Browse
Submit Data
Databases
API
Help

Dataset Information

14 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Effect of Unsaturated Sn Atoms on Gas-Sensing Property in Hydrogenated SnO₂ Nanocrystals and Sensing Mechanism.

ABSTRACT: Sensing reaction mechanism is crucial for enhancing the sensing performance of semiconductor-based sensing materials. Here we show a new strategy to enhancing sensing performance of SnO₂ nanocrystals by increasing the density of unsaturated Sn atoms with dangling bonds at the SnO₂ surface through hydrogenation. A concept of the surface unsaturated Sn atoms serving as active sites for the sensing reaction is proposed, and the sensing mechanism is described in detail at atomic and molecule level for the first time. Sensing properties of other metal oxide sensors and catalytic activity of other catalysts may be improved by using the hydrogenation strategy. The concept of the surface unsaturated metal atoms serving as active sites may be very useful for understanding the sensing and catalytic reaction mechanisms and designing advanced sensing sensors, catalysts and photoelectronic devices.

SUBMITTER: Yuan Y

PROVIDER: S-EPMC5430629 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Effect of Unsaturated Sn Atoms on Gas-Sensing Property in Hydrogenated SnO2 Nanocrystals and Sensing Mechanism.

Yuan Y Y Wang Y Y Wang M M Liu J J Pei C C Liu B B Zhao H H Liu S S Yang H H

Scientific reports 20170427 1

Sensing reaction mechanism is crucial for enhancing the sensing performance of semiconductor-based sensing materials. Here we show a new strategy to enhancing sensing performance of SnO2 nanocrystals by increasing the density of unsaturated Sn atoms with dangling bonds at the SnO2 surface through hydrogenation. A concept of the surface unsaturated Sn atoms serving as active sites for the sensing reaction is proposed, and the sensing mechanism is described in detail at atomi ...[more]

PMID: 28450724

Similar Datasets

Incorporating N Atoms into SnO₂ Nanostructure as an Approach to Enhance Gas Sensing Property for Acetone.

Project description:The development of high-performance acetone gas sensor is of great significance for environmental protection and personal safety. SnO₂ has been intensively applied in chemical sensing areas, because of its low cost, high mobility of electrons, and good chemical stability. Herein, we incorporated nitrogen atoms into the SnO₂ nanostructure by simple solvothermal and subsequent calcination to improve gas sensing property for acetone. The crystallization, morphology, element composition, and microstructure of as-prepared products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Electron paramagnetic resonance (EPR), Raman spectroscopy, UV⁻visible diffuse reflectance spectroscopy (UV⁻vis DRS), and the Brunauer⁻Emmett⁻Teller (BET) method. It has been found that N-incorporating resulted in decreased crystallite size, reduced band-gap width, increased surface oxygen vacancies, enlarged surface area, and narrowed pore size distribution. When evaluated as gas sensor, nitrogen-incorporated SnO₂ nanostructure exhibited excellent sensitivity for acetone gas at the optimal operating temperature of 300 °C with high sensor response (Rair/Rgas - 1 = 357) and low limit of detection (7 ppb). The nitrogen-incorporated SnO₂ gas sensor shows a good selectivity to acetone in the interfering gases of benzene, toluene, ethylbenzene, hydrogen, and methane. Furthermore, the possible gas-sensing mechanism of N-incorporated SnO₂ toward acetone has been carefully discussed.

| S-EPMC6474091 | biostudies-literature

Solid-State Method Synthesis of SnO?-Decorated g-C?N? Nanocomposites with Enhanced Gas-Sensing Property to Ethanol.

Project description:SnO?/graphitic carbon nitride (g-C?N?) composites were synthesized via a facile solid-state method by using SnCl?·5H?O and urea as the precursor. The structure and morphology of the as-synthesized composites were characterized by the techniques of X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive spectrometer (EDS), thermogravimetry-differential thermal analysis (TG-DTA), X-ray photoelectron spectroscopy (XPS), and N? sorption. The results indicated that the composites possessed a two-dimensional (2-D) structure, and the SnO? nanoparticles were highly dispersed on the surface of the g-C?N? nanosheets. The gas-sensing performance of the samples to ethanol was tested, and the SnO?/g-C?N? nanocomposite-based sensor exhibited admirable properties. The response value (Ra/Rg) of the SnO?/g-C?N? nanocomposite with 10 wt % 2-D g-C?N? content-based sensor to 500 ppm of ethanol was 550 at 300 °C. However, the response value of pure SnO? was only 320. The high surface area of SnO?/g-C?N?-10 (140 m²·g-1) and the interaction between 2-D g-C?N? and SnO? could strongly affect the gas-sensing property.

| S-EPMC5553421 | biostudies-literature

Hierarchical Nanoporous Sn/SnOx Systems Obtained by Anodic Oxidation of Electrochemically Deposited Sn Nanofoams.

Project description:A simple two-step electrochemical method for the fabrication of a new type of hierarchical Sn/SnOx micro/nanostructures is proposed for the very first time. Firstly, porous metallic Sn foams are grown on Sn foil via hydrogen bubble-assisted electrodeposition from an acidulated tin chloride electrolyte. As-obtained metallic foams consist of randomly distributed dendrites grown uniformly on the entire metal surface. The estimated value of pore diameter near the surface is ~35 µm, while voids with a diameter of ~15 µm appear in a deeper part of the deposit. Secondly, a layer of amorphous nanoporous tin oxide (with a pore diameter of ~60 nm) is generated on the metal surface by its anodic oxidation in an alkaline electrolyte (1 M NaOH) at the potential of 4 V for various durations. It is confirmed that if only optimal conditions are applied, the dendritic morphology of the metal foam does not change significantly, and an open-porous structure is still preserved after anodization. Such kinds of hierarchical nanoporous Sn/SnOx systems are superhydrophilic, contrary to those obtained by thermal oxidation of metal foams which are hydrophobic. Finally, the photoelectrochemical activity of the nanostructured metal/metal oxide electrodes is also presented.

| S-EPMC7152847 | biostudies-literature

Polyaniline/(Ta2O5-SnO2) hybrid nanocomposite for efficient room temperature CO gas sensing.

Project description:Development of efficient CO sensors that can detect low concentration CO at room temperature is of prime importance. Herein, we present a Ta2O5-SnO2-PANI hybrid composite for the efficient sensing of CO at room temperature and at very low concentrations. The material was synthesized by the oxidative polymerization method. The structural and morphological characteristics of the nanostructured (Ta2O5-SnO2)-PANI hybrid composite were examined using p-XRD and FESEM techniques. The oxygen vacancies in the material were confirmed by XPS analysis. The hybrid material exhibited superior CO sensing performance with high sensitivity, low operating temperature, and fast response and recovery time compared to the individual counterparts. The enhanced sensing ability of the hybrid material is accredited to the synergistic properties such as conductivity of PANI, improved oxygen vacancies and the heterostructure formed between the PANI and the (Ta2O5-SnO2) composite. These remarkable features make TaSn : PANI a potential sensor at room temperature for sensing of low concentration CO.

| S-EPMC9132034 | biostudies-literature

Hierarchical highly ordered SnO2 nanobowl branched ZnO nanowires for ultrasensitive and selective hydrogen sulfide gas sensing.

Project description:Highly sensitive and selective hydrogen sulfide (H2S) sensors based on hierarchical highly ordered SnO2 nanobowl branched ZnO nanowires (NWs) were synthesized via a sequential process combining hard template processing, atomic-layer deposition, and hydrothermal processing. The hierarchical sensing materials were prepared in situ on microelectromechanical systems, which are expected to achieve high-performance gas sensors with superior sensitivity, long-term stability and repeatability, as well as low power consumption. Specifically, the hierarchical nanobowl SnO2@ZnO NW sensor displayed a high sensitivity of 6.24, a fast response and recovery speed (i.e., 14 s and 39 s, respectively), and an excellent selectivity when detecting 1 ppm H2S at 250 °C, whose rate of resistance change (i.e., 5.24) is 2.6 times higher than that of the pristine SnO2 nanobowl sensor. The improved sensing performance could be attributed to the increased specific surface area, the formation of heterojunctions and homojunctions, as well as the additional reaction between ZnO and H2S, which were confirmed by electrochemical characterization and band alignment analysis. Moreover, the well-structured hierarchical sensors maintained stable performance after a month, suggesting excellent stability and repeatability. In summary, such well-designed hierarchical highly ordered nanobowl SnO2@ZnO NW gas sensors demonstrate favorable potential for enhanced sensitive and selective H2S detection with long-term stability and repeatability.

| S-EPMC8433378 | biostudies-literature

Real-Time Tunable Gas Sensing Platform Based on SnO2 Nanoparticles Activated by Blue Micro-Light-Emitting Diodes.

Project description:Micro-light-emitting diodes (μLEDs) have gained significant interest as an activation source for gas sensors owing to their advantages, including room temperature operation and low power consumption. However, despite these benefits, challenges still exist such as a limited range of detectable gases and slow response. In this study, we present a blue μLED-integrated light-activated gas sensor array based on SnO2 nanoparticles (NPs) that exhibit excellent sensitivity, tunable selectivity, and rapid detection with micro-watt level power consumption. The optimal power for μLED is observed at the highest gas response, supported by finite-difference time-domain simulation. Additionally, we first report the visible light-activated selective detection of reducing gases using noble metal-decorated SnO2 NPs. The noble metals induce catalytic interaction with reducing gases, clearly distinguishing NH3, H2, and C2H5OH. Real-time gas monitoring based on a fully hardware-implemented light-activated sensing array was demonstrated, opening up new avenues for advancements in light-activated electronic nose technologies.

| S-EPMC11306663 | biostudies-literature

SnO-Sn3O4 heterostructural gas sensor with high response and selectivity to parts-per-billion-level NO2 at low operating temperature.

Project description:Considering the harmfulness of nitrogen dioxide (NO2), it is important to develop NO2 sensors with high responses and low limits of detection. In this study, we synthesize a novel SnO-Sn3O4 heterostructure through a one-step solvothermal method, which is used for the first time as an NO2 sensor. The material exhibits three-dimensional flower-like microparticles assembled by two-dimensional nanosheets, in situ-formed SnO-Sn3O4 heterostructures, and large specific surface area. Gas sensing measurements show that the responses of the SnO-Sn3O4 heterostructure to 500 ppb NO2 are as high as 657.4 and 63.4 while its limits of detection are as low as 2.5 and 10 parts per billion at 75 °C and ambient temperature, respectively. In addition, the SnO-Sn3O4 heterostructure has an excellent selectivity to NO2, even if exposed to mixture gases containing interferential part with high concentration. The superior sensing properties can be attributed to the in situ formation of SnO-Sn3O4 p-n heterojunctions and large specific surface area. Therefore, the SnO-Sn3O4 heterostructure having excellent NO2 sensing performances is very promising for applications as an NO2 sensor or alarm operated at a low operating temperature.

| S-EPMC9056288 | biostudies-literature

Bidimensional Engineered Amorphous a-SnO2 Interfaces: Synthesis and Gas Sensing Response to H2S and Humidity.

Project description:Two-dimensional (2D) transition metal dichalcogenides (TMDs) and metal chalcogenides (MCs), despite their excellent gas sensing properties, are subjected to spontaneous oxidation in ambient air, negatively affecting the sensor's signal reproducibility in the long run. Taking advantage of spontaneous oxidation, we synthesized fully amorphous a-SnO2 2D flakes (≈30 nm thick) by annealing in air 2D SnSe2 for two weeks at temperatures below the crystallization temperature of SnO2 (T < 280 °C). These engineered a-SnO2 interfaces, preserving all the precursor's 2D surface-to-volume features, are stable in dry/wet air up to 250 °C, with excellent baseline and sensor's signal reproducibility to H2S (400 ppb to 1.5 ppm) and humidity (10-80% relative humidity (RH)) at 100 °C for one year. Specifically, by combined density functional theory and ab initio molecular dynamics, we demonstrated that H2S and H2O compete by dissociative chemisorption over the same a-SnO2 adsorption sites, disclosing the humidity cross-response to H2S sensing. Tests confirmed that humidity decreases the baseline resistance, hampers the H2S sensor's signal (i.e., relative response (RR) = Ra/Rg), and increases the limit of detection (LOD). At 1 ppm, the H2S sensor's signal decreases from an RR of 2.4 ± 0.1 at 0% RH to 1.9 ± 0.1 at 80% RH, while the LOD increases from 210 to 380 ppb. Utilizing a suitable thermal treatment, here, we report an amorphization procedure that can be easily extended to a large variety of TMDs and MCs, opening extraordinary applications for 2D layered amorphous metal oxide gas sensors.

| S-EPMC9315963 | biostudies-literature

Design of Reduction Process of SnO2 by CH4 for Efficient Sn Recovery.

Project description:We design a novel method for the CH4 reduction of SnO2 for the efficient recovery of Sn from SnO2 through a study combining theory and experiment. The atomic-level process of CH4-SnO2 interaction and temperature-dependent reduction behavior of SnO2 were studied with a combination of a multi-scale computational method of thermodynamic simulations and density functional theory (DFT) calculations. We found that CH4 was a highly efficient and a versatile reducing agent, as the total reducing power of CH4 originates from the carbon and hydrogen of CH4, which sequentially reduce SnO2. Moreover, as a result of the CH4 reduction of SnO2, a mixture of CO and H2 was produced as a gas-phase product (syngas). The relative molar ratio of the produced gas-phase product was controllable by the reduction temperature and the amount of supplied CH4. The laboratory-scale experimental study confirmed that CH4 actively reduces SnO2, producing 99.34% high-purity Sn and H2 and CO. Our results present a novel method for an efficient, green, and economical recycling strategy for Sn with economic value added that is held by the co-produced clean energy source (syngas).

| S-EPMC5663740 | biostudies-literature

Sn-Doped Rutile TiO2 Hollow Nanocrystals with Enhanced Lithium-Ion Batteries Performance.

Project description:Hollow structures and doping of rutile TiO2 are generally believed to be effective ways to enhance the performance of lithium-ion batteries. Herein, uniformly distributed Sn-doped rutile TiO2 hollow nanocrystals have been synthesized by a simple template-free hydrothermal method. A topotactic transformation mechanism of solid TiOF2 precursor is proposed to illustrate the formation of rutile TiO2 hollow nanocrystals. Then, the Sn-doped rutile TiO2 hollow nanocrystals are calcined and tested as anode in the lithium-ion battery. They deliver a highly reversible specific capacity of 251.3 mA h g-1 at 0.1 A g-1 and retain ∼110 mA h g-1 after 500 cycles at a high current rate 5 A g-1 (30 C), which is much higher than most of the reported work.

| S-EPMC6641342 | biostudies-literature