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1.
F. I. Shaikh L. P. Chikhale I. S. Mulla S. S. Suryavanshi 《Journal of Materials Science: Materials in Electronics》2017,28(4):3128-3139
In the present paper we have synthesized pristine and Sr doped SnO2 in order to prepare a selective ethanol sensor with rapid response–recovery time and good repeatability. Pristine as well as Sr (2, 4 and 6 mol%) doped SnO2 nanostructured powder was synthesized by using a facile co-precipitation method. The samples were characterized by TG–DTA, XRD, HR-TEM, SAED, FEG-SEM, SEM–EDAX, XPS, UV–Vis and FTIR spectroscopy techniques. The gas response performance of sensor towards ethanol, acetone, liquid petroleum gas and ammonia has been carried out. The results demonstrate that Sr doping in SnO2 systematically decreases crystallite size, increases the porosity and hence enhances the gas response properties of pristine SnO2 viz. lower operating temperature, higher ethanol response and better selectivity towards ethanol. The response and recovery time for 4 mol% Sr doped SnO2 thick film sensor at the operating temperature of 300 °C were 2 and 7 s, respectively. 相似文献
2.
Zhibo Dong Shantang Liu 《Journal of Materials Science: Materials in Electronics》2018,29(4):2645-2653
In this work, ordered mesoporous structures of In2O3-decorated NiO were prepared by a two-step process, comprising of the synthesis of ordered mesoporous NiO followed by injection of In3+ into their pores. The pore size distribution of the as prepared samples was between 4.1 and 21.1 nm. Furthermore, their sensing performances toward NO2 were tested systematically. The results showed the highest response about 3 towards 15 ppm NO2 sensing at room temperature for 5.0 at.% In2O3-decorated NiO compared to other decorated and pure samples. Moreover, the sensor displayed excellent selectivity towards NO2 in the presence of other interfering gases, such as carbon monoxide, ammonia, ethanol, methanol, formaldehyde, toluene, acetone. The exceptional NO2 sensing performance of the In2O3-decorated mesoporous NiO may be attributed to their high specific surface area and the formation of p–n junction with modified carrier concentration caused by In3+ doping. This method can act as an effective strategy for enhancement of gas-sensing properties of pure metal oxides. 相似文献
3.
C. Sankar V. Ponnuswamy M. Manickam R. Suresh R. Mariappan P. S. Vinod 《Journal of Materials Science: Materials in Electronics》2017,28(6):4577-4585
Pure and cerium (Ce) doped tin oxide (SnO2) thin films are prepared on glass substrates by jet nebulizer spray pyrolysis technique at 450 °C. The synthesized films are characterized by X-ray diffraction (XRD), scanning electron microscopy, energy dispersive analysis X-ray, ultra violet visible spectrometer (UV–Vis) and stylus profilometer. Crystalline structure, crystallite size, lattice parameters, texture coefficient and stacking fault of the SnO2 thin films have been determined using X-ray diffractometer. The XRD results indicate that the films are grown with (110) plane preferred orientation. The surface morphology, elemental analysis and film thickness of the SnO2 films are analyzed and discussed. Optical band gap energy are calculated with transmittance data obtained from UV–Visible spectra. Optical characterization reveals that the band gap energy is found decreased from 3.49 to 2.68 eV. Pure and Ce doped SnO2 thin film gas sensors are fabricated and their gas sensing properties are tested for various gases maintained at different temperature between 150 and 250 °C. The 10 wt% Ce doped SnO2 sensor shows good selectivity towards ethanol (at operating temperature 250 °C). The influence of Ce concentration and operating temperature on the sensor performance is discussed. The better sensing ability for ethanol is observed compared with methanol, acetone, ammonia, and 2-methoxy ethanol gases. 相似文献
4.
Xi-Tao Yin Xing-Min Guo 《Journal of Materials Science: Materials in Electronics》2014,25(11):4960-4966
(Au, Pt, Pd)-loaded and (In, Fe)-doped SnO2 are synthesized by a sol–gel method. The composition, morphology and electrochemical property of the materials were characterized by XRD, SEM and electrochemical workstation, respectively. The results show that Au, Pd loading and In, Fe doping prefer to enhance the selectivity to CO against H2, while Pt loading can enhance the selectivity to H2 against CO. Furthermore, 1 mol% Pt-loaded SnO2 sensor has preferable selectivity to H2 against CO when Pt loading amount is changed. The response time of the Pt-loaded SnO2 sensor to 5,000 ppm H2 is 5 s at 400 °C, which is much shorter than that of pure SnO2 sensor. Meanwhile the effect of operating temperature and Pt loading on n value (the slope of logarithm of response versus logarithm of gas concentration) is studied. The Pt-loaded SnO2 sensor can detect H2 down to 1 ppm. These results show that the Pt-loaded SnO2 sensor is a good candidate for practical H2 sensors. 相似文献
5.
Haojie Duan Yifang Wang Shuo Li Haiying Li Li Liu Liting Du Yali Cheng 《Journal of Materials Science》2018,53(5):3267-3279
Pure and Ho-doped In2O3 nanotubes (NTs) and porous nanotubes (PNTs) were successfully synthesized by conventional electrospinning process and the following calcination at different temperatures. X-ray diffractometry (XRD), thermogravimetric analysis (TGA), Raman spectrometer, energy-dispersive spectroscopy, scanning and transmission electron microscopy were carefully used to investigate the morphologies, structures and chemical compositions of these samples. Their sensing properties toward ethanol gas were studied. Compared with pure In2O3 NTs (response value is 17), pure In2O3 PNTs (response value is 20) demonstrated enhanced sensing characteristics. What’s more, the response of Ho-doped In2O3 PNTs sensors to 100 ppm ethanol was up to 60 at 240 °C, which increased three times more than that of the pure In2O3 PNTs. Additionally, the minimum concentration for ethanol was 200 ppb (response value is 2). The increased gas-sensing ability was attributed not only to the hollow and porous structure, but to the Ho dopant. Furthermore, Ho-doped In2O3 PNTs enable sensor to discriminate between ethanol and the other gas distinctly, particularly acetone that is usually indistinguishable from ethanol. Also, by analyzing XRD, TGA and Raman spectrometer, a possible formation mechanism of porous nanotubes and sensing mechanism were put forward. 相似文献
6.
Gurpreet Singh Maninder Kaur Bindiya Arora Ravi Chand Singh 《Journal of Materials Science: Materials in Electronics》2018,29(2):867-875
In this paper we report doping induced enhanced sensor response of SnO2 based sensor towards ethanol at a working temperature of 200 °C. Undoped and dysprosium-doped (Dy-doped) SnO2 nanoparticles were characterized by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). XRD and Raman results verified tetragonal rutile structure of the prepared samples. It has been observed that crystallite size reduced with increase in dopant concentration. In addition, the particle size has been calculated from Raman spectroscopy using phonon confinement model and the values match very well with results obtained from TEM and X-ray diffraction investigations. Dy-doped SnO2 sensors exhibited significantly enhanced response towards ethanol as compared to undoped sensor. The optimum operating temperature of doped sensor reduced to 200 °C as compared to 320 °C for that of undoped sensor. Moreover, sensor fabricated from Dy-doped SnO2 nanostructures was highly selective toward ethanol which signifies its potential use for commercial applications. The gas sensing mechanism of SnO2 and possible origin of enhanced sensor response has been discussed. 相似文献
7.
Weiting Zhan Wanpei Hu Liangsheng Hu Hongwei Ni Ji Hu Zhe Chen Xiongjie Chen 《Journal of Materials Science: Materials in Electronics》2016,27(10):9989-9995
The synthesis and characterization of SnO2 nanomaterials have been extensively studied as photoelectrodes for the potential applications in optoelectronic devices. In this work, SnO2 nanorods arrays have been synthesized by hydrothermal method on the nanoporous surface of the anodized stainless steel. The prepared SnO2 nanorods of 1.3–1.4 µm in length and 250–350 nm in width, were uniformly distributed on the anodized stainless steel. This one-dimensional SnO2 nanostructure directly fabricated on the substrate provides an electron transfer pathway and a Schottky-type contact, resulting in improved photocatalytic and photoelectrochemical performance. The SnO2 nanorods arrays exhibit fast response towards H2O2 determination, producing a linear range from 100 to 3000 μM with a correlation coefficient of 0.984 and a sensitivity of 0.66 μA cm?2 mM?1. The results indicate the potential applications of SnO2 nanorods arrays as the non-enzymatic H2O2 sensor. 相似文献
8.
Biomorphic tube-like CuO was synthesized using pomelo white flesh as biotemplate for the first time. The sample showed a good selectivity to H2S in gasoline 92#, formaldehyde, CH4, H2, CO, toluene, acetone, and ethanol. Although there was an obvious change in response/recovery time with H2S concentration from 10 ppb to 10 ppm, all the response/recovery times were <60 s. Moreover, the sample exhibited stable detection performance for 5 ppm H2S at room temperature over a testing period of 3 months. The detection levels were uniform during cycling. This outstanding sensing performance is attributed to the unique structure, which was convenient for H2S molecule adsorption and facilitated the transformation of semiconducting p-type CuO to metallic CuS during H2S detection. 相似文献
9.
E. Thamarai Selvi S. Meenakshi Sundar 《Journal of Materials Science: Materials in Electronics》2018,29(1):38-48
Ni-doped SnO2 nanoparticles were synthesized by the microwave oven assisted solvothermal method. The structural characterization was done by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy. The outcomes confirmed that Ni-doped SnO2 nanoparticles have a pure rutile-type tetragonal phase of SnO2 structures with a high degree of crystallization and a crystallite size of 10–14 nm. Popcorn like SEM morphology of the nickel doped sample is shown. Optical characterization was done by UV–Vis spectrometer, fluorescence spectroscopy and electron paramagnetic resonance spectroscopy. Magnetic characterization was done by vibrating sample magnetometer (VSM). The VSM measurements revealed that the Ni doped SnO2 powder samples were diamagnetic at room temperature. This diamagnetic result is in contradiction to earlier published results. 相似文献
10.
In the paper, water-dispersed graphene-GQDs composites were prepared by electrochemical exfoliation under alternating voltage combining ultrasonic treatment. The effects of alternating voltage, alternating frequency and the distance between electrodes were carefully explored. The results showed that the quality of composites prepared by alternating voltage was higher than that by direct voltage. The existence of graphene quantum dots (GQDs) hindered the agglomeration of graphene and facilitated dispersion of graphene in water. The sensor based on the obtained graphene-GQDs composites was used to detect dopamine (DA). The electrochemical investigation showed that the sensor had good selectivity and wide linear ranges for the detection of DA (0.1–100 µM). The detection limit could be down to 3 × 10?8 M (S/N = 3) with a sensitivity of 14.25 µA µM?1 cm?2. 相似文献
11.
Functionalized Graphene Quantum Dot Modification of Yolk–Shell NiO Microspheres for Superior Lithium Storage
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Xiaojie Yin Hengqiao Chen Chuanwei Zhi Weiwei Sun Li‐Ping Lv Yong Wang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(22)
Yolk–shell NiO microspheres are modified by two types of functionalized graphene quantum dots (denoted as NiO/GQDs) via a facile solvothermal treatment. The modification of GQDs on the surface of NiO greatly boosts the stability of the NiO/GQD electrode during long‐term cycling. Specifically, the NiO with carboxyl‐functionalized GQDs (NiO/GQDs? COOH) exhibits better performances than NiO with amino‐functionalized GQDs (NiO/GQDs? NH2). It delivers a capacity of ≈1081 mAh g?1 (NiO contribution: ≈1182 mAh g?1) after 250 cycles at 0.1 A g?1. In comparison, NiO/GQDs? NH2 electrode holds ≈834 mAh g?1 of capacity, while the bald NiO exhibits an obvious decline in capacity with ≈396 mAh g?1 retained after cycling. Except for the yolk–shell and mesoporous merits, the superior performances of the NiO/GQD electrode are mainly ascribed to the assistance of GQDs. The GQD modification can support as a buffer alleviating the volume change, improve the electronic conductivity, and act as a reservoir for electrolytes to facilitate the transportation of Li+. Moreover, the enrichment of carboxyl/amino groups on GQDs can further donate more active sites for the diffusion of Li+ and facilitate the electrochemical redox kinetics of the electrode, thus together leading to the superior lithium storage performance. 相似文献
12.
Dang Thi Thanh Le Nguyen Van Duy Ha Minh Tan Do Dang Trung Nguyen Ngoc Trung Phung Thi Hong Van Nguyen Duc Hoa Nguyen Van Hieu 《Journal of Materials Science》2013,48(20):7253-7259
The junction-bridging structure of metal oxide nanowires (NWs) improves gas-sensing properties. In this study, an on-chip growth method was used to fabricate gas sensors, it easily and effectively controls NW junctions. SnO2 NWs were synthesized by thermal evaporation at 800 °C with tin powder as the source. The density of the NW junctions was controlled by changing the mass of the source material. A source material with large mass yielded high-density NW junctions. With electrode spacing of 20 μm, NW junctions were formed from the source material of larger than 2 mg. Gas sensing results revealed that the junction sensors exhibited a good response to NO2 gas at a concentration of 1–10 ppm. The sensors exhibited a good response to NO2 gas at low temperature of up to 100 °C and short response–recovery time (~20 s). The sensors also had good selectivity to NO2 gas. The response (R gas /R air) to 1 ppm NO2 was as high as 22 at 100 °C, whereas the cross gas responses (R air /R gas) to 10 ppm CO, 10 ppm H2S, 100 ppm C2H5OH, and 100 ppm NH3 were negligible (1.1–1.3). 相似文献
13.
Xi-Tao Yin Pin Lv Jing Li 《Journal of Materials Science: Materials in Electronics》2018,29(22):18935-18940
The (Pd, Fe)-modified SnO2 (S1) and Pt-loaded SnO2 (S2) are synthesized via a sol–gel method. As S1 has better selectivity to CO against H2 while S2 to H2 against CO at 400 °C. Thus S1 and S2 can be used to detect the concentration of CO and H2, respectively. However, neither S1 nor S2 can detect the concentration of CO and H2 when they coexist. In this paper, S1 and S2 sensors are used simultaneously for mixed gas of CO and H2 detection, and the respective concentration of CO and H2 is calculated. The calculation process is explained as follows: the response of S1 (R1) and S2 (R2) to a fixed concentration of mixed gas of CO and H2 is obtained in experiment, respectively. So we can calculate the concentration of CO and H2 by using simultaneous equations with the independent variable R1 and R2. Contrast real values with calculated values of CO and H2 concentration, the error margin are all less than 5%, which indicates that this method may be a promising candidate for enhancing the selectivity of semiconductor-based gas sensor to two or more gases. 相似文献
14.
SARBANI BASU YEONG-HER WANG C GHANSHYAM PAWAN KAPUR 《Bulletin of Materials Science》2013,36(4):521-533
Pure and fluorine-modified tin oxide (SnO2) thin films (250–300 nm) were uniformly deposited on corning glass substrate using sol–gel technique to fabricate SnO2-based resistive sensors for ethanol detection. The characteristic properties of the multicoatings have been investigated, including their electrical conductivity and optical transparency in visible IR range. Pure SnO2 films exhibited a visible transmission of 90% compared with F-doped films (80% for low doping and 60% for high doping). F-doped SnO2 films exhibited lower resistivity (0· 12 × 10???4 Ω cm) compared with the pure (14·16 × 10???4 Ω cm) one. X-ray diffraction and scanning electron microscopy techniques were used to analyse the structure and surface morphology of the prepared films. Resistance change was studied at different temperatures (523–623 K) with metallic contacts of silver in air and in presence of different ethanol vapour concentrations. Comparative gas-sensing results revealed that the prepared F-doped SnO2 sensor exhibited the lowest response and recovery times of 10 and 13 s, respectively whereas that of pure SnO2 gas sensor, 32 and 65 s, respectively. The maximum sensitivities of both gas sensors were obtained at 623 K. 相似文献
15.
In this paper, we report a solvothermal route to fabricate coralloid hierarchical SnO2 nanostructures. We obtain the product with different surface morphology at different reaction temperature. The breadth and length of the shot rod on the surface change with the temperature. A possible growth mechanism governing the formation of the nanostructures is discussed. Gas sensors based on the as-prepared SnO2 nanostructures exhibit high sensitivity, short recovery time, good reproducibility and linear dependence relation to benzaldehyde/acetone, which is significant for exploiting gas-sensing materials in the future. 相似文献
16.
Lu Liu Miaoliang Huang Zhang Lan Jihuai Wu Guanglu Shang Guijing Liu Jianming Lin 《Journal of Materials Science: Materials in Electronics》2014,25(2):754-759
Mn-doped CdS quantum dot sensitized solar cells based on SnO2 microsphere photoelectrodes are prepared with successive ionic layer adsorption and reaction method. It is found that with Mn-doped CdS quantum dot sensitizers, the photovoltaic performance of the cells based on SnO2 microsphere photoelectrodes can obviously be enhanced. The reasons are owing to the improved light absorption and the expanded light absorption edge by doping Mn in CdS quantum dots. The electrochemical impedance spectroscopy analysis found that the cells with Mn-doped CdS quantum dot sensitized SnO2 microsphere photoelectrodes can efficiently suppress dark reaction, owing to the increased related resistance. Moreover, it is also found that the Mn-doped CdS quantum dot sensitized SnO2 microsphere photoelectrode can increase the electron diffusion lifetime in the cell. The power conversion efficiency of the cell with 4 wt% Mn-doped CdS quantum dot sensitizers can attain to 2.80 %, with 53 % enhancement compared with that of the CdS quantum dot sensitized cell (1.83 %). 相似文献
17.
E. Thamarai Selvi S. Meenakshi Sundar 《Journal of Materials Science: Materials in Electronics》2017,28(20):15021-15032
This paper highlights on the consequence of replacing tetravalent Sn4+ ions of the SnO2 by divalent Mn2+ ions on their structural, optical and magnetic properties. Samples of Sn1?xMnxO2 with x?=?0.01, 0.02, 0.03 and 0.04 were synthesized using microwave irradiated solvothermal process. The X-ray powder diffraction patterns reveal the rutile tetragonal phase of all doped SnO2 samples with no secondary phases. The transmission electron microscopy results show the formation of spherical nanoparticles of size 10–16 nm. Morphological changes were observed by scanning electron microscopy. The functional groups were investigated using Fourier Transform Infrared Spectroscopy studies. Optical studies were carried by UV–Vis Spectroscopy and Fluorescence Spectroscopy. Electron Paramagnetic resonance was used to calculate the Lande splitting factor ‘g’. The magnetic properties were using Vibrating Sample Magnetometer. SnO2 with lower Mn doping shows ferromagnetism. 相似文献
18.
Tianye Wang Wanyi Liu Yunhang Gao Shuxia Liu 《Journal of Materials Science: Materials in Electronics》2017,28(20):14949-14953
In this study, the effects of sodium oleate on synthesis of Bi2WO6/Bi2O3 loaded reduced graphene oxide photocatalyst was studied. The as-prepared composites were characterized by X-ray diffraction, Fourier transform infrared, X-ray photoelectron spectroscopy, UV–visible diffuse reflectance and photoluminescence spectroscopy. The results suggested that addition of sodium oleate not only promoted synthesis of Bi2O3, but also enhanced the reduction of GO to graphene. When the amount of sodium oleate was 4 mol (Bi:SO?=?1:1), Bi2WO6/Bi2O3@RGO to the best visible-light photocatalytic activity can be synthesized by a facile one-step solvothermal process without further reduction reaction. Hence, it indicated that sodium oleate could affect the synthesis of the as-prepared composites and the photocatalytic activity for degradation of RhB. This study did provide not only a facile method to synthesize Bi2WO6/Bi2O3@RGO, but also a method to reduce graphene oxide to graphene. 相似文献
19.
Xiaona Ye Xiaoyun Xu Lingwei Li Shaolin Xue Xiaojing Han Kehui Wang Weikang Zhou Junwei Han Rujia Zou 《Journal of Materials Science: Materials in Electronics》2017,28(2):1159-1167
SnO2 micromaterials were synthesized via hydrothermal method at a temperature of 200 °C for 24 h without employment of catalysts or surfactants. With the dosage of the precursor (SnCl4) increasing, variable microstructures of SnO2, ophiopogon japonicas-like micrograsses, microcones, microflowers and microcorals, were obtained. The as-prepared SnO2 samples were characterized by X-ray diffraction (XRD), scanning electron microscope and energy dispersive spectrometer respectively. XRD results indicated the as-grown SnO2 samples have a tetragonal rutile structure. Among those different morphologies, micrograsses SnO2 exhibited the best field emission performance with a low turn-on field of 1.05 V/µm and a high field enhancement factor of 3880. The results are quite comparable to reported data and strongly imply the micrograsses SnO2 is a potential material for fabricating efficient emitters of display devices and vacuum electronics. 相似文献
20.
L. S. Semko Ya. I. Kruchek Yu. A. Shevlyakov P. P. Gorbik E. I. Oranskaya 《Inorganic Materials》2007,43(4):358-363
Composites of poly(vinyl chloride) (PVC) and TiO2-modified expanded graphite (EG) have been prepared, with TiO2 contents on the EG surface from 0 to 20 wt % and EG contents from 0 to 100%, and their structural, electrical, and gas-sensing properties have been studied. The gas-sensing performance of the composites was assessed using acetone, toluene, ammonia, and ethanol. The results demonstrate that, by varying the composition of the composites, one can control their percolation threshold, electrical properties, and gas-sensing performance (the time needed for the gas response to reach its maximum, adsorption-desorption rate, and selectivity). 相似文献