Triethylamine Detection Research Articles

Sn doping effect on NiO hollow nanofibers based gas sensors about the humidity dependence for triethylamine detection

• Hollow Sn-doped NiO nanofibers are synthesized through a facile electrospinning approach. • The Sn-doped NiO sensor with suitable Sn content (6 at%) shows the highest gas response to triethylamine. • Sn doping concentrations can significantly influence the resistance of sensors in air and in target gas under different RH. • The resistances of the sensor change slightly in target gas under different RH with suitable Sn doping content (6 at%). High stable triethylamine gas sensors under different relative humidity are highly desirable in order to correctly detect the concentrations of target gas. In this study, a series of Sn-doped NiO hollow nanofibers were prepared through a facile electrospinning process followed by heat treatment. Sn doping could inhibit the crystal growth, and the crystal sizes would decrease with the increase of Sn doping concentration. Gas sensing investigation indicates that Sn doping could significantly enhance the gas response towards triethylamine at a relative low temperature. Especially, the gas sensor exhibits the highest response to triethylamine when the doping content of Sn reaches to 6 at%. The response value is about 16.6–100 ppm triethylamine, and it is ∼9.2 times higher than that of pure NiO nanofibers at the same operating temperature. In addition, the resistances of the gas sensors with different doping contents of Sn would change differently in air or in target gas under variable relative humidity. The resistances in target gas are almost unchanged with the increase of relative humidity with the Sn doping content of 6 at%. It is reasonable to speculate that Sn doping can heavily alter the surface state of NiO nanofibers, which is beneficial for the improvement of the gas response and humidity dependence properties.

Confined synthesis of 2D ultrathin ZnO/Co3O4 nanomeshes heterostructure for superior triethylamine detection at low temperature

Two-dimensional (2D) ultrathin and mesoporous Co3O4 nanomeshes modified by ZnO nanocrystals (ZnO/Co3O4) was achieved via in-situ growth of ZIF-8 polyhedral particles on ultrathin ZIF-67 nanosheets, which was synthesized by a salt-template strategy followed by calcination. The ZnO/Co3O4-2 (the molar ratio of Zn/Co is 2) ultrathin nanomeshes heterostructure based sensor exhibits a much higher response (Ra/Rg) of 3.2–5 ppm triethylamine with a shorter response/recovery time of 30/55 s at a low operating temperature of 100 °C compared with pristine Co3O4 and ZnO. The enhanced gas sensing performances of ZnO/Co3O4-2 are attributed to its ultrathin mesoporous nanostructure, the presence of rich oxygen vacancy defects and unique heterojunctions at the ZnO/Co3O4 interface. This research not only provides a solid and universal design strategy for the synthesis of 2D ultrathin nanomeshes but also offers valuable guidance to optimize their gas sensing properties by heterostructure design.

Improved triethylamine sensing properties of fish-scale-like porous SnO2 nanosheets by decorating with Ag nanoparticles

Three dimensional (3D) porous nanostructures assembled by low-dimensional nanomaterials are widely applied in gas sensor according to porous structure which can facilitate the transport of gas molecules. In this work, fish-scale-like porous SnO2 nanomaterials assembled from ultrathin nanosheets with thickness of 16.8 nm were synthesized by a facile hydrothermal route. Then Ag nanoparticles were decorated on the surface of SnO2 nanosheets via one-step method to improve their gas-sensing performances. The sensing properties of pristine SnO2 and Ag/SnO2 nanosheets were investigated intensively. After decorating with Ag nanoparticles, the characteristics of SnO2 based sensor for triethylamine detection were significantly improved. Especially, the Ag/SnO2 based sensor with Ag content of 2 at% exhibited the highest triethylamine sensing sensitivity at optimum work temperature of 170 °C. The improved sensing properties of Ag/SnO2 sensors were attributed to the sensitizing actions of Ag nanoparticles as well as the unique hierarchical porous architecture.

Three-dimensional reduced graphene oxide/cobaltosic oxide as a high-response sensor for triethylamine gas at room temperature

Three-dimensional (3D) reduced graphene oxide (rGO)/cobaltosic oxide (Co3O4) nanocomposites were prepared by a simple and low-cost hydrothermal method. Characterization results confirmed that rGO sheets were self-assembled to form a crosslinked porous network structure and Co3O4 nanoparticles were uniformly attached to the surface of rGO with the specific surface area of 306.49 m2/g. More importantly, the as-obtained 3D rGO/Co3O4 nanocomposites exhibited superior gas sensing property for ultra-low concentration detection of triethylamine (TEA) at room temperature; this was because of the mesoporous structure, large specific surface area, and excellent charge carrier transport properties of the nanocomposites. The response value of the 3D rGO/Co3O4 nanocomposite sensors to 1 ppm TEA gas was approximately 35% at room temperature, with extremely fast response and recovery time. 3D rGO/Co3O4 nanocomposites with excellent sensing performance have potential applications in the field of gas sensors.

Triethylamine Sensing with a Mixed Potential Sensor Based on Ce0.8Gd0.2O1.95 Solid Electrolyte and La1-XSrxMnO3 (x = 0.1, 0.2, 0.3) Sensing Electrodes

Introduction The threshold limit of triethylamine concentration is 10 ppm in air by Occupational Safety and Health Administration (OSHA). In addition, it is reported that the concentration of triethylamine at 7 days is less than 4 ppm from rotten crucian (about 200 g) at room temperature, which indicates a great challenge in meeting the requirements of the food freshness test. Recently, gas sensor with low cost and the ability of in-situ measurement has been used to triethylamine detection. The mixed potential sensor based on Ce0.8Gd0.2O1.95 (GDC) has the advantages of high sensing performance, reliable stability and good moisture resistance, which is expected to realize the real-time detection of triethylamine in the atmospheric environment and microenvironment, and to determine the freshness of fish [1, 2]. Method Fabrication and measurement of the gas sensor The sensor was fabricated utilizing Ce0.8Gd0.2O1.95 (GDC) plates (made by Ningbo Sofman Energy Technology Co., Ltd.). A point-shaped and a narrow stripe-shaped Pt electrode were formed on two ends of the GDC plate using a commercial Pt paste (Sino-platinum Metals Co. Ltd.), and sintered at 900°C. The paste which was mixed by a minimum quantity of deionized water and the sensing materials La1-xSrxMnO3 (x = 0.1, 0.2, 0.3). Next, the resultant paste was applied on the point-shade Pt to form stripe-shaped La1-xSrxMnO3 (x = 0.1, 0.2, 0.3) electrode . Afterward, the device was annealed at 800°C to make a good contact between the sensing electrode and electrolyte. A Pt heater and a linear DC Power Supply (Gwinstek GPD-3303S) were used to provide required heat to regulate the operating temperature of the sensor. Results and Conclusions In this paper, CeO2-based mixed potential sensor with La1-xSrxMnO3 (x = 0.1, 0.2, 0.3) and Pt electrodes was developed for the triethylamine detection. It can be seen from Fig. 1(a) that the response value of S2 is the highest, which is -113 mV, so the optimum substitution amount of Sr element in La1-xSrxMnO3 is 20%. Therefore, the sensing performances of the sensor S2, such as the continuous response, sensitivity, selectivity, repeatability and long-term stability were focused in the following content of this study. The dynamic response/recovery transients of the sensor S2 exposed to triethylamine in a concentration gradient 1-200 ppm is shown in Fig. 1(b). It can be seen from the figure that the response value is gradually increasing in the range of 1-100 ppm. When the concentration is higher than 100 ppm, the response value is basically saturated. The response value of sensor S2 to 100 ppm triethylamine is -113 mV, and the sensor S2 is able to detect 1 ppm triethylamine with a response of -8 mV. As shown in Fig.1(c), the typical 90% response time to 100 ppm triethylamine of the sensor S2 is less than 1 s, and the typical 90% recovery time is 9 s. They are quite short time among time cost of the sensors reported. According to the recovery and response curve for sensor S2 to 1-100 ppm triethylamine, the dependence of ΔV on the logarithm of triethylamine concentration for the sensor is shown in Fig. 1(d). A linear relationship between ΔV and the logarithm of concentration towards 1-100 ppm triethylamine at 580°C is shown in the figure, and the sensor S2 displays a sensitivity of -59.2 mV/decade. Next, the cross-sensitivity response of the sensor S2 to 10 ppm various gases (such as ethanol, methanol, methanol, n-butanol and acetone) is shown in Fig. 1(e). It is obvious that the response value of the sensor S2 to triethylamine is much higher than that to other gases, indicating that the sensor S2 has a good selectivity. The continuous response and recovery transient curve of the sensor S2 to 10 ppm triethylamine in five cycles was studied. As shown in Fig. 1(f), the response values remain basically unchanged in the examined five-time cycles, which indicates that sensor S2 displays good repeatability to 10 ppm triethylamine. As shown in Fig. 1(g), the response value of the sensor S2 to 100 ppm triethylamine is basically unchanged under continuous heating to 580°C during 30 days measurement and the sensor S2 exhibited good stability. Taken together, the presented sensor S2 could be considered as a potential sensor for monitoring triethylamine in atmosphere environment and microenvironment, and determining the freshness of fish.

Visual Detection of Triethylamine and a Dual Input/Output Logic Gate Based on a Eu3+-Complex.

A series of Ln3+-metal centered complexes, Ln(TTA)3(DPPI) (Ln = La, 1; Ln = Eu, 2; Ln = Tb, 3; or Ln = Gd, 4) [(DPPI = N-(4-(1H-imidazo [4,5-f][1,10]phenanthrolin-2-yl)phenyl)-N-phenylbenzenamine) and (TTA = 2-Thenoyltrifluoroacetone)] have been synthesized and characterized. Among which, the Eu3+-complex shows efficient purity red luminescence in dimethylsulfoxide (DMSO) solution, with a Commission International De L’ Eclairage (CIE) coordinate at x = 0.638, y = 0.323 and ΦEuL = 38.9%. Interestingly, increasing the amounts of triethylamine (TEA) in the solution regulates the energy transfer between the ligand and the Eu3+-metal center, which further leads to the luminescence color changing from red to white, and then bluish-green depending on the different excitation wavelengths. Based on this, we have designed the IMPLICATION logic gate for TEA recognition by applying the amounts of TEA and the excitation wavelengths as the dual input signal, which makes this Eu3+-complex a promising candidate for TEA-sensing optical sensors.

0D/2D CdS/ZnO composite with n-n heterojunction for efficient detection of triethylamine

It is imperative to seek for novel materials with pronounced gas sensing performance towards triethylamine for the sake of human health. Herein, we successfully fabricate an outstanding triethylamine sensor based on CdS/ZnO composite with 0D/2D structure, which are prepared by in-situ growth of CdS quantum dots on ultra-thin ZnO nanosheets. The ratios between the two ingredients are adjusted and their effect is evaluated. The optimal sample exhibits the lowest operating temperature of 200 °C, the highest response value of ~20 and the fastest response time of 2 s. Besides, it also has the virtues of durable stability, excellent selectivity and superior anti-interference ability. The mechanism behind the aforementioned intriguing performance is investigated by X-ray photoelectron spectroscopy, Kelvin probe and density function theory (DFT) simulation. All the results verify that the enhanced gas sensing properties are derived from splendid 0D/2D structure, n-n heterojunction and large specific surface area. Additionally, this study opens an avenue for designing sensors with 0D/2D structure.

Carbonized polymer dots activated hierarchical tungsten oxide for efficient and stable triethylamine sensor

Hierarchical metal oxide semiconductors present great potential in detecting toxic and hazardous gases with special emphasis on the regulation of their structures and compositions to advance sensor performance. Herein, marine polysaccharide derived carbonized polymer dots (CPDs) are presented to activate hierarchical tungsten oxide (WO3) as efficient and stable triethylamine sensor. Owing to the promoted receptor and transducer function of the oxide/polymer/carbon heterostructure, the CPDs/WO3 sensor exhibits extraordinary sensing characteristics for triethylamine detection, including higher response (4.3 times), faster response/recovery (4.3 times/2.1 times), lower operating temperature (30 °C) and lower detection limit (2.4 times) as compared with hierarchical WO3 sensor, which are also superior to most of the previous reports related to triethylamine detection. Importantly, the adsorption-desorption kinetic of WO3 is found to be enhanced by 67 times after introducing CPDs, mainly derived from abundant slit-like channels for gas diffuse, desirable defect feature as reactive sites, and favorable 0D–2D interface for charge transfer and transport. This work not only establishes an alternative strategy for promoting metal oxide semiconductor gas sensors but also provides a fundamental understanding of CPDs in gas-sensing field.

Sensing platform of PdO-ZnO-In2O3 nanofibers using MOF templated catalysts for triethylamine detection

New sensing platform of PdO-ZnO-In2O3 nanofibers were prepared by a distinctive catalyst loading method (Pd@ZIF-8). The results of TEM show that Pd nanoparticles is about 2 nm in Pd@ZIF-8 and XPS results demonstrate that it finally exists in the form of ultra-small PdO nanoparticles in composite nanofibers. Pure In2O3 and ZnO-In2O3 nanofibers were subjected to comparative gas-sensing investigation to verify the superiority of the PdO-ZnO-In2O3 nanofibers. The results suggest that sensors fabricated on PdO-ZnO-In2O3 nanofibers show enhanced triethylamine response (Ra/Rg = 386 to 100 ppm triethylamine), great selectivity and excellent response/recover speed (1 s/740 s) at 250℃. Furthermore, the loading amount of PdO is 0.2 mol% which is lower than that of the traditional method. The distinguished triethylamine gas sensing performance of PdO-ZnO-In2O3 nanofibers could be mainly due to the maximizing the depletion effects of ultra-small PdO catalysts, and the heterojunctions between PdO (ZnO) and In2O3. This work not only proves that PdO-ZnO-In2O3 nanofibers have great potential for triethylamine detection, but also indicates that using ZIF-8 template to design high-performance sensitive materials is an effective method.

Highly selective triethylamine sensing based on SnO/SnO2 nanocomposite synthesized by one-step solvothermal process and sintering

SnO/SnO2 nanocomposites were successfully synthesized by one-step solvothermal process and sintering. Their crystal phase, element composition and morphology were characterized in detail by X-ray powder diffraction (XRD), field emission scanning electron microscope (FESEM) and the transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). The results of gas sensing measurement on these synthesized materials indicated that the sample annealed at 300 °C showed excellent triethylamine sensing performance at 225 °C. Its response value to 100 ppm triethylamine is 33, 5 times higher than that of pure SnO2. The response time and detection limitation are 2 s and 500 ppb, respectively, which were lower than many other reported sensors. Additionally, it possessed excellent selectivity to triethylamine as well as good stability and repeatability. The rapid response and high sensitivity to trace triethylamine can be attributed to the high levels of chemisorbed oxygen and defective oxygen sites and the p-n junction between SnO and SnO2. The excellent sensing performance of SnO/SnO2 makes it a potential sensing material for triethylamine detection.

GEA Group, Germany

Three-dimensional (3D) reduced graphene oxide (rGO)/cobaltosic oxide (Co3O4) nanocomposites were prepared by a simple and low-cost hydrothermal method. Characterization results confirmed that rGO sheets were self-assembled to form a crosslinked porous network structure and Co3O4 nanoparticles were uniformly attached to the surface of rGO with the specific surface area of 306.49 m2/g. More importantly, the as-obtained 3D rGO/Co3O4 nanocomposites exhibited superior gas sensing property for ultra-low concentration detection of triethylamine (TEA) at room temperature; this was because of the mesoporous structure, large specific surface area, and excellent charge carrier transport properties of the nanocomposites. The response value of the 3D rGO/Co3O4 nanocomposite sensors to 1 ppm TEA gas was approximately 35% at room temperature, with extremely fast response and recovery time. 3D rGO/Co3O4 nanocomposites with excellent sensing performance have potential applications in the field of gas sensors.

People & Appointments

Three-dimensional (3D) reduced graphene oxide (rGO)/cobaltosic oxide (Co3O4) nanocomposites were prepared by a simple and low-cost hydrothermal method. Characterization results confirmed that rGO sheets were self-assembled to form a crosslinked porous network structure and Co3O4 nanoparticles were uniformly attached to the surface of rGO with the specific surface area of 306.49 m2/g. More importantly, the as-obtained 3D rGO/Co3O4 nanocomposites exhibited superior gas sensing property for ultra-low concentration detection of triethylamine (TEA) at room temperature; this was because of the mesoporous structure, large specific surface area, and excellent charge carrier transport properties of the nanocomposites. The response value of the 3D rGO/Co3O4 nanocomposite sensors to 1 ppm TEA gas was approximately 35% at room temperature, with extremely fast response and recovery time. 3D rGO/Co3O4 nanocomposites with excellent sensing performance have potential applications in the field of gas sensors.

Parker Hannifin Corp, USA

Three-dimensional (3D) reduced graphene oxide (rGO)/cobaltosic oxide (Co3O4) nanocomposites were prepared by a simple and low-cost hydrothermal method. Characterization results confirmed that rGO sheets were self-assembled to form a crosslinked porous network structure and Co3O4 nanoparticles were uniformly attached to the surface of rGO with the specific surface area of 306.49 m2/g. More importantly, the as-obtained 3D rGO/Co3O4 nanocomposites exhibited superior gas sensing property for ultra-low concentration detection of triethylamine (TEA) at room temperature; this was because of the mesoporous structure, large specific surface area, and excellent charge carrier transport properties of the nanocomposites. The response value of the 3D rGO/Co3O4 nanocomposite sensors to 1 ppm TEA gas was approximately 35% at room temperature, with extremely fast response and recovery time. 3D rGO/Co3O4 nanocomposites with excellent sensing performance have potential applications in the field of gas sensors.

Rational design of ordered porous SnO2/ZrO2 thin films for fast and selective triethylamine detection with humidity resistance

Current gas sensors based on metal oxide semiconductors still suffer greatly from the poor selectivity and low tolerance to the high relative humidity (RH). Herein, we report a highly selective and humidity-resistant gas sensor based on SnO2/ZrO2 porous thin films with a three-dimensionally ordered microstructure (3DOM). The 3DOM ZrO2 fabricated by a template method serves as a hydrophobic layer and SnO2 deposited on ZrO2 by atomic layer deposition (ALD) acts as the transducer layer. Gas sensing tests reveal the SnO2/ZrO2 sensor has a decent response to triethylamine (TEA), a highly toxic and flammable chemical widely used in industry. The sensor exhibits an ultrafast response and recovery (∼ 1 s) speed to 20 ppm TEA at an optimum operating temperature of 190 °C. When the RH increases from 50 % to 90 %, the response of SnO2/ZrO2 sensor shows a minor decrease of 18 %, which to our best knowledge surpasses the existing reports on TEA detection under high RH. The humidity resistance is attributed to continuous 3DOM ZrO2 layers, which forms an air hydrophobic layer to suppress water adsorption. Furthermore, the SnO2/ZrO2 sensor also possesses superior selectivity, long-time stability and a low detection limit of 40 ppb, thereby endowing a potential toward practical TEA detection.

Porous ZnSnO3 nanocubes as a triethylamine sensor

• ZnSnO 3 was fabricated by a microwave-assisted hydrothermal method and calcination. • ZnSnO 3 presented a nanocubic and porous structure. • Porous ZnSnO 3 nanocubes presented sensitivity and selectivity to triethylamine. • High response and fast response time toward triethylamine detection were attained. • The sensor showed a low detection limit (∼0.6 ppm) to triethylamine detection. Triethylamine (TEA), a volatile organic compound (VOC), is present in several industrial processes and is harmful to human health. Therefore, the development of highly sensitive TEA sensors is desirable. Semiconductor metal oxides (SMOx) have been widely used for VOCs detection due to their efficiency and feasibility. Herein, we report the template-free synthesis of zinc stannate nanocubes (NC-ZnSnO 3 ) by the microwave-assisted hydrothermal method followed by a calcination step. The sample's sensing properties were investigated for different VOCs (methanol, ethanol, isopropanol, acetic acid, acetone, 2-butanone, acetaldehyde, benzene, toluene, m-xylene, and TEA). The sensor presented an improved selectivity toward TEA, showing the highest response of 57.5 to 100 ppm of TEA with a fast response time of 4 s at the optimum operating temperature of 350 °C. The NC-ZnSnO 3 also showed a low detection limit for TEA of about 0.6 ppm. In summary, this work described an efficient method for producing NC-ZnSnO 3 and demonstrated that this material has high selectivity and sensitivity for TEA detection.

Plasma-induced oxygen vacancies enabled ultrathin ZnO films for highly sensitive detection of triethylamine

Metal oxide semiconductor (MOS) thin films hold great promise for electronic devices such as gas sensors. However, the low surface activity of pristine MOS often leads to inferior sensitivity and the sensitization mechanism of ultrathin MOS films has received rare attention. Herein, we report a high performance gas sensor based on plasma-etched ZnO thin films. The ultrathin ZnO films (20 nm) were deposited on SiO2 wafers by atomic layer deposition (ALD), which enables high-throughput production of sensor devices. The ZnO sensor shows typical n-type conductivity, which is highly variable to the exposure of triethylamine (TEA). Annealing temperature of the films is found to impact the sensor response, revealing calcination at a moderate temperature, i.e. 700 °C, leads to the best response. Further treatment by Ar plasma results in a remarkable decrease of sensor working temperature from 300 °C of untreated films to 250 °C and nearly 4-fold enhancement in the sensor response to 10 ppm TEA. Notably, the plasma-treated ZnO sensor also shows decent response even at room temperature (RT), which has been seldom reported for ZnO-based sensors. Structure and mechanism investigations reveal that the superior sensor properties are derived from the abundant oxygen vacancies generated by Ar plasma etching.

Triethylamine gas sensor based on Pt-functionalized hierarchical ZnO microspheres

Abstract Monitoring and detection of triethylamine (TEA) gas are indispensable to environmental and human safety. However, TEA gas sensor suffers from low response. Herein, unique nanosized-Pt-decorated hierarchical ZnO microspheres were prepared. Compared with pristine ZnO microspheres and Pt-c-ZnO (Pt nanoparticles deposited on commercial ZnO), the obtained Pt-ZnO exhibited the best TEA gas sensing behaviors, in terms of lower working temperature (200 °C), better selectivity and long-term stability. Notably, the response value of Pt-ZnO sensor towards 100 ppm TEA was up to 242, which was 50 and 16-fold higher than those of pristine ZnO and Pt-c-ZnO sensor, respectively. The superior properties were attributed to structural advantages as well as the synergistic effect between Pt and ZnO. The sensing mechanism was thoroughly clarified by the electron-sinker effect of Pt. It was further corroborated by Kelvin probe and density function theory (DFT) simulation. Moreover, higher surface adsorption oxygen activity and lower TEA adsorption energy of this optimal sample were demonstrated by temperature programmed desorption (O2-TPD) and DFT simulation. Based on the aforementioned advantages, Pt-ZnO becomes a satisfactory candidate for TEA gas sensors. Significantly, this work opens a new avenue for the understanding the mechanism for performance enhancement under.

Double-layer capsule of mesoporous ZnO@SnO2 for sensitive detection of triethylamine.

To overcome obstacles such as low response and poor selectivity of pure ZnO and SnO2 gas sensors, the ZnO@SnO2 sensor was synthesized by hydrothermal synthesis. The samples were characterized by XRD, XPS, SEM, HRTEM, N2 adsorption-desorption and other techniques. The results show that ZnO@SnO2 forms an n-n-type heterostructure and presents a double-layer capsule with a size of 0.5-4 μm. The results show that compared with pure ZnO and SnO2, the ZnO@SnO2 sensor exhibits a higher response (138.9) to 50 ppm triethylamine (TEA) at 152°C, which is 19.56 times that of the pure ZnO sensor and 21.7 times that of the SnO2 sensor. It has a short response/recovery time (11/11 s), excellent selectivity and cycling stability. Compared with other volatile organic compounds or gases, it has higher selectivity for TEA detection.

Novel strategy to construct porous Sn-doped ZnO/ZnFe2O4 heterostructures for superior triethylamine detection

The reasonable design of heterostructure is of great significance to the development of high-performance gas sensors for practical applications. Herein, a series of Sn-doped ZnO/ZnFe2O4 (Sn-ZZFO) porous heterostructures were firstly synthesized by doping a certain amount (n wt%) of Sn4+ (n = 1.08, 2.47, and 3.75 for Sn-ZZFO-1–3, respectively) into the Prussian blue analogue (PBA)-derived ZnO/ZnFe2O4 (ZZFO) heterostructure. As a result, the Sn-ZZFO-2 exhibited excellent triethylamine (TEA) sensing performances at 270 °C. Its response value to 10 ppm triethylamine was 28.1, which was ca. 8.0, 4.2 and 4.8 times higher than those of ZZFO, (280 °C), Sn-ZZFO-1 and Sn-ZZFO-3, respectively, and even superior to the most of the ZnO-based, SnO2-based, ZnFe2O4-based and reported ZnO/ZnFe2O4 sensor materials. Moreover, Sn-ZZFO-2 possessed low detection limit (<0.2 ppm), excellent selectivity, and short response and recovery times (9 and 7 s) to TEA. The optimized gas sensing performances to TEA were ascribed to the doping a suitable amount Sn4+ into the ZZFO heterostructure, and the unique Sn-ZZFO-2 multistage pore nanosphere structure. This work highlights an efficient method for preparing porous metal ion doped heterostructures for efficient gas detection.

Unveiling the Electronic Interaction in ZnO/PtO/Pt Nanoarrays for Catalytic Detection of Triethylamine with Ultrahigh Sensitivity.

The detection of harmful volatile organic compounds is of great significance to environmental quality and human health. However, it still remains a challenge to achieve high detection sensitivity at a relatively low temperature. Herein, an ultrasensitive catalytic sensor for the detection of triethylamine (TEA) based on ZnO/PtO/Pt nanoarray thin films was realized. Sensor measurements reveal that the PtO/Pt sensitizer dramatically reduces the working temperature from 195 °C of a pristine ZnO sensor to 125 °C of ZnO/PtO/Pt sensors. The ZnO/PtO/Pt sensors exhibit an extremely high response of 3513 to 50 ppm TEA, which is three orders of magnitude higher than that of pristine ZnO. Meanwhile, an ultralow limit of detection of 8.3 ppb is achieved. The outstanding performances are superior to those in most previous reports on TEA detection. Mechanistic investigations reveal that the outstanding performances are ascribed to the strong electronic interaction between PtO and ZnO and the catalytic spillover effect of Pt.