Acetone Gas Sensor Research Articles

Facile preparation of hierarchical Sb-doped In2O3 microstructures for acetone detection

In this work, the peony-like hierarchical Sb-doped In2O3 flowers with different Sb contents have been successfully fabricated via the oxidization conversion of hydrothermally synthesized In2S3 precursors. The results of the sensing properties indicate that the as-fabricated sensors based on 2 mol% Sb-doped In2O3 hierarchical microstructures exhibit high response (64.3 for acetone with 50 ppm), fast response/recovery time (8/27 s), and long term stability characteristics towards acetone gas. Furthermore, selective detection of acetone can be readily achieved with sensors attached with 2 mol% Sb-doped In2O3 even with other common chemicals such as ethanol, methanol, benzene and ammonia around, which provide insights and strategies for developing novel acetone gas sensors used to monitor air-quality and environmental.

Ultra-sensitive and selective acetone gas sensor with fast response at low temperature based on Cu-doped α-Fe2O3 porous nanotubes

In the present work, the acetone gas sensing material based on pure α-Fe2O3 nanotubes, pure and Cu-doped α-Fe2O3 porous nanotubes were fabricated by electrospinning and annealing processes. Different Cu dopant concentrations are introduced to investigate the dopant’s role in sensing performance. The structures and chemical compositions of the as-prepared products were examined using a series of material characterization methods including XRD, EDS, SEM and nitrogen adsorption–desorption analysis. And the acetone sensing results demonstrate that the gas sensitivity of porous nanotubes is better than nanotubes. Moreover, compared with pure samples, the sensor based on 3.0 wt% Cu-doped α-Fe2O3 porous nanotubes exhibits higher response (99.43/100 ppm) and excellent selectivity towards acetone at 164 °C. Meanwhile, the detection limit can extend down to ppb level (2.2/100 ppb). Additionally, the sensor also shows fast response and recovery time (5/18 s) and good repeatability to acetone. The enhancement of gas sensitivity is ascribed to not only the effective utility of hollow and porous structures, but also the high catalytic activity of the Cu additive.

Multi-shelled ZnCo2O4 yolk-shell spheres for high-performance acetone gas sensor

In the present study, multi-shelled ZnCo2O4 yolk-shell spheres have been successfully prepared by using carbonaceous microspheres as templates. It is found that the multi-shelled ZnCo2O4 yolk-shell spheres based sensor shows optimal sensing performances (response value of 38.2, response/recovery time of 19 s/71 s) toward 500 ppm acetone at 200 °C. In addition, this sensor exhibits a low detection limit of 0.5 ppm acetone (response value of 1.36) and a good selectivity toward hydrogen, methane, ethanol, ammonia and carbon dioxide. Furthermore, it is demonstrated that acetone gas response of multi-shelled ZnCo2O4 yolk-shell spheres is significantly better than that of ZnCo2O4 nanotubes and ZnCo2O4 nanosheets. High acetone response of the multi-shelled ZnCo2O4 yolk-shell spheres is attributed to the enhanced gas accessibility of the multi-shell morphology caused by the small crystalline size and high specific surface area while the short response/recovery time is mainly related to the rapid gas diffusion determined by the highly porous structure. Our work puts forward an exciting opportunity in designing various yolk-shelled structures for multipurpose applications.

Enhanced photoelectric responses induced by visible light of acetone gas sensors based on CuO-ZnO nanocomposites at about room temperature

PurposeThe purpose of this paper is to study the effect of doping, annealing temperature and visible optical excitation on CuO-ZnO nanocomposites’ acetone sensing properties and introduce an attractive candidate for acetone detection at about room temperature.Design/methodology/approachZnO nanoparticles doped with CuO were prepared by sol-gel method, and the structure and morphology were characterized via X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and Brunauer-Emmett-Teller. The photoelectric responses of CuO-ZnO nanocomposites to cetone under the irradiation of visible light were investigated at about 30°C. The photoelectric response mechanism was also discussed with the model of double Schottky.FindingsThe doping of CuO enhanced performance of ZnO nanoparticles in terms of the photoelectric responses and the gas response and selectivity to acetone of ZnO nanoparticles, in addition, decreasing the operating temperature to about 30ºC. The optimum performance was obtained by 4.17% CuO-ZnO nanocomposites. Even at the operating temperature, about 30ºC, the response to 1,000 ppm acetone was significantly increased to 579.24 under the visible light irradiation.Practical implicationsThe sensor fabricated by 4.17% CuO-ZnO nanocomposites exhibited excellent acetone-sensing characteristics at about 30ºC. It is promising to be applied in low power and miniature acetone gas sensors.Originality/valueIn the present research, a new nanocomposite material of CuO-ZnO was prepared by Sol-gel method. The optimum gas sensing properties to acetone were obtained by 4.17% CuO-ZnO nanocomposites at about 30ºC operating temperature when it was irradiated by visible light with the wavelength more than 420 nm.

Room-temperature-operated organic-based acetone gas sensor for breath analysis

The major merits of organic-based sensors include their low cost, room-temperature operation, and small size. However, their sensitivity and selectivity are concerning, especially in the application of breath analysis. In this work, organic-based sensors were developed based on cylindrical nano-pore structures, which enhanced the sensitivity down to ppb levels. The sensing performance was demonstrated both in pure nitrogen and ambient air. The sensor constructed with poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butylphenyl)diphenylamine)] (TFB) exhibited a 5% sensing response to 300 ppb of acetone in ambient air. In addition, the sensor’s response to other major breath components, including nitric oxide, ethanol, carbon dioxide, and ammonia, was also established. The results showed that the TFB sensor also exhibited a good response to ammonia. Therefore, a humidification tube was designed as an ammonia filter to improve selectivity. The concept of integrating a highly sensitive sensor with a customized sensing system shows promise for medical applications.

Synthesis and enhanced acetone gas-sensing performance of ZnSnO3/SnO2 hollow urchin nanostructures

A kind of novel ZnSnO3/SnO2 hollow urchin nanostructure was synthesized by a facile, eco-friendly two-step liquid-phase process. The structure, morphology, and composition of samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption–desorption techniques. The results revealed that many tiny needle-like SnO2 nanowires with the average diameter of 5 nm uniformly grew on the surface of the ZnSnO3 hollow microspheres and the ZnSnO3/SnO2 hollow urchin nanostructures with different SnO2 content also were successfully prepared. In order to comprehend the evolution process of the ZnSnO3/SnO2 hollow urchin nanostructures, the possible growth mechanism of samples was illustrated via several experiments in different reaction conditions. Moreover, the gas-sensing performance of as-prepared samples was investigated. The results showed that ZnSnO3/SnO2 hollow urchin nanostructures with high response to various concentration levels of acetone enhanced selectivity, satisfying repeatability, and good long-term stability for acetone detection. Specially, the 10 wt% ZnSnO3/SnO2 hollow urchin nanostructure exhibited the best gas sensitivity (17.03 for 50 ppm acetone) may be a reliable biomarker for the diabetes patients, which could be ascribed to its large specific surface area, complete pore permeability, and increase of chemisorbed oxygen due to the doping of SnO2.

A fast response & recovery acetone gas sensor based on BiFeO3 nanomaterials with high sensitivity and low detection limit

In present work, BiFeO3 was synthesized at different temperatures (450, 500, 550 °C) by tartaric acid sol–gel method. XRD, SEM and TEM were used to characterize microstructure and morphology of as-prepared BiFeO3. All results indicate that as-prepared BiFeO3 is the nanocrystal with single rhombohedrally distorted perovskite structure with the space group R3c and has irregular shapes and the average grain sizes between 50 and 120 nm. BiFeO3 nanomaterials have a low working temperature of 240 °C and high acetone gas response. Especially for BiFeO3 grown at 500 °C, the sensitivity to 50 ppm acetone is about as high as 30 at 240 °C. The response and recovery time of BiFeO3 sensors is respectively about 5 and 18 s. Moreover, BiFeO3 sensors have a low detection limit and the logarithmic curves of the sensitivity and concentration of BiFeO3 sensors satisfy the linear relationship in the low detection range. These results demonstrate that BiFeO3 can be used as an ideal candidate to fabricate high response acetone sensor. Gas sensing mechanism of BiFeO3 is also discussed on the basis of adsorption and desorption of reducing acetone gas and the reaction with oxygen species on the surface of BiFeO3 nanomaterials. This work can give rise to an interesting choice for researching excellent gas sensing properties of other nonstoichiometric oxides.

Superior acetone gas sensor based on electrospun SnO2 nanofibers by Rh doping

Undoped and 0.2-1.0 mol% Rh-doped SnO2 nanofibers were fabricated using electrospinning combined with calcination treatment. The fibrous morphology of these nanofibers were maintained and the grain size of the SnO2 nanocrystals were greatly decreased after Rh doping. Sensors based on these nanofibers were fabricated through a hot pressing mathod. The gas sensing properties of these nanofibers were investigated systematically. The results indicated that the response to 50ppm acetone of 0.5 mol% Rh-doped SnO2 nanofibers was 60.6, which was 9.6 times higher than that of undoped SnO2 nanofibers. In addition, the Rh-doped SnO2 nanofibers showed a decreased cross-response to ethanol, whereas pure SnO2 naofibers did not show selective detection of ethanol and acetone gases. The doping of Rh ions into SnO2 nanocrystals modulates the electron concentration, and induces the changes of the oxygen vacancies and chemisorbed oxygen of SnO2 naofibers. Thus, the doping of Rh3+ into SnO2 nanofibers should be a promising method for designing and fabricating acetone gas sensor with high gas sensing performance.

Morphology-controlled porous α-Fe2O3/SnO2 nanorods with uniform surface heterostructures and their enhanced acetone gas-sensing properties

Morphology-controlled porous α-Fe2O3/SnO2 nanorods with uniform surface heterostructures have been fabricated by a facile surface modification of rod-like α-Fe2O3 nanomaterials by changing the adding amount of Sn composition, displaying the excellent selectivity and sensitivity of gas-sensing to acetone. The introduction of SnO2 nanoparticles had the great effects on tuning the crystal size, crystallinity, and surface status, as well as the structural stability and phase distribution of α-Fe2O3/SnO2 nanorods. Compared to pure α-Fe2O3, α-Fe2O3/SnO2 heterostructures can exhibit the optimal gas-sensing behavior with the sensitivity up to 53.1 and the response and recovery times decreasing to 9 and 2.5 s at the operating temperature of 260 °C, respectively. The enhanced gas-sensing performance can be mainly attributed to the combination of uniform porous structures, narrow size-distribution, large specific surface area, and heterostructures of the interface between α-Fe2O3 and SnO2.

Acetone gas sensors composed of carbon nanotubes with adsorbed Au nanoparticles on plastic substrate

Carbon nanotubes (CNTs) have been demonstrated to be one of the most interesting materials for gas sensing. This study applies a simple method for the direct transfer of high-density CNTs from a SiO2/Si substrate to a flexible substrate for acetone gas sensing at room temperature. The flexible gas sensor exhibited high sensitivities of 4.63% at room temperature for ambient acetone gas concentrations of 800 ppm, respectively. In addition, the gas response of the CNT-based chemiresistor is attributed to p-type conductivity in the Au-modified semiconducting CNTs. Very good repeatability of the sensor response to gas concentration is demonstrated, representing a major step toward the low-cost large-scale production of this class of device.

Effect of annealing temperature on acetone gas sensor properties based on Ni0.9Co0.1Fe2O4 nanoparticles synthesized by microwave assisted combustion method

Effect of annealing temperature on acetone gas sensor properties based on Ni0.9Co0.1Fe2O4 nanoparticles synthesized by microwave assisted combustion method

Enhanced acetone sensing properties of titanium dioxide nanoparticles with a sub-ppm detection limit

In the present study, a simple hydrothermal approach has been successfully applied for a large scale synthesis of anatase titanium dioxide nanoparticles (TiO2 NPs) using titanium glycolate precursors and is utilized for the fabrication of low-cost high performance acetone (CH3COCH3) gas sensors after corroborating the crystallinity, phase-purity, and surface morphology investigations. Several randomly distributed TiO2 aggregates, composed of NPs, are noticed from morphology analysis. Chemiresistive properties of as-fabricated TiO2 sensors attempted towards host of oxidizing and reducing gases, reveal a superior selectivity to CH3COCH3 with a maximum response of 15.24 (1000ppm) @270°C compared to other target gases. One of the key features of as-fabricated TiO2 sensor is the lowest detection limit of 500ppb to CH3COCH3 with rapid response and recovery times, signifying commercial potential of the developed sensor materials. The effect of operating temperature along with various concentrations of CH3COCH3 on the gas sensing properties of TiO2 sensor has thoroughly been investigated and reported. Finally, the interaction mechanism between the CH3COCH3 molecules and the TiO2 NPs sensor was elaborated in depth for a thorough understanding sensor performance experimentally and supposedly.

Hydrothermal synthesis of Ce-doped hierarchical flower-like In2O3 microspheres and their excellent gas-sensing properties

Pure and 1–5mol% Ce-doped hierarchical flower-like In2O3 microspheres with uniform sizes were synthesized via environment friendly one-step hydrothermal method. Their phase structures, morphologies properties and element composition were investigated by different kinds of techniques, including X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectric spectroscopy (XPS). Their gas-sensing properties were tests for several kinds of Volatile Organic Compounds (VOCs). The results indicated that Ce doping could greatly improve sensing performances of In2O3 gas sensors. Among all the samples (0, 1, 3 and 5mol% Ce-doped In2O3), 3mol% Ce-doped In2O3 exhibited the highest response toward 200ppm acetone at 250°C, having a response of 41.8, which was about 4 times higher than pure In2O3. Furthermore, good repeatability and long term stability were achieved, showing its prospect for excellent acetone gas sensor with high performance.

Acetaminophen and acetone sensing capabilities of nickel ferrite nanostructures

Present work elucidates the gas sensing and electrochemical sensing capabilities of sol–gel-derived nickel ferrite (NF) nanostructures based on the electrical and electrochemical properties. In current work, the choices of target species (acetone and acetaminophen) are strictly governed by their practical utility and concerning the safety measures. Acetone, the target analyte for gas sensing measurement is a common chemical used in varieties of application as well as provides an indirect way to monitor diabetes. The gas sensing experiments were performed within a homemade sensing chamber designed by our group. Acetone gas sensor (NF pellet sensor) response was monitored by tracking the change in resistance both in the presence and absence of acetone. At optimum operating temperature 300 °C, NF pellet sensor exhibits selective response for acetone in the presence of other common interfering gases like ethanol, benzene, and toluene. The electrochemical sensor fabricated to determine acetaminophen is prepared by coating NF onto the surface of pre-treated/cleaned pencil graphite electrode (NF-PGE). The common name of target analyte acetaminophen is paracetamol (PC), which is widespread worldwide as a well-known pain killer. Overdose of PC can cause renal failure even fatal diseases in children and demand accurate monitoring. Under optimal conditions NF-PGE shows a detection limit as low as 0.106 μM with selective detection ability towards acetaminophen in the presence of ascorbic acid (AA), which co-exists in our body. Use of cheap and abundant PGE instead of other electrodes (gold/Pt/glassy carbon electrode) can effectively reduce the cost barrier of such sensors. The obtained results elucidate an ample appeal of NF-sensors in real analytical applications viz. in environmental monitoring, pharmaceutical industry, drug detection, and health monitoring.

Optical excitation-enhanced sensing properties of acetone gas sensors based on Al2O3-doped ZnO

PurposeThe purpose of this research is to synthesize Al2O3-ZnO thick films, study the effect of doping and optical excitation on their sensing properties and introduce an attractive candidate for acetone detection in practice.Design/methodology/approachZnO nanoparticles doped with Al2O3 were prepared by sol-gel method and characterized via X-ray diffraction and field-emission scanning electron microscopy. The sensing properties to acetone were investigated with an irradiation of UV. The sensing mechanism was also discussed with UV-Vis spectroscopy.FindingsThe doping of Al2O3 promoted the sensing response and stability of ZnO nanoparticles. The optimum performance was obtained by 4.96 Wt.% Al2O3-ZnO. The response to acetone (1,000 ppm) was significantly increased to 241.81, even just at an operating temperature of 64°C. It was also demonstrated that optical excitation with UV irradiation greatly enhanced the sensing response and the sensitivity can reach up to 305.14.Practical implicationsThe sensor fabricated from 4.96 Wt.% Al2O3-ZnO exhibited excellent acetone-sensing characteristics. It is promising to be applied in low power and miniature acetone gas sensors.Originality/valueIn the present research, the optimum performance was obtained by 4.96 Wt.% Al2O3-ZnO at a low operating temperature of 64°C. The sensing properties were enhanced significantly with optical excitation, and the sensing mechanism was discussed with UV-Vis spectroscopy which has been reported rarely before.

Coaxial electrospinning heterojunction SnO2/Au-doped In2O3 core-shell nanofibers for acetone gas sensor

SnO2/Au-doped In2O3 core-shell (CS) nanofibers (NFs) were designed and synthesized through a facile coaxial electrospinning method. To investigate its potential application, commercial gas sensor was fabricated and its gas sensing properties were tested. The SnO2/Au-doped In2O3 CS NFs sensor showed enhanced acetone gas sensing properties compared to the Au-doped In2O3 single NFs sensor counterpart. The SnO2/Au-doped In2O3 CS NFs sensor exhibited a high response to acetone at 300°C, whereas Au-doped In2O3 NFs sensor showed a relative low response to acetone at 300°C. Furthermore, the former sensors also showed a fast response speed and a good selectivity to acetone. In addition, the underlying mechanism for the enhanced acetone sensing properties of SnO2/Au-doped In2O3 CS NFs sensor could be attributed to the catalytic activity of Au and the CS structure. The approach and results proposed in this study may contribute to the realization of more sensitive CS structure NFs sensors.

Acetone gas sensors based on ZnO nanostructures decorated with Pt and Nb

In this study, the highly selective acetone gas sensors based on ZnO nanostructures with sputtered Pt and Nb were presented. The ZnO nanostructures were systematically prepared onto alumina substrates by a thermal oxidation technique at a working temperature of 500 °C. Pt and Nb were then coated on the prepared ZnO nanostructures by a DC pulse sputtering technique. Their surface morphologies and chemical compositions were analyzed via field emission scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The ZnO nanostructures exhibited the wire-like structures while the ZnO nanostructures with Pt and Nb decoration (ZnO:Pt and ZnO:Nb) showed the fine particles attaching onto their surfaces. The gas sensing characteristics were evaluated toward acetone, ethanol and ethylene vapor at the operating temperatures of 275–450 °C. The maximum sensor response of sensors based on ZnO:Pt and ZnO:Nb were found upon exposure toward acetone vapor at 1000 ppm concentration with the value of 188.0 and 224.0, respectively. The observed sensor response enhancement in ZnO:Pt sensor is clearly explained by the catalytic effect in the oxygen and acetone adsorption reaction, while the sensor response enhancement in ZnO:Nb sensor is clarified by an adjustment of the depletion layer width to larger at the n-n nanoheterojunction of two semiconductors (ZnO:Nb2O5) leading to the sensor response enhancement with a higher resistance in air.

Porous ZnFe2O4 nanorods with net-worked nanostructure for highly sensor response and fast response acetone gas sensor

Metal oxides with proper pore structure and tiny particle size can be utilized to gas sensor by promoting the diffusion and adsorbed quantity of target gas molecules. Herein, porous ZnFe2O4 nanorods with net-worked nanostructure were synthesized by a simple low-temperature hydrothermal strategy using the ZnFe2(C2O4)3 precursor as self-template. The images of electron microscopy obviously depicted the ZnFe2O4 size of primary particle is around 20nm and abundant through pore structure. In addition, the N2 adsorption-desorption results indicate the specific surface area and the pore size are about 82.01m2/g and 6.5nm, respectively. Furthermore, the gas sensing properties of the porous ZnFe2O4 nanorods were illustrated in detail. Just as expected, the gas sensing measurement revealed that the as-prepared porous ZnFe2O4 nanorods as an acetone gas sensor exhibits high sensor response and fast response speed (the response/recovery time and sensor response of the gas sensor to 100ppm acetone at 260°C are 1/11s and 52.8, respectively). The mechanism of gas sensing properties is discussed related to the large specific surface area, proper pore size and net-worked nanostructure.

Synthesis, characterization and acetone gas sensing applications of Ag-doped ZnO nanoneedles

Herein, we report the simple synthesis, characterization and acetone gas sensing applications of Ag-doped ZnO nanoneedles prepared by facile hydrothermal method. The synthesized nanoneedles were characterized through different characterization techniques to examine its crystallinity, phase structure, morphological, compositional, optical, vibrational and gas sensing properties. The detailed morphological studies revealed that the Ag-doped ZnO nanoneedles are assembled into non-homogeneously distributed flower-shaped structures which are grown in high density. Further characterizations confirmed that the synthesized nanoneedles are pure, possessing well-crystallinity and exhibiting good optical and vibrational properties. The synthesized Ag-doped ZnO nanoneedles were used as functional material to fabricate high sensitive acetone gas sensors. The effect of operating temperature and concentration of the acetone were analyzed for detailed sensing performance of synthesized nanoneedles. By detailed sensing experiments, the response and recovery times of 10s and 21s, respectively were calculated at acetone concentration of 100ppm at an optimized operating temperature of 370°C. A maximum sensitivity of 30.233 was recorded at 370°C operating temperature for 200ppm of acetone for the fabricated acetone sensor based on Ag-doped ZnO nanoneedles.

Highly sensitive and selective ethanol and acetone gas sensors based on modified ZnO nanomaterials

Nowadays, highly sensitive metal oxide semiconductor gas sensors are exerting a growing important influence on the detection of target gases. It is still challenging to get both high sensitivity and selectivity to effectively distinguish gas mixtures. In this study, Mn doped ZnO (MZO) is prepared by a facile co-precipitation method and then further modified by CdO addition. The results show that 2.2mol% MZO has high responses to both acetone and ethanol, while 10 mol% CdO activated 1mol% MZO exhibits excellent sensitivity to ethanol and neglectable response to acetone. This is explained by the enhanced alkalinity of ZnO by the CdO addition expelling acetone from adsorption onto the sensor surface, which is verified by temperature–programmed CO2 desorption. Moreover, the CdO-MZO gas sensor has an optimized working temperature of 240°C, far lower than 340°C of MZO, due to the higher oxidativity as proved by the temperature-programmed H2 reduction. The MZO and CdO-MZO gas sensors are then used as a sensor array to distinguish the ethanol and acetone concentrations in mixtures with varied ratios, showing the promise of the gas sensor property tailoring approach for future high performance gas sensors.