, viz., DBTCl2 and MBTCl3. This strain also showed enhanced siderophore production in the presence of TBTCl, which was demonstrated by chrome azurol S agar assay as an increase in diameter of the orange halo around the bacterial colony in the presence of 2 mM TBTCl; this seems to be a mechanism to counteract TBTCl toxicity. Furthermore, scanning electron microscopy revealed significant morphological alterations as shrinkage in cell size along with roughness of cell surface when bacterial cells were exposed to 2 mM TBTCl. These interesting characteristics of this estuarine bacterium make it a potential tool for bioremediation of TBTCl-contaminated sites since it possesses biotransformation capability to convert TBTCl into DBTCl2 and MBTCl3.

Evaluation of an alternative in vitro test battery for detecting reproductive toxicants in a grouping context.

Previously we showed a battery consisting of CALUX transcriptional activation assays, the ReProGlo assay, and the embryonic stem cell test, and zebrafish embryotoxicity assay as 'apical' tests to correctly predict developmental toxicity for 11 out of 12 compounds, and to explain the one false negative [7]. Here we report on applying this battery within the context of grouping and read across, put forward as a potential tool to fill data gaps and avoid animal testing, to distinguish in vivo non- or weak developmental toxicants from potent developmental toxicants within groups of structural analogs. The battery correctly distinguished 2-methylhexanoic acid, monomethyl phthalate, and monobutyltin trichloride as non- or weak developmental toxicants from structurally related developmental toxicants valproic acid, mono-ethylhexyl phthalate, and tributyltin chloride, respectively, and, therefore, holds promise as a biological verification model in grouping and read across approaches. The relevance of toxicokinetic information is indicated.

Transmission electron microscopy on early-stage tin oxide film morphology grown by atmospheric pressure chemical vapor deposition

Nucleation and morphology development during the early stages of chemical vapor deposition (CVD) processes are believed to be of major importance for the overall film properties. Here, the authors have investigated the nucleation of tin oxide films, comparing different tin precursors (tin tetrachloride (TTC) and monobutyl tin trichloride (MBTC)) and focusing on the effect of methanol addition on the film morphology. Employing electron transparent silicon oxide membranes as substrates and combining transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analysis on the same set of samples, we describe a detailed picture of nucleation behavior and film growth during early stages of film formation. Our main conclusion is that methanol addition during deposition acts as surfactant, lowering the surface energy of the substrate and resulting in a higher nucleation grain density. Based on these results, we propose a film growth model based on surface energy to explain morphology differences in tin oxide films resulting from methanol addition. cop. 2014 Elsevier B.V.

Tailoring of textured transparent conductive SnO2:F thin films

In order to optimize the light trapping, textured SnO2:F (FTO) films have been successfully deposited and optimized on glass in large scale using atmospheric pressure chemical vapor deposition (APCVD) method on an industrial production line. The microstructures, optical and electrical properties of the films were investigated as a function of the total flow rate and fluorine doping concentration. The as-deposited FTO polycrystalline films possessed the tetragonal rutile structure of SnO2. Enhanced light trapping has been achieved with the increased surface roughness of the films by manipulating the total flow rate of monobutyltin trichloride (MBTC) and trifluoro acetic acid (TFA), while the corresponding high transmittance and conductivity remained stable. The optimized film with haze value of 10.9%, a figure of merit at the level of∼10−3 and sheet resistance of∼11Ωsq−1, showed good potential to improve the efficiency of silicon thin film solar cells.

High-performance tandem silicon solar cells on F:SnO2

High-performance transparent conducting oxides (TCOs) have significance for optimising PV performance. The efficiency of the resulting solar cells is dependent particularly on achieving high light scattering, low resistivity and low absorption (via low free carrier absorption), in addition to suitable surface morphology for absorber growth quality. These properties have been targeted by systematic exploration of the Atmospheric Pressure Chemical Vapour Deposition (APCVD) growth parameters, in particularly the effect of the tin precursor to water ratio.Using the APCVD process F-doped SnO2 has been deposited on glass using monobutyl tin trichloride with trifluoro-acetic acid as the dopant source. Experiments established that an increased water to tin precursor ratio gave smaller surface features, along with increased electrical mobility and optical transmittance at high reactant ratios. Samples were then used in manufacture of thin film solar cells, which showed enhanced performance, in comparison to commercially available TCO CVD coated glasses, with high quantum efficiency yield. In particular, high water to tin precursor ratios led to much improved open circuit voltages, fill factors and high current densities within the cells. Tandem cells with efficiencies of 10.75% were achieved, which were higher than those produced concurrently using commercially available TCO both on-line 9.50% and off-line 10.20%.

The Influence of F-Doping in SnO2 Thin Films

Transparent conductive oxide (TCO) films are widely used in many consumer products. The properties of the TCO can critically affect the efficiency of the application. With this in mind the surface morphological, optical and electrical properties have been targeted by systematic exploration of the Atmospheric Pressure Chemical Vapour Deposition (APCVD) growth parameters and in this work particularly the effect of dopant concentrations. APCVD processes are particularly suited to use in industry due to the high volume, continuous growth processes and fast growth rates achievable. Using the APCVD process, F-doped SnO2 has been deposited on glass using monobutyl tin trichloride with trifluoro-acetic acid as the dopant source. The deposited films were characterised for crystallinity, morphology, optical haze and electrical properties. Additionally, the stability of the films to post growth annealing were studied, as this is an important factor as most TCO’s will need further processing for the production of consumer products. It has been shown that increasing the dopant levels led to a decrease in surface roughness along with a reduction in feature size. The surface features also showed a decrease in the average angle, although with a broader distribution. As expected increased doping gave increased carrier concentration and mobility, with a non-linear decrease in resistivity. The polycrystalline structure became less selective in orientation on doping, but no further change was seen on increasing the dopant level. The samples tested showed only marginal changes in electrical and optical properties at elevated temperatures, confirming their thermal stability.

The development of high performance SnO2:F as TCOs for thin film silicon solar cells

High performance transparent conducting oxides (TCOs) have significance for optimising photovoltaic (PV) performance. The efficiency of the resulting solar cells is dependent particularly on achieving high light scattering, low resistivity and low absorption (via low FCA). These properties have been targeted by systematic exploration of the atmospheric pressure chemical vapour deposition growth parameters, in particularly the deposition temperature and growth rate.APCVD processes are particularly suited to use in industry due to the high volume, continuous growth processes and fast growth rates achievable. Using the APCVD process, F-doped SnO2 has been deposited on glass using monobutyl tin trichloride with trifluoro-acetic acid as the dopant source. The deposited films were characterised for crystallinity, morphology (roughness), optical haze and electrical properties (via Hall measurement) to aid optimisation of material suitable for solar cells.Samples were then used in manufacture of single a-Si:H solar cells, which showed enhanced performance, in comparison to commercially available TCO CVD coated glasses, with high quantum efficiency yield.

Simultaneous Determination of Organotin Compounds in White Wine by Gas Chromatography-Mass Spectrometry

A simple, reliable, and effective analytical method was developed for the simultaneous determination of five organotin compounds (OTCs) including monobutyltin trichloride dibutyltin dichloride tributyltin chloride tetrabutyltin and triphenyltin chloride in white wines. The OTCs were derivatized with sodium tetraethylborate (NaBEt4), and their derivatives were extracted by liquid-liquid extraction (LLE) into n-hexane. The experimental variables, such as type and volume of extraction solvents, amount of derivatization reagent NaBEt4 and extraction time were optimized. The determination of ethylated derivatives of OTCs in the final extracts was carried out by gas chromatography-mass spectrometry (GC-MS). Under optimized conditions, good linearity was observed when analytical concentrations were in the range of 0.01–4.0 µg · mL−1, the linearity correlation coefficients were between 0.9982 and 0.9987, with the LODs in the range of 0.2–3.0 µg · L−1, and the LOQs varied from 0.6 to 10.0 µg · L−1. The obtained recoveries were in the range of 78.0–120.0%, with the relative standard deviations equal to or lower than 8.1%. This method was applied to the determination of OTCs in white wines with satisfactory results.

Textured Fluorine‐Doped Tin Dioxide Films formed by Chemical Vapour Deposition

The use of an aerosol delivery system enabled fluorine-doped tin dioxide films to be formed from monobutyltin trichloride methanolic solutions at 350-550 °C with enhanced functional properties compared with commercial standards. It was noted that small aerosol droplets (0.3 μm) gave films with better figures of merit than larger aerosol droplets (45 μm) or use of a similar precursor set using atmospheric pressure chemical vapour deposition (CVD) conditions. Control over the surface texturing and physical properties of the thin films were investigated by variation in the deposition temperature and dopant concentration. Optimum deposition conditions for low-emissivity coatings were found to be at a substrate temperature of about 450 °C with a dopant concentration of 1.6 atm% (30 mol% F:Sn in solution), which resulted in films with a low visible light haze value (1.74%), a high charge-carrier mobility (25 cm(2) V s(-1)) and a high charge-carrier density (5.7×10(20) cm(-3)) resulting in a high transmittance across the visible (≈80%), a high reflectance in the IR (80% at 2500 nm) and plasma-edge onset at 1400 nm. Optimum deposition conditions for coatings with applications as top electrodes in thin film photovoltaics were found to be a substrate temperature of about 500 °C with a dopant concentration of 2.2 atm% (30 mol% F:Sn in solution), which resulted in films with a low sheet resistance (3 Ω sq(-1)), high charge-carrier density (6.4×10(20) cm(-3)), a plasma edge onset of 1440 nm and the films also showed pyramidal surface texturing on the micrometer scale which corresponded to a high visible light haze value (8%) for light scattering and trapping within thin film photovoltaic devices.

Deposition of indium tin oxide by atmospheric pressure chemical vapour deposition

We report the deposition of indium tin oxide (ITO) by atmospheric pressure chemical vapour deposition (APCVD). This process is potentially scalable for high throughput, large area production. We utilised a previously unreported precursor combination; dimethylindium acetylacetonate, [Me2In(acac)] and monobutyltintrichloride, MBTC.[Me2In(acac)] is a volatile solid. It is more stable and easier to handle than traditional indium oxide precursors such as pyrophoric trialkylindium compounds. Monobutyltintrichloride (MBTC) is also easily handled and can be readily vaporised. It is compatible with the process conditions required for using [Me2In(acac)].Cubic ITO was deposited at a substrate temperature of 550°C with growth rates exceeding 15nm/s and growth efficiencies of between 20 and 30%. Resistivity was 3.5×10−4Ωcm and transmission for a 200nm film was >85% with less than 2% haze.

Speciation of organotin compounds in environmental samples with semi-permanent coated capillaries by capillary electrophoresis coupled with inductively coupled plasma mass spectrometry

A novel method using capillary electrophoresis (CE) coupled with inductively coupled plasma mass spectrometry (ICP-MS) for the separation of four organotin compounds has been developed. Semi-permanent coating of dioctadecyl dimethyl ammonium chloride (DDAC) was applied and investigated to enhance separation efficiency of trimethyltin (TMT) chloride, tributyltin (TBT) chloride, dibutyltin (DBT) dichloride and monobutyltin (MBT) trichloride. The electrolyte composition and ionic strength were optimized. Running buffer containing 0.608 mol L−1 HAc and 7 mmol L−1 NaAc was selected for the separation. The detection limits of the four organotin compounds ranged from 0.037 to 0.112 mg L−1 (as Sn) and the values of the relative standard deviation (RSD) were below 3.1% for migration time, less than 7.8% for peak height and not more than 8.4% for peak area. The developed method was successfully applied for speciation analysis of four organotin compounds in one certified reference material (CRM 477, mussel tissue), and environmental samples including water samples, grape wine and biological samples (Mya arenaria Linnaeus). The determined values (as organotin compounds) of CRM 477 (1.81 ± 0.13 (TBT), 1.36 ± 0.16 (DBT), 1.17 ± 0.18 (MBT)) were in good agreement with the certified values (2.20 ± 0.19 (TBT), 1.54 ± 0.12 (DBT), 1.50 ± 0.28 (MBT)). 0.325 mg L−1 MBT and 1.02 μg g−1 (as Sn) TBT were found in grape wine and Mya arenaria Linnaeus samples.

Optimization of Solar Cell Performance using Atmospheric Pressure Chemical Vapour Deposition deposited TCOs

Photovoltaic cell performance can be greatly improved by optimising the transparent conducting oxide used as the front contact. We have developed an advanced atmospheric pressure chemical vapour deposition (APCVD) process, by applying fast experimentation and using a combinatorial chemistry approach to aid the studies. By use of this process, F-doped SnO2 has been deposited using either monobutyl tin trichloride or tin tetrachloride with aqueous HF or trifluoro-acetic acid as the dopant source. The deposited films were characterised for crystallinity, morphology, resistivity and growth rate to aid optimisation of material suitable for solar cells. The results from use of the different tin precursors and dopants were compared. The most striking changes were related to resistivity and surface morphology. Compared with commercially available TCO CVD coated glasses, our coatings show excellent performance resulting in a high quantum efficiency yield for a-Si:H solar cells.

Influences of H2O on the Structure and Properties of Sn:F Film

Abstract F-doped tin oxide (Sn:F) film was prepared by atmosphere pressure chemical vapor deposition (APCVD) on float glass using monobutyltin trichloride (C 4 H 9 SnCl 3 , MBTC) and trifluoro acetic acid (CF 3 COOH, TFA) as the precursor and dopant, respectively. H 2 O with different concentrations was used as the activator. The prepared films were characterized by means of XRD, SEM, and UV-VIS-NIR spectroscopy. Experimental results reveal that the structures and properties of the films are greatly affected by the H 2 O content. H 2 O in a certain range of concentrations will promote the formation of Sn:F film and improve the properties of the films.

An Organotin Mixture Found in Polyvinyl Chloride (PVC) Pipe is not Immunotoxic to Adult Sprague-Dawley Rats

Organotin compounds used in polyvinyl chloride (PVC) pipe production are of concern to the U.S. Environmental Protection Agency (EPA) because they leach from supply pipes into drinking water and are reported multisystem toxicants. Immune function was assessed in male Sprague-Dawley rats exposed to the mixture of organotins used in PVC pipe production. Although several of these organotins are reported immunotoxicants, their immunotoxicity as a mixture when given by drinking water has not been evaluated. Adult male rats were given drinking water for 28 d containing a mixture of dibutyltin dichloride (DBTC), dimethyltin dichloride (DMTC), monobutyltin trichloride (MBT), and monomethyltin trichloride (MMT) in a 2:2:1:1 ratio, respectively, at 3 different concentrations (5:5:2.5:2.5, 10:10:5:5, or 20:20:10:10 mg organotin/L), MMT alone (20 or 40 mg MMT/L), or plain water as a control. Delayed-type hypersensitivity, antibody synthesis, and natural killer cell cytotoxicity were evaluated in separate endpoint groups (n = 8/dose; 24/endpoint) immediately after exposure ended. The evaluated immune functions were not affected by the mixture or by MMT alone. Our data suggest that immunotoxicity is unlikely to result from the concentration of organotins present in drinking water delivered via PVC pipes, as the concentrations used were several orders of magnitude higher than those expected to leach from PVC pipes.

Atmospheric plasma discharge chemical vapor deposition of SnO x thin films using various tin precursors

A series of 0.2–0.6 μm thick SnO x films were deposited onto borosilicate and sodalime silica glass substrates by atmospheric plasma discharge chemical vapor deposition at 80 °C. SnO x films deposited from monobutyltin trichloride contained a large percentage of SnCl 2:2H 2O, and therefore were partially soluble in water. SnO x coatings deposited from tetrabutyltin were not soluble in water or organic solvents, had good adhesion even at growth rates as high as 2.3 nm/s, had high transparency of ∼ 90% and electrical resistivity of 10 7 Ω cm. As-grown tin oxide coatings were amorphous with a small concentration of SnO 2, SnO and Sn crystalline phases as determined by grazing angle X-ray diffraction and X-ray photoelectron spectroscopy measurements. Upon annealing in air at 600 °C the resistivity of SnO x films decreased to 5–7 Ω cm. Furthermore, optical and X-ray measurements indicated that SnO x was converted into SnO 2 (cassiterite) with a direct band gap of 3.66 eV. Annealing of as-grown SnO x films in vacuum at 340 °C led to formation of the p-type conductor SnO/SnO x . The indirect band gap of SnO was calculated from the optical spectra to be 0.3 eV.