Colloidal Tin Research Articles

Wireless flexi-sensor using narrow band quasi colloidal 3D tin telluride (SnTe) for respiratory, environment, and proximity sensing

We developed a wireless and flexible humidity sensor based on three-dimensional (3D) narrow band quasi colloidal (NBQC) tin telluride (SnTe) material. Pristine SnTe granules were exfoliated into a homogeneous quasi colloidal (HQC) solution through mechanical liquid phase exfoliation (MLPE). Resulting HQC solution had a higher surface area with randomly shaped 3D NBQC SnTe particles that increased its humidity sensing ability by rendering more active sites and irregular pathways for interaction with water molecules. Fabrication of SnTe humidity sensor included highly conductive (2.5 μΩ/cm) and precise plasma sputtered gold (Au) inter-digital electrodes (IDEs) using a shadow mask on the flexible substrate followed by coating the thin film of 3D HQC SnTe. The SnTe humidity sensor showed variance in both capacitance and impedance with changing relative humidity (%RH). Impedance response of SnTe humidity sensor was more sensitive compared to its capacitance. We adjusted the operating frequency of our humidity sensor (1, 10, and 100 kHz) to maximize sensitivity, enhance accuracy, and reduce interference. The developed humidity sensor exhibited efficient performance, including a wide operating range (5–92 %RH), high sensitivity (85.6 kΩ/%RH), consistent stability (>48 days), and a fast response/recovery time (1.7/3.2 s). The narrow band gap of SnTe enabled strong interaction with water molecules, leading to a highly sensitive impedance response to %RH. To improve its mobility, portability, and measurability, the SnTe humidity sensor was made wireless for easy integration into a variety of devices. Our 3D NBQC SnTe humidity sensor showed its potential applications in environment monitoring, health monitoring, and proximity sensing.

Regulating Lewis Acid‐Base Interactions to Enhance Stability of Tin Oxide for High‐Performance Perovskite Solar Cells

AbstractPerovskite solar cells are an attractive technology for renewable energy production. However, stability issues with the electron transport layer (ETL), particularly the colloidal tin oxide (SnO2) solution, can impact cell efficiency. In this study, a novel acidization treatment is introduced to reactivate long‐time stored SnO2 solutions, which previously led to low‐efficiency perovskite solar cells. The acidization treatment results in enhanced conductivity of the SnO2 layer, improved perovskite film quality, and ultimately increased efficiency. These findings show that a 1‐month stored SnO2 solution treated with acetic acid produces a device with a photoelectric conversion efficiency (PCE) of 20.9%, compared to 13.5% efficiency without treatment. With the addition of PEAI, the champion efficiency of the acetic acid‐treated device is 22.3%. This study provides a simple and effective engineering approach to fabricating high‐performance and stable ETLs for perovskite solar cells.

Mechanistic Insight into the Precursor Chemistry of Cesium Tin Iodide Perovskite Nanocrystals

Colloidal tin halide perovskite nanocrystals (NCs) are of interest as an alternative to their lead-based counterparts. While some advancements have been achieved in their synthetic development, the reaction mechanism, especially the precursor chemistry, of tin halide perovskite NCs remains poorly understood. Here, using cesium tin iodide (CsSnI3) perovskite NCs as a model system, we report on the mechanistic insight into the precursor chemistry of tin-based perovskite NCs through a combination of infrared, mass spectrometry, and nuclear magnetic resonance spectroscopy. We identify that the active intermediate complexes, polymeric alkanoate iodides that form via the reaction of the iodide source with oligomers present in the tin(II) carboxylates, play a key role in governing the reactivity of the tin iodide precursor, which leads to the variation in the size, size uniformity, and photoluminescence quantum yield of CsSnI3 NCs. Our work underscores the importance of understanding the precursor chemistry as a key parameter to design and synthesize tin halide perovskite NCs, which not only aids in their syntheses by design but also might benefit the fabrication of high-quality polycrystalline tin-based films.

Synthesis and elucidation of local structure in phase-controlled colloidal tin phosphide nanocrystals from aminophosphines

Aminophosphines are a class of inexpensive, environmentally benign phosphorus precursors that have provided routes to various metal phosphides. In this work, we use the aminophosphine tris(diethyl)aminophosphine to synthesize tin phosphide nanocrystals.

Modulation of the optical bandgap and photoluminescence quantum yield in pnictogen (Sb3+/Bi3+)-doped organic–inorganic tin(IV) perovskite single crystals and nanocrystals

Water-stable, lead-free zero-dimensional (0D) organic–inorganic hybrid colloidal tin(IV) perovskite, A2SnX6 (A is a monocationic organic ion and X is a halide) nanocrystals (NCs) with high photoluminescence (PL) quantum yield (QY) have rarely been explored. Herein, we report solution-processed colloidal NCs of blue light-emitting T2SnCl6 and orange light-emitting T2Sn1-xSbxCl6 [T+ = tetramethylammonium cation] from their corresponding single crystals (SCs). These colloidal NCs are well-dispersible in non-polar solvents, thereby maintaining their bright emission. This paves the way for fabricating homogeneous thin films of these NCs. Due to organic cation (T+)-controlled large spin–orbit coupling (SOC), the T2Sn1-xSbxCl6 NCs exhibit bright orange emission with an enhancement in PL QY of 41% compared to their bulk counterpart. Furthermore, we explore T2Sn1-xBixCl6 and T2Sn1-x-yBixSbyCl6 SCs, which show blue and green emission, respectively; the latter is attributed to the newly formed Sb 5p and Sb 5 s orbital-driven band structures confirmed by applying density functional theory (DFT) calculations. The SCs and NCs exhibit excellent stability in water under ambient conditions because of the in-situ generation of a hydrophobic and oxygen-resistant passivating layer of oxychloride in the presence of water. Our findings open a pathway for designing lead-free perovskites materials for thin-film-based optoelectronic devices.

Synthesis of Tin Oxide Nanoparticles by Pulsed Laser Ablation Method Using Low-Energy Nd: YAG Laser as an Antibacterial Agent

Tin oxide nanoparticles (SnNPs) are very useful to be employed as an antibacterial agent for both gram-positive and gram-negative bacteria. In this present work, the synthesis of SnNPs was successfully carried out using the neodymium yttrium aluminum garnet (Nd:YAG) laser with a wavelength of 1064 nm, pulse duration of 7 ns, and a laser frequency of 10 Hz. Experimentally, a pulse Nd:YAG laser was directed and focused on a high-purity tin (Sn) metal, immersed in various liquid media including pure water and ethylene glycol. A brownish colloidal colour was produced both in pure water and ethylene glycol liquid media. Characterizations of tin oxide nanoparticles were made using UV-Vis, EDX, FTIR, and TEM. UV-Vis characterization produced absorbance values in pure water and ethylene glycol media of 1.314 a.u. and 1.119 a.u., respectively. TEM images show that the shape of tin oxide nanoparticles produced is spherical. Measurement of nanoparticle size distribution was made using image-J software and the average diameter of nano-size in the ethylene glycol medium is 12.55 nm, which is smaller than the size in the pure water of 19.98 nm. The EDX spectrum analysis results show that there are only Sn and O atoms in colloidal tin oxide nanoparticles (SnNPs). FTIR results show the formation of tin oxide (SnO2) spectrum at the wavenumber of 629.03 cm-1. The produced colloidal SnNPs were then applied as an antibacterial agent of E. coli using the disk diffusion method. Results certified that various concentrations of SnNPs of 10 ppm, 20 ppm, and 30 ppm gain the diameter of inhibition zone (DIZ) in sequence 6.50 mm, 6.75 mm, and 9.50 mm. Based on these experimental results, it shows that the higher the concentration of SnNPs given, the greater the ability to degrade and inhibit bacteria.

QCM-based humidity sensor and sensing properties employing colloidal SnO2 nanowires

In this paper, a quartz crystal microbalance (QCM)-based humidity sensor has been fabricated by colloidal tin oxide (SnO2) nanowires. The SnO2 nanowires were synthesized via a colloidal process that employing SnCl4 ethanol solutions mixed with oleic acid (OA) and oleylamine (OLA). The spin-coating method was chosen to deposit the sensitive film at room temperature without high-temperature sintering. Furthermore, the Cu(NO3)2 methanol solution was used to remove the organic long chains coated on the surface of the colloidal SnO2 nanowires and expose more adsorption sites. The characterizations of the material were studied by means of FTIR, XRD, and FE-SEM. The saturated salt solution method was used to investigate the humidity sensing performance (response, recovery, repeatability, etc.) of the QCM sensor in the range of 11%–97%. The results showed that the sample with 12 h synthesis has the best humidity response. This may be attributed to the larger specific surface area which makes the material provide more adsorption sites for water molecules, and more (110) planes formed which could absorb more water molecules proved by the Density Functional Theory (DFT) calculation.

Freestanding SnO2 films produced with anodic polarization in acidic media containing colloidal tin hydroxides

Abstract Within the scope of the study, we aimed to develop a strategy for production of thick self -supporting tin oxide films with high surface area by anodic oxidation of metallic tin in acidic solutions. This has not been achieved before because of the highly porous and non-adherent nature of the oxidation products and high dissolution rate of tin in acidic solutions. Entrapment of the gelatinous colloidal tin hydroxides in the film during anodic oxidation exerted the necessary effect for decreasing the permeability of the oxide and dissolution of tin. Below this adherent and semi permeable film, a tin ion supersaturated zone was created, enabling the whisker type growth of complex tin oxyhydroxides at the metal/oxide interface. Colloidal +4 valent acid insoluble tin hydroxides are prepared by oxidation of dissolved Sn+2 ions in sulfuric acid solution with H2O2. Moreover by utilizing this approach growing 100–150 μm thick layers was possible, which were easily detached as free standing film from the underlying tin anode. The structure, chemistry and morphology of the films produced by anodic oxidation in acidic solutions were determined by using micro Raman spectroscopy, X-Ray diffraction (XRD) and SEM. Since the films produced by the above stated method consisted of a complex mixture of oxides, hydroxides and sulfates, annealing treatment was applied to convert these structures into stoichiometric SnO2.

Preparation of colloidal Tin sulfide nanoparticles by Pulse Laser Ablation in Liquid (PLAL)

Preparation of colloidal Tin sulfide nanoparticles by Pulse Laser Ablation in Liquid (PLAL)

Splenic implant preservation after conservation in lactated Ringer´s solution.

to evaluate the morphology and function of autogenous splenic tissue implanted in the greater omentum, 24 hours after storage in Ringer-lactate solution. we divided 35 male rats into seven groups (n=5): Group 1: no splenectomy; Group 2: total splenectomy without implant; Group 3: total splenectomy and immediate autogenous implant; Group 4: total splenectomy, preservation of the spleen in Ringer-lactate at room temperature, then sliced ​​and implanted; Group 5: total splenectomy, ​​spleen sliced and preserved in Ringer-lactate at room temperature before implantation; Group 6: total splenectomy with preservation of the spleen in Ringer-lactate at 4°C and then sliced ​​and implanted; Group 7: total splenectomy and the spleen sliced for preservation in Ringer-lactate at 4°C before implantation. After 90 days, we performed scintigraphic studies with Tc99m-colloidal tin (liver, lung, spleen or implant and clot), haematological exams (erythrogram, leucometry, platelets), biochemical dosages (protein electrophoresis) and anatomopathological studies. regeneration of autogenous splenic implants occurred in the animals of the groups with preservation of the spleen at 4ºC. The uptake of colloidal tin was higher in groups 1, 3, 6 and 7 compared with the others. There was no difference in hematimetric values ​​in the seven groups. Protein electrophoresis showed a decrease in the gamma fraction in the group of splenectomized animals in relation to the operated groups. the splenic tissue preserved in Ringer-lactate solution at 4ºC maintains its morphological structure and allows functional recovery after being implanted on the greater omentum.

Colloidal tin sulfide nanosheets: formation mechanism, ligand-mediated shape tuning and photo-detection

Colloidal materials of tin(ii) sulfide (SnS), as a layered semiconductor with a narrow band gap, are emerging as a potential alternative to the more toxic metal chalcogenides (PbS, PbSe, CdS, and CdSe) for various applications such as electronic and optoelectronic devices.

Charge Carrier Dynamics and Mobility Determined by Time-Resolved Terahertz Spectroscopy on Films of Nano-to-Micrometer-Sized Colloidal Tin(II) Monosulfide.

Tin(II) monosulfide (SnS) is a semiconductor material with an intermediate band gap, high absorption coefficient in the visible range, and earth abundant, non-toxic constituent elements. For these reasons, SnS has generated much interest for incorporation into optoelectronic devices, but little is known concerning the charge carrier dynamics, especially as measured by optical techniques. Here, as opposed to prior studies of vapor deposited films, phase-pure colloidal SnS was synthesized by solution chemistry in three size regimes, ranging from nanometer- to micron-scale (SnS small nanoparticles, SnS medium 2D nanosheets, and SnS large 2D μm-sheets), and evaluated by time-resolved terahertz spectroscopy (TRTS); an optical, non-contact probe of the photoconductivity. Dropcast films of the SnS colloids were studied by TRTS and compared to both thermally annealed films and dispersed suspensions of the same colloids. TRTS results revealed that the micron-scale SnS crystals and all of the annealed films undergo decay mechanisms during the first 200 ps following photoexcitation at 800 nm assigned to hot carrier cooling and carrier trapping. The charge carrier mobility of both the dropcast and annealed samples depends strongly on the size of the constituent colloids. The mobility of the SnS colloidal films, following the completion of the initial decays, ranged from 0.14 cm2/V·s for the smallest SnS crystals to 20.3 cm2/V·s for the largest. Annealing the colloidal films resulted in a ~ 20 % improvement in mobility for the large SnS 2D μm-sheets and a ~ 5-fold increase for the small nanoparticles and medium nanosheets.

Polymer-inorganic coatings containing nanosized sorbents selective to radionuclides. 2. Latex/tin oxide composites for cobalt fixation.

Colloidal tin oxide with an average particle size of 3.5 nm, which was ex-situ synthesized by the sol-gel method, has been attached to the surface of amino-functionalized poly(acrylate-co-silane) latex particles with a diameter of 100 nm to yield a composite with selective sorption properties toward Co(2+) ions. Electrokinetic properties and the colloidal stability of the synthesized latex/SnO2 composites have been evaluated in dependence on SnO2 content and pH; the sorption capacity and distribution coefficients of composites for Co(2+) ions were in accordance with the SnO2 content and its sorption performance as an individual compound. Composite coatings obtained by casting latex/SnO2 dispersions on quartz sand spiked with (57)Co radionuclide have efficiently eliminated radionuclides migration from the surface when the SnO2 volume fraction in the film was 3.5-4.7%. Furthermore, at these SnO2 loadings, the composite coatings retained the coherent structure of the original latex coating with SnO2 particles homogeneously distributed over the film thickness. The presence of competing Ca(2+) ions in the leaching media at a concentration of above 0.01 mol/L results in a decrease of the distribution coefficients of the latex/SnO2 composite and significantly higher (57)Co leaching. The value of the distribution coefficient of the sorption material to be used in latex composite coatings to prevent migration of radionuclides shall be close to 10(6) mL/g.

Optical properties of tin oxide nanoparticles prepared by laser ablation in water: Influence of laser ablation time duration and laser fluence

Abstract Colloidal tin oxide nanoparticles are prepared by laser (having a wavelength of 1064 nm) ablation of tin metallic target immersed in pure deionized water. The influences of laser ablation time and laser fluence on the size and optical properties of the synthesized nanoparticles are studied. Prepared tin oxide nanoparticles are characterized by transmission electron microscope, selected area electron diffraction and UV–Visible absorption spectroscopy. The morphology of prepared tin oxide nanoparticles is found to be mostly spherical and with sizes in the nanometric range (mean radius of 3.2 to 7.3 nm). The measured UV–Visible absorption spectra show the presence of absorption peaks in the ultraviolet region. The band gap energy of samples prepared with different laser ablation time duration is calculated and is found to be increased with decrease in size (radius) of the prepared nanoparticles. Photoluminescence emission measurements at room temperature show that all the samples exhibit photoluminescence in the visible region. The peak photoluminescence emission intensity in the sample prepared with 50 min of laser ablation time is 3.5 times larger than that obtained in the sample prepared with 10 min of laser ablation time.

A new preparation of colloidal 99mTc-Tin phosphate stabilized with CMC as lyophilized kit for bone Marrow Scintigraphy

The new preparation of colloidal Tin phosphate labeled with technisum- 99m for bone marrow studies. The method was applied with heating sodium bihydrogen phosphate with carboxy methyl cellulose (CMC) as stabilizer in neutral medium then cooed at room temperature, followed by adding stannouschloride as stannite. The chemical analysis indicates that the radiochemical purity is greater than 99% with suitable particle size distribution.The results of biodistribution indicate that the preparative agent was accumulated with higher concentration in bone marrow reach to 30% of total injected dose and negligible percent in non target organs. The results meaning that the new preparative agent is a good agent for using as bone marrow scintigraphy compared with others.

An evaluation of GMCP‐SA as a replacement for ITLC‐SG when measuring the levels of radiochemical impurities in 99mTc radiopharmaceuticals by thin‐layer chromatography

AbstractBackground: The European Pharmacopoeia and radiopharmaceutical manufacturers specify Instant Thin‐Layer Chromatography Silica Gel impregnated glass fibre (ITLC‐SG) as the stationary phase for measuring the radiochemical purity (RCP) of most technetium‐99m (99mTc) radiopharmaceuticals. During 2008, The Pall Corporation stopped manufacturing ITLC‐SG. A replacement is required. Aim: To evaluate Varian's Glass Microfibre Chromatography Paper impregnated with salicic acid (GMCP‐SA) as a replacement. Experimental: Samples of six 99mTc radiopharmaceuticals (albumin nanocolloid, colloidal tin, exametazime, medronate, pentetate and succimer) were prepared containing levels of radiochemical impurities between 0 and 10%. Samples were tested using ITLC‐SG and GMCP‐SA with the mobile phase specified in the pharmacopoeia or by the manufacturer. Analysis was performed by thin‐layer radiochromatogram scanning. Results: For measuring the RCP of albumin nanocolloid, colloidal tin, exametazime and succimer, GMCP‐SA is a suitable replacement for ITLC‐SG. For medronate, GMCP‐SA is suitable for measuring colloidal 99mTc impurity despite producing slightly higher values than ITLC‐SG, but unsuitable for measuring 99mTc pertechnetate impurity due to significant over‐estimation. For pentetate, GMCP‐SA is suitable for measuring colloidal 99mTc impurity but gives slightly higher values for 99mTc pertechnetate impurity than ITLC‐SG. Conclusion: GMCP‐SA is a suitable alternative to ITLC‐SG for analysing some 99mTc radiopharmaceuticals but is not a universal replacement. Copyright © 2009 John Wiley & Sons, Ltd.

Influence of colloid particle profile on sentinel lymph node uptake

Particle size of colloids employed for sentinel lymph node (LN) detection is not well studied. This investigation aimed to correlate particle size and distribution of different products with LN uptake. All agents (colloidal tin, dextran, phytate and colloidal rhenium sulfide) were labeled with (99m)Tc according to manufacturer's instructions. Sizing of particles was carried out on electron micrographs using Image Tool for Windows (Version 2.0). Biodistribution studies in main excretion organs as well as in popliteal LN were performed in male Wistar rats [30 and 90 min post injection (p.i.)]. The injected dose was 0.1 ml (37 MBq) in the footpad of the left posterior limb. Dynamic images (0-15 min p.i.) as well as static ones (30 and 90 min) were acquired in gamma camera. Popliteal LN was clearly reached by all products. Nevertheless, particle size remarkably influenced node uptake. Colloidal rhenium sulfide, with the smallest diameter (5.1 x 10(-3)+/-3.9 x 10(-3) microm), permitted the best result [2.72+/-0.64 percent injected dose (%ID) at 90 min]. Phytate displayed small particles (<15 microm) with favorable uptake (1.02+/-0.14%ID). Dextran (21.4+/-12.8 microm) and colloidal tin (39.0+/-8.3 microm) were less effective (0.55+/-0.14 and 0.06+/-0.03%ID respectively). Particle distribution also tended to influence results. When asymmetric, it was associated with biphasic uptake which increased over time; conversely, symmetric distribution (colloidal tin) was consistent with a constant pattern. The results are suggesting that particle size and symmetry may interfere with LN radiopharmaceutical uptake.

Deposited debris characteristics and its reduction of a laser-produced plasma extreme ultraviolet source using a colloidal tin dioxide jet target

Debris characteristics and their reduction have been investigated for a laser-produced plasma extreme ultraviolet source by using a colloidal jet target containing tin dioxide nanoparticles. The amounts of deposited debris on a witness plate were determined by total laser energy irradiated onto a target. In situ low-temperature (100°C) heating of a plate was effective to reduce the amounts of deposited debris, since colloidal debris was easily vaporized by the heat.

Orbital Drainage of Different Sizes of Colloids in Rabbits: A Dynamic Scintigraphic Study

To investigate the drainage patterns of radiolabeled colloids of different sizes injected into the orbital cavity in an animal model. Twenty-one orbits of 11 rabbits were included in the study. In group 1, human serum macroaggregates with particle sizes of 10 to 100 microm, labeled with 10 mL of 1480 MBq (40 mCi) technetium pertechnetate Tc 99m (99mTc), were used. In group 2, human serum albumin colloidal particles with particle sizes of 50 to 80 nm, labeled with 5 mL of 740 MBq (20 mCi) 99mTc, were used. In group 3, colloidal tin with particle sizes of 300 to 600 nm, labeled with 9 mL of 1665 MBq (45 mCi) 99mTc, were used. The dynamic acquisition of liver for 10 minutes (120 frames for 5 seconds) in a 128 x 128 matrix was acquired immediately after intraorbital injection and at the end of the second hour. The liver in groups 2 and 3 and the lung in group 1 were visualized in 10 seconds or less in six, five, and four rabbits, respectively. The injected activity persisted in the orbits in varying percentages in all rabbits at the end of acquisition. Intraorbital injections have a great potential for systemic absorption and should not be considered as local pharmaceutical administration.

Labeling efficiency and biodistribution of Technetium-99m labeled nanoparticles: interference by colloidal tin oxide particles

The interference of colloidal tin oxides on the biodistribution of 99mTechnetium radiolabeled chitosan nanoparticles has been overcome by using sodium borohydride instead of commonly used stannous salts as reducing agent for the reduction of 99mTc (VII) to lower valency states. Biodistribution of radiolabeled chitosan nanoparticles prepared by using stannous chloride method revealed localization of the radioactivity mainly in the liver and spleen while that of radiolabeled chitosan nanoparticles prepared by using sodium borohydride method manifested the presence of radioactivity in blood up to an extent of 10% even after 2 h. Interestingly, the reduction of radioactivity in the latter case with the progress of time was not manifested through an increase in activity in the liver. Rather, a time dependent increased accumulation of radioactive materials was observed in the stomach. From the results it has been concluded that the biodistribution is strongly influenced by the presence of colloidal particles of tin oxides and 99mTc labeled chitosan nanoparticles are RES evading and long circulating in blood when Tc (VII) is reduced by sodium borohydride and not by stannous chloride during radiolabeling process.