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1.
Due to the expansion of human production activities, toxic ammonia (NH3) is excessively released into the atmosphere, being a huge threat to human health and the natural environment. Therefore, it is of great significance to design an easy-synthesized gas-sensing material with both good room temperature sensitivity and selectivity for trace-level NH3 detection. Herein, we fabricate a chemiresistive NH3 gas sensor with enhanced performance based on Ni(OH)2/Ti3C2Tx hybrid materials. The Ni(OH)2/Ti3C2Tx hybrid materials are synthesized by an in-situ electrostatic self-assembly method. Attributed to the formation of interfacial heterojunctions and the modulation of carrier density, the Ni(OH)2/Ti3C2Tx hybrid sensor exhibits high response, outstanding repeatability, good selectivity and stability in low concentrations of NH3. Moreover, the Ni(OH)2/Ti3C2Tx hybrid sensor has a higher response to 10 ppm NH3 at the relative humidity of 40% and 60%, which makes it promising for applications in real complex environments with high humidity. Benefitting from the low power consumption and easy fabrication process, the Ni(OH)2/Ti3C2Tx hybrid sensor possesses a broad application prospect in the internet of things (IoT) environmental monitoring.  相似文献   

2.
Two-dimensional layered Ti3C2Tx MXene was prepared through hydrothermal etching method with LiF and hydrochloric (HCl) acid. Ti3C2Tx was further treated with oxygen plasma activated by microwave energy to obtain the activated Ti3C2Tx at different temperatures ranging from 350 °C to 550 °C. The gas-sensing properties of raw Ti3C2Tx and Ti3C2Tx activated with oxygen microwave plasma were tested toward different volatile organic compounds gases. The results indicated that Ti3C2Tx activated at 500 °C exhibited excellent gas-sensing properties at room temperature (25 °C) to 100 ppm ethanol with a value of 22.47, which is attributed to the enhancement of the amount of oxygen functional groups and defects on the MXene Ti3C2Tx film, and in turn to lead to more oxygen molecules adsorption and desorption reaction in the active defect sites. The enhancement of ethanol-sensing performance demonstrated that the activated Ti3C2Tx possess great potential in gas sensing.  相似文献   

3.
《Ceramics International》2022,48(5):6600-6607
Ti3C2Tx, as a novel two-dimensional material, displays promising prospects in NH3 detection at room temperature. However, the NH3 detection limit of pristine Ti3C2Tx is still a major research concern. Therefore, it is important to explore new Ti3C2Tx-based nanocomposites for better NH3-sensing performance. In the present experiment, Ti3C2Tx/In2O3 nanocomposites were successfully synthesized by ultrasonication and characterized by XRD, FESEM, TEM, XPS, and BET. The optimal Ti3C2Tx/In2O3-based sensor had a high response of 63.8% (30.4 times higher than that of pristine Ti3C2Tx) to 30 ppm NH3 at room temperature. In addition, the optimal Ti3C2Tx/In2O3-based sensor had stable repeatability, excellent selectivity, and long-term stability, while exhibiting excellent potential for NH3 detection at room temperature.  相似文献   

4.
《Ceramics International》2022,48(14):20324-20331
As one of the typical MXenes materials, 2D Ti3C2Tx has attracted extensive attention in the field of energy storage. However, due to the restacking problem of Ti3C2Tx nanosheets, the electrochemical performance of Ti3C2Tx is unsatisfactory. In this paper, a scheme is proposed to obtain 3D aerogel with 1D channels by directional freeze drying of Ti3C2Tx. With the help of the unidirectional channels, the 3D Ti3C2Tx/Sodium alginate (SA) aerogel can effectively solve the stacking problem of Ti3C2Tx nanosheets, and it also accelerates the diffusion of ions. The Ti3C2Tx/SA-5 electrode can still reach the mass capacitance of 284.5 F g?1 and the areal capacitance of 4030.4 mF cm?2 at 2 mV s?1 when the loading is 14.2 mg cm?2 in 1 M H2SO4 electrolyte. In addition, the electrode showed good cycling performance without capacitor degradation after 20,000 cycles at 50 mV s?1. These results suggest that by using the strategy of building special 3D structure of 2D MXene with 1D unidirectional channels, high performance supercapacitor electrodes with high mass loading can be realized.  相似文献   

5.
《Ceramics International》2022,48(12):16892-16900
To solve pollution problems caused by electromagnetic waves, advanced three-dimensional (3D) honeycomb Ag/Ti3C2Tx hybrid materials were produced by a microwave hydrothermal method. The Ag/Ti3C2Tx hybrid materials retained their hollow sphere structure after the polymethyl methacrylate (PMMA) template was removed by annealing. The hybrid materials changed from hydrophilic to hydrophobic and exhibited cross-surface heat insulation and reflection-dominant electromagnetic interference shielding (EMIS) performance owing to their special honeycomb structure. This study innovatively explored the influence of different particle sizes of honeycomb holes on EMIS performance. In particular, the Ag/Ti3C2Tx 5 μm hybrid materials had an excellent average EMIS performance of 51.15 dB in the X-band and 56.64 dB in the Ku-band. The superior performance was due to conduction loss, interface polarization, multi-reflection, and scattering caused by the 3D porous structure of the Ag/Ti3C2Tx hybrid materials. In general, Ag/Ti3C2Tx hybrid materials with honeycomb structures retained the advantages of lightweight, hydrophobicity, and EMIS performance, illustrating the great application prospects of these materials in high-end electronic equipment.  相似文献   

6.
《Ceramics International》2022,48(7):9059-9066
Highly active two-dimensional (2D) nanocomposites have been widely concerned in the field of gas sensors because of their unique advantages and synergistic effects. 2D/2D SnO2 nanosheets/Ti3C2Tx MXene nanocomposites were synthesized by using layered Ti3C2Tx MXene and uniform SnO2 nanosheets by hydrothermal method. Characterization results show that the SnO2 nanosheets are well dispersed and vertically anchored on the layered Ti3C2Tx MXene surface, forming heterogeneous interfaces. Based on the gas-adsorption capabilities and synergistic effects of electronic properties, SnO2 nanosheets/Ti3C2Tx MXene nanocomposites show high triethylamine (TEA) gas-sensing performance at low temperature (140 °C). The sensor responses of the nanocomposites and pure SnO2 nanosheets to 50 ppm of TEA are 33.9 and 3.4, respectively. An enhancement mechanism for SnO2 nanosheets/Ti3C2Tx MXene nanocomposites is proposed for highly sensitive and selective detection of TEA at low temperature. The combination strategy of two-dimensional metal oxide semiconductor and multilayer MXene provides a new way for the development of cryogenic gas sensors in the future.  相似文献   

7.
Highly active two-dimensional (2D) nanocomposites, integrating the unique merits of individual components and synergistic effects of composites, have been recently receiving attention for gas sensing. In this work, In2O3 nanocubes/Ti3C2Tx MXene nanocomposites were synthesized using In2O3 nanocubes and layered Ti3C2Tx MXene via a facile hydrothermal self-assembly method. Characterization results indicated that the In2O3 nanocubes with sizes approximately 20–130 nm in width were well dispersed on the surface of layered Ti3C2Tx MXene to form numerous heterostructure interfaces. Based on the synergistic effects of electronic properties and gas-adsorption capabilities, In2O3 nanocubes/Ti3C2Tx MXene nanocomposites exhibited high response (29.6%–5 ppm) and prominent selectivity to methanol at room temperature. Meanwhile, the low detection concentration could be reduced to ppm-level, the response/recovery times are shortened to 6.5/3.5 s, excellent linearity and outstanding repeatability. The strategy of compositing layered MXene with metal oxide semiconductor provides a novel pathway for the future development of room temperature gas sensors.  相似文献   

8.
《Ceramics International》2023,49(18):29962-29970
The few-layered Ti3C2Tx/WO3 nanorods foam composite material was synthesized by electrostatic self-assembly and bidirectional freeze-drying technologies. The phase structure and microstructure of synthesized samples was characterized by XRD, FESEM, TEM and their gas sensing properties estimated via a self-designed equipment with four test channels. The results demonstrate WO3 nanorods were successfully anchored on the surface and between layers of few-layered Ti3C2Tx MXene by electrostatic self-assembly strategy and the composite material simultaneously has a low-density foam morphology by means of bidirectional freeze-drying processes. There exists a typical heterostructure at the interfaces owing to the inseparable contact between the few-layered Ti3C2Tx MXene and WO3 nanorods. Compared with the original WO3 nanorods, the few-layered Ti3C2Tx/WO3 nanorods foam composite material displays excellent gas sensing properties for NO2 detection at low temperature, in particular the optimal value of gas sensing response (Rg/Ra) reaches to 89.46 toward 20 ppm NO2 at 200 °C. The gas sensing mechanism was also discussed. The increase of gas sensitivity is attributed to a fact that during the reaction process of gas sensing, the excellent conductivity of the few-layered Ti3C2Tx MXene provided faster transport channels of free carriers, and the heterojunctions formed by few-layered Ti3C2Tx MXene and WO3 nanorods enhanced the carriers separation efficiency. Meanwhile, the low-density layered structure of few-layered Ti3C2Tx/WO3 nanorods foam composite material provides convenient diffusion paths for gas molecules to the surface of WO3 nanorods.  相似文献   

9.
Ti3C2Tx MXene, an emerging two-dimensional (2D) ceramic material, has rich interfaces and strong conductive networks. Herein, we have successfully built a heterostructure between Ti3C2Tx MXene and WS2 to improve electromagnetic absorption performance. X-ray diffraction and X-ray photoelectron spectroscopy were used to determine the successful synthesis of Ti3C2Tx/WS2 composite. Field emission scanning electron microscopy and transmission electron microscopy images show that WS2 nanosheets are evenly dispersed on the accordion-like Ti3C2Tx MXene. Importantly, Ti3C2Tx MXene/WS2 composite has sufficiently high dielectric loss and impedance matching due to self-adjusting conductivity and 2D heterostructure interfaces. As a result, the Ti3C2Tx/WS2 composite has a minimum reflection loss (RLmin) of −61.06 dB at 13.28 GHz. Besides, it has a broad effective absorption bandwidth (EAB) of 6.5 GHz, with EAB >5.0 GHz covering a wide range of thickness. Such impressive results may provide experience for the application of Ti3C2Tx ceramics and 2D materials.  相似文献   

10.
Light-weight and flexible 2D MXene-based polymer materials with low dielectric loss and high dielectric constant have drawn great attention in the power systems and modern electronic field. A series of Ti3C2Tx/EMA composites were fabricated via simple solution casting followed by a compression molding method with various mass concentrations of Ti3C2Tx (0, 1, 3, 5, 8, 10, 12, and 15 wt%). Morphological and micro structural properties of the prepared composites were studied via X-ray diffraction (XRD) and field-emission scanning electron microscope (FESEM), where the distribution of Ti3C2Tx in the Ti3C2Tx/EMA composites was confirmed. Thermal behaviors were analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) investigations. The DSC analysis reveals that the % of crystallinity decreases from 11.06 with 1 wt% to 5.68 with 15 wt%, where Ti3C2Tx acts as an efficient nucleating agent. TGA data confirm the enhancement of the thermal stability of the composites upon increasing in Ti3C2Tx loading. The room temperature electrical and dielectric behavior of the studied composites were examined in the frequency range of 100 Hz–5 MHz. In this work, the 10 wt% of Ti3C2Tx loaded poly (ethylene-co-methyl acrylate) composite (EMA) showed higher dielectric permittivity (ε′ = 124.22) with lower dissipation loss (tan δ = 0.051) at 100 Hz among all weight percentages. The behavior of charge carriers in the prepared composites was studied by utilizing the impedance spectroscopy technique. The electrical parameters were calculated from the fitted Nyquist plots with a corresponding circuit model. I–V curves confirmed the conduction mechanisms of the composites. This beneficial enhancement in electrical properties recommends the composite can be utilized in flexible electronic storage devices.  相似文献   

11.
《Ceramics International》2021,47(18):25531-25540
Ti3C2Tx exhibits excellent electromagnetic (EM) shielding and electrochemical properties. However, the inherent re-stacking tendency and easy oxidation of Ti3C2Tx limit its further application. In this study, a multi-walled carbon nanotube/polyaniline composite (CNT/PANI, denoted as C–P) was introduced into Ti3C2Tx nanosheets to obtain a Ti3C2Tx–CNT/PANI composite (T@CP). Owing to the integrated effects of Ti3C2Tx and C–P, the contribution of absorption was significantly improved, which finally enhanced the EM shielding performance of T@CP. The highest total EM shielding effectiveness (SET) was close to 50 dB (49.8 dB), which was substantially higher than that of pure Ti3C2Tx (45.3 dB). Moreover, T@CP demonstrated outstanding supercapacitive performance. The specific capacitance of T@CP (2134.5 mF/cm2 at 2 mV/s) was considerably higher than that of pure Ti3C2Tx (414.3 mF/cm2 at 2 mV/s). These findings provide a new route for the development of high-efficiency Ti3C2Tx-based bifunctional EM shielding and electrochemical materials.  相似文献   

12.
《Ceramics International》2021,47(21):29995-30004
Novel and highly effective electromagnetic interference (EMI) shielding materials are desirable to attenuate unwanted electromagnetic radiation or interference produced by electrical communication devices. Here, functional Ti3C2Tx@Ni particles with a core@shell and sandwich like structure were fabricated using the facile electroless plating technique. The core@shell structured Ti3C2Tx@Ni consists of a Ti3C2Tx core and a Ni shell. In the core, thin Ni layers are sandwiched in between Ti3C2Tx flakes. EMI shielding effectiveness (SE) values of Ti3C2Tx@Ni/wax composites increased with increasing Ti3C2Tx@Ni content. The average EMI SE value of 60 wt% Ti3C2Tx@Ni/wax composite was 43.12 dB, increased by 73% as compared with 24.93 dB for the same content of pristine Ti3C2Tx in wax in the frequency range 2–18 GHz. An average EMI SE of 74.14 dB was achieved in the 80 wt% Ti3C2Tx@Ni/wax. The enhanced EMI shielding performance should be ascribed to the synergic effect of the absorption loss of the Ti3C2Tx core and the magnetic loss of the Ni shell and the inner Ni layers.  相似文献   

13.
Ti3C2Tx MXene has been reported to be a metallic two-dimensional (2D) material with high conductivity, whereas its photoluminescence (PL) mechanism is still under debate. Herein, we demonstrate that large Ti3C2Tx MXene flakes exhibit tunable PL under ambient conditions. The as-prepared Ti3C2Tx MXene flakes emit blue, yellow-green and red light under different excitation wavelengths. Their PL emission wavelengths redshift as the excitation wavelength changes from violet to red light. Surface modification of the MXenes can further tune the PL peak wavelength into the near infrared region. Using density function theory (DFT) calculations, this excitation wavelength-dependent PL can be correlated to TiO2 defects that exist on the surface of Ti3C2Tx. Our study expounds on the optical properties of Ti3C2Tx MXene and is helpful for comprehensively understanding this novel material.  相似文献   

14.
Ti3C2Tx is a promising intercalation-type electrode material for capacitive deionization (CDI). However, Ti3C2Tx, obtained from traditional synthesized Ti3AlC2, is with large particle size and undersized interlayer space, which can easily lead to the longer ion diffusion path, fewer adsorption sites, and higher ion diffusion barrier in CDI process. In this work, subsize and Na+ intercalated Ti3C2Tx (Na+-Ti3C2Tx-MS) was prepared by HF etching KCl-assisted molten-salt synthesized Ti3AlC2 and following NaOH treatment. The Na+-Ti3C2Tx-MS achieves a high electrosorption capacity of 14.8 mg/g and a high charge efficiency of 0.81 at the applied voltage of 1.2 V in 100 mg/L NaCl solution. Besides, the stable desalination performance of Na+-Ti3C2Tx-MS has been confirmed. The superior performance of Na+-Ti3C2Tx-MS can be attributed to the subsize particle and larger interlayer space. Both two factors can effectively increase ions adsorption sites, shorten diffusion path lengths, and reduce diffusion barriers in the CDI process.  相似文献   

15.
As one of the novel two-dimensional metal carbides, Ti3C2Tx has received intense attention for lithium-ion batteries. However, Ti3C2Tx has low intrinsic capacity due to the fact that the surface functionalization of F and OH blocks Li ion transport. Herein a novel “plane-line-plane” three-dimensional (3D) nanostructure is designed and created by introducing the carbon nanotubes (CNTs) and SnO2 nanoparticles to Ti3C2Tx via a simple hydrothermal method. Due to the capacitance contribution of SnO2 as well as the buffer role of CNTs, the as-fabricated sandwich-like CNTs@SnO2/Ti3C2Tx nanocomposite shows high lithium ion storage capabilities, excellent rate capability and superior cyclic stability. The galvanostatic electrochemical measurements indicate that the nanocomposite exhibits a superior capacity of 604.1 mAh g?1 at 0.05?A?g?1, which is higher than that of raw Ti3C2Tx (404.9 mAh g?1). Even at 3?A?g?1, it retains a stable capacity (91.7 mAh g?1). This capacity is almost 5.6 times higher than that of Ti3C2Tx (16.6 mAh g?1) and 58 times higher than that of SnO2/Ti3C2Tx (1.6 mAh g?1). Additionally, the capacity of CNTs@SnO2/Ti3C2Tx for the 50th cycle is 180.1 mAh g?1 at 0.5?A?g?1, also higher than that of Ti3C2Tx (117.2 mAh g?1) and SnO2/Ti3C2Tx (65.8 mAh g?1), respectively.  相似文献   

16.
《Ceramics International》2020,46(13):21482-21488
Two-dimensional transition metal carbide (MXene) is a promising electrode material for supercapacitors because of its excellent electrochemical properties. Here, we report a controllable and facile strategy to prepare a freestanding and flexible N-doped Ti3C2Tx (N–Ti3C2Tx) film electrode with a hydrothermal method using hydrazine hydrate (N2H4∙H2O) as a nitrogen source. At a scan rate of 2 mV s−1, the N–Ti3C2Tx film electrode exhibits a high specific capacitance of 340 F g−1 and no capacitance degradation after 10,000 cycles in 1 M H2SO4 electrolyte. These results show that the N–Ti3C2Tx film could be used as an outstanding electrode material for high-performance supercapacitors. The operation of hydrazine treatment provides a more practical and convenient experimental method for N-doping.  相似文献   

17.
《Ceramics International》2020,46(12):20306-20312
Although the antibacterial properties of MXene nanosheets containing Ti3C2Tx are known, their antifungal properties have not been well studied. Herein, we present for the first time a report on the antifungal properties of Ti3C2Tx MXene. The Ti3C2Tx MXene was obtained by first exfoliating MAX phase of Ti3AlC2 with concentrated hydrofluoric acid, then the Ti3C2Tx was intercalated and deliminated by ethanol treatment and ultrasonication process. The delaminated Ti3C2Tx MXene nanosheets (d-Ti3C2Tx) were characterized using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), X-ray diffraction spectroscopy (XRD), and Raman spectroscopy. It was found that Ti3C2Tx MXene was characterized by lamellar structure alternating with layers of Ti, Al and C. The EDX results revealed that the delaminated Ti3C2Tx MXene nanosheets were composed of Ti, C, Si, O, F, and a trace amount of Al. The XRD and Raman spectra further indicated the elimination of Al and the formation of two-dimensional Ti3C2Tx MXene nanosheets. The antifungal activity of the delaminated Ti3C2Tx MXene was determined against Trichoderma reesei using the modified agar disc method. Observation using inverted phase contrastmicroscopy revealed inhibited fungus growth with the absence of hyphae around the discs treated wtih MXene. The surrounding of the control groups without an inclusion of MXene was found with large number of hyphae and spores. In addition, the spores of the fungi treated with the samples containing d-Ti3C2Tx MXene nanosheets did not germinate even after 11 days of culture. The results demonstrated disruption to the hemispheric structural formation of fungi colony, inhibition of hyphae growth and cell damage for fungi grown on the d-Ti3C2Tx MXene nanosheets. These new findings suggest that d-Ti3C2Tx MXene nanosheets developed in this work could be a promising anti-fungi material.  相似文献   

18.
MXene modified by stearic acid (Ti3C2Tx-g-SA) is incorporated into poly(lactic acid) (PLA) matrix to prepare Ti3C2Tx-g-SA/PLA composites. The effects of Ti3C2Tx-g-SA to pure PLA are investigated, including crystallization, mechanical, and thermal properties. Fourier transform infrared spectroscopy and X-ray diffraction analyses confirm that Ti3C2Tx interlayer is successfully intercalated by SA, and the interlayer spacing of Ti3C2Tx is increased. Differential scanning calorimetry illustrates that the cold crystallization enthalpy (ΔHcc), melting enthalpy (ΔHm), and crystallinity (Xc) of Ti3C2Tx-g-SA/PLA composites are improved by the plasticization and heterogeneous nucleation effect of Ti3C2Tx-g-SA. Specially, the Ti3C2Tx-g-SA/PLA composites exhibit excellent mechanical properties at an appropriate content of the Ti3C2Tx-g-SA. Compared with pure PLA, the elongation at break of the Ti3C2Tx-g-SA/PLA composite is increased 5.9-fold (up to 131.6%) when only containing 0.5 wt % Ti3C2Tx-g-SA. Besides, the Ti3C2Tx-g-SA/PLA composites exhibit good thermal stability in the low loading (lower than 1 wt %) of Ti3C2Tx-g-SA. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48621.  相似文献   

19.
To prevent restacking of the Ti3C2Tx layers, the Ti3C2Tx-foam has been successfully synthesized through thermal treatment of Ti3C2Tx-film with the hydrazine monohydrate. The interconnected porous structure of Ti3C2Tx-foam could effectively reduce the restacking of the Ti3C2Tx sheets and shorten the diffusion path of ions and accelerate the intercalation/de-intercalation of ions. The Ti3C2Tx-foam-80 used as free-standing electrode achieves a high areal capacitance of 271.2 mF/cm2 (122.7?F/g) at a scan rate of 5?mV/s in 1?M KOH electrolyte. It also exhibited a high capability rate of 65.5% from 5?mV/s to 100?mV/s and good cycle life with 88.7% retention of its initial after 10,000 cycles at a scan rate of 50?mV/s.  相似文献   

20.
Most of the ancient buildings are made of inflammable wooden structures, which have serious potential safety hazards. Applying fire-retardant coating is one of the simplest and most effective means of fire prevention in ancient wooden buildings. In this work, we have demonstrated that the Ti3C2Tx transition metal carbide/carbonitride (MXene) was applied as the synergetic agent, waterborne epoxy resin as the film-forming agent, ammonium polyphosphate, dipentaerythritol, and melamine (P-C-N system) as the intumescent fire-retardant system to prepare Ti3C2Tx/epoxy intumescent fire-retardant coating (TEIFC). The results showed that MXene has significantly improved the fire-retardant performance of the coating. By incorporating 3 wt% Ti3C2Tx (TEIFC-3, with 62 wt% P-C-N system), the coating displayed UL-94 V-0 rating with the limiting oxygen index value of 38%. In addition, the combination of Ti3C2Tx and P-C-N system enhanced the Shore hardness of the coating to 95 SHD (TEIFC-3). Furthermore, TEIFC-3 presented high thermal stability with the THRI of 177.0°C and Tdmax of 380.5°C. This work provides a novel strategy for the design and preparation of intumescent fire-retardant coating, which will greatly broaden the industrial applications of MXene-based polymer composites in the field of fire prevention of ancient buildings.  相似文献   

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