JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Tiansheng Liu,Na Liu,Qingda An,Zuoyi Xiao,Shangru Zhai,Zhongcheng Li
The unique features of 2D layered structure, native defects and abundant functional groups provide special peculiarities for exploring Ti 3 C 2 T x MXenes in microwave absorption field. Nonetheless, both bad conductivity and poor impedance matching of Ti 3 C 2 T x MXenes lead to relatively poor EM absorption performance. Herein, by modifying Ti 3 C 2 T x MXenes with conductive PPy microspheres , a new core-shell like delaminated structure composites were fabricated for significant enhancement of absorption performance. It demonstrated that the obtained Ti 3 C 2 T x @PPy composites showed excellent microwave absorption performance due to synergistic effect between Ti 3 C 2 T x and PPy microspheres. The 10 wt% Ti 3 C 2 T x @PPy composites in wax matrix displayed a minimum reflection loss (RL) of −49.5 dB at 7.6 GHz with 3.6 mm in thickness, and the effective absorption bandwidth was 5.14 GHz from 6.44 to 11.58 GHz. The widest effective absorption bandwidth was 6.63 GHz from 8.55 to 15.18 GHz, the RL reached −42.6 dB in 12.4 GHz at only 2.7 mm matching thickness. More importantly, the composites can cover 4–18 GHz by simply adjusting matching thickness of 2–5.5 mm. The fantastic absorption performance could be ascribed to the unique properties of Ti 3 C 2 T x MXenes and heterojunction in Ti 3 C 2 T x @PPy, which might be a promising material in microwave absorption applied aspects.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2022
·
IF 4.654
Yuman Zhang,Xiaolin Zhu,Suya Sun,Qirui Guo,Meigui Xu,Guan Wu
The advanced design of heterostructured fibers with ordered transport channels and porous frameworks for high-speed ions/electrons kinetics is principally fundamental for high-performance fiber-based supercapacitors (FSCs). However, typically low energy-storage performances restrict their substantive applications due to a fibrous restacking phenomenon and poor interfacial charge transfer. Here, we develop an ordered core–shell fiber, wherein the porous zeolitic imidazolate framework-67 (ZIF-67) polyhedron shell is uniformly loaded on a highly conductive Ti3C2Tx core via a versatile microfluidic method. Due to the improved porous generation, ordered porous pathways, large exposed surface, and in situ interfacial electron transfer, the ZIF-67@Ti3C2Tx fiber displays excellent volumetric capacitance (972 F cm–3) and long-term cycling stability (90.8% capacitive retention after 20 000 cycles) in 1 M KOH electrolytes. Meanwhile, the flexible solid-state ZIF-67@Ti3C2Tx FSCs maintain a good capacitance, large bending/wearable stabilities, and steady temperature-dependent capability. Based on those significant electrochemical performances, the supercapacitors can impressively power various electrical devices [e.g., light-emitting diodes (LEDs), displays, electric fans, pinwheels, and rolling bells], which will guide the practical progress of miniaturized energy technologies and smart electronics.
研究领域:
材料科学
·
能源存储技术
·
纳米技术
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Xiaohui Sun,Xueying Zhao,Xuyang Zhang,Guohua Wu,Xianhui Rong,Xiangwei Wang
Ti3C2Tx MXene is a potential microwave absorption material due to its unique physical and chemical properties. However, the impedance mismatch of MXene results in low microwave absorption. In this work, 2D/2D MXene@TiO2 composites were synthesized via a simple hydrothermal oxidation method, TiO2 is derived in situ from MXene without adding any additional Ti precursors. TiO2 with low permittivity can effectively regulate the impedance matching and enhance loss mechanisms. The MXene@TiO2-6 h composite shows a reflection loss (RL) of −58.3 dB at 11.36 GHz with a thickness of 1.75 mm, and the maximum effective absorption bandwidth (EAB) is 4.08 GHz (13.92–18 GHz) at 1.26 mm. Furthermore, the 2D/2D composite can obtain efficient microwave absorption at different frequencies by adjusting the thickness; RL can reach −39.1 dB at 5.04 GHz with a thickness of 3.5 mm. The radar cross section (RCS) of MXene@TiO2-6 h is lower than −19 dB m2 at −60–60°, and the minimum RCS is −56 dB m2 at 15°. This work provides a valuable experience in developing microwave absorption materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2020
·
IF 6.444
Qianfan Zhou,Kunpeng Qian,Jianhui Fang,Miao Miao,Shaomei Cao,Xin Feng
With the mushrooming of smart electronic devices, ultrathin Ti 3 C 2 T x MXene based EMI shielding materials with long term durability have aroused much interest. Herein, 2D Ti 3 C 2 T x /g-C 3 N 4 heterojunction films were firstly assembled using cellulose nanofibrils (CNF) as green binder via a solution-based pressured-filtration process. The heterojunction film with Ti 3 C 2 T x /g-C 3 N 4 mass ratio of 5:1 (28.20 µm in thick) exhibited distinguished performance with EMI shielding effectiveness of 42.99 dB in X-band and high tensile strength of 23.85 MPa. Specially, the generation of photo-electrons from g-C 3 N 4 nanosheets reduced TiO 2 into lower valence states under 365 nm UV light-irritation, resulting in lower loss on electrical conductivity as well as EMI shielding performance compared to their unilluminated counterparts. The reduction on TiO 2 offered by the g-C 3 N 4 enables the heterojunction film to be considered as a promising alternative EMI shielding material for future potential applications, because it can run long time just need UV light modulation.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Kexuan Hu,Hehe Wang,Xiang Zhang,Hui Huang,Tai Qiu,Yang Wang,Chuanfang (John) Zhang,Limei Pan,Jian Yang
Light weight is one significant pursuit for microwave absorption (MA) materials. Generally, constructing foams with porous structure and low density as the absorber is one efficient way to reduce the absorber content and the quality of MA materials since the porous structure can effectively cause multiple reflections of electromagnetic waves and enhance the MA performance. Herein, we report a new and simple method for fabricating ultralight Ti 3 C 2 T x foams by hydrochloric acid induced self-assembly and freeze-drying, for which the pore structure and MA performance can be effectively regulated by pre-freezing temperature. The decrease of pre-freezing temperature from −20 °C to −196 °C results in a reduced pore size, more homogenous pore structure, a decreased electrical conductivity, a decreased dielectric constant and a significantly enhanced MA performance. 3.3 wt% Ti 3 C 2 T x foams was immersed into molten paraffin to prepare composites for the MA performance tests. Due to the synergy of multiple reflection, conductive loss and polarization relaxation, the Ti 3 C 2 T x foams pre-frozen at −196 °C shows the most superb and impressive MA performance, a minimum reflection loss (RL) of −50.6 dB at the thickness of 1.8 mm and an effective absorption bandwidth (EAB) of 4.2 GHz (13.8–17.6 GHz) at the thickness of 1.4 mm, and the EAB could be adjusted in a range of 11.9 GHz (6.1–18 GHz) by increasing the thickness from 1 mm to 3 mm. This is one of the most lightweight materials with excellent MA performance to our knowledge, which perfectly meet the combined pursuit of light weight, thin thickness, broad bandwidth and strong absorption. This work offers a simple strategy for constructing 3D porous Ti 3 C 2 T x -based foams facing the application such as MA, electromagnetic shielding, environmental governance, energy storage and sensors.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Kai Yang,Min Luo,Daotong Zhang,Chaozheng Liu,Zhao Li,Liangcai Wang,Weimin Chen,Xiaoyan Zhou
Porous carbon (PC) can effectively alleviate the typical self-stacking phenomenon of 2D MXene-based films as a spacer, and can easily customize their porous structure. Nevertheless, the contact between 3D PC and 2D MXene flakes is generally presented at a point-to-point form owing to the irregular shape of PC, leading to a low efficiency on electron delivery and stress concentration with a fragile characteristic in the resulting films. Herein, 1D carbon nanotube (CNT) was introduced to construct a highly conductive net structure, tightly anchoring PC on MXene flakes, thus ensuring fast electron delivery by increasing the contact area between MXene and PC. Additionally, the interwoven CNTs bridge the horizontal MXene flakes, making internal structure more integral, thereby enhancing the flexibility. Consequently, the Ti 3 C 2 T x (a typical MXene)/CNT/PC (TCP) film has an ability to bear a large scan rate of 1 V s −1 and shows a high areal specific capacitance of 364.8 mF cm −2 at 0.5 mA cm −2 which remains above 80% even at a high current density of 50 mA cm −2 . Furthermore, the fabricated flexible quasi-solid-state supercapacitor (SC) demonstrates a large areal energy density of 10.5 μ Wh cm −2 at 29.8 μ W cm −2 . This study provides a promising approach to overcome the poor flexibility of MXene/PC film without sacrificing the conductivity, meanwhile paving a way for the development of flexible SCs with large charge storage capacity and high rate capability.
研究领域:
材料科学
·
能源存储
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2021
·
IF 4.821
Mingchao Cao,Shiteng Liu,Shusheng Liu,Zhaogang Tong,Xijun Wang,Xinhua Xu
In this study, monolayer titanium carbide (Ti 3 C 2 T x ) material was prepared, then the modified ZnO and Ti 3 C 2 T x were self-assembled to obtain the MXene based composite material. Finally, ZnO/Ti 3 C 2 T x /Nafion/Au electrodes were prepared to construct a dopamine electrochemical sensor for detection of dopamine. SEM, XRD measurements and so on verified the synthesis of monolayer Ti 3 C 2 T x and preparation of the MXene based composite material. Utilizing Chronoamperometry (I-t), we found the electrodes displayed a linear dynamic range from 0.1 to 1200 μM with a limit of detection of 0.076 μM (S/N = 3). Meanwhile, the sensitivity of the sensor is 96nA/μM and in the prepared biological samples, the recoveries of the sensor were 97.8%∼102.2%. Finally, the electrochemical sensor showed a good reproducibility and stability.
研究领域:
材料科学
·
生物医学工程
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Bingbing Chen,Aihu Feng,Kun Liu,Jiao Wu,Yun Yu,Lixin Song
Ti 3 C 2 T x is a promising intercalation-type electrode material for capacitive deionization (CDI). However, Ti 3 C 2 T x , obtained from traditional synthesized Ti 3 AlC 2 , 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 Ti 3 C 2 T x (Na + -Ti 3 C 2 T x -MS) was prepared by HF etching KCl-assisted molten-salt synthesized Ti 3 AlC 2 and following NaOH treatment. The Na + -Ti 3 C 2 T x -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 + -Ti 3 C 2 T x -MS has been confirmed. The superior performance of Na + -Ti 3 C 2 T x -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.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Interfaces
·
2022
·Vol. 9
·期 24
·2201165
·
IF 6.389
Xiaohan Xu,La Li,Weijia Liu,Zhongming Chen,Di Chen,Guozhen Shen
Thermally chargeable supercapacitors (TCSCs) are emerging and promising devices that could convert thermal energy spontaneously existing in nature into electricity and then store energy for further utilization. Herein, this work reports on the freestanding 3D Ti 3 C 2 T x MXene-based TCSC, where lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), poly(ethylene oxide) (PEO), and polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) serve as gel electrolyte. Different from the semiconductor-based thermoelectric materials, the fabricated Ti 3 C 2 T x TCSC exhibits a high Seebeck coefficient of 78.4 mV K −1 . Moreover, when applying a temperature difference (ΔT) of 5.8 K between the cold and hot sides, the Ti 3 C 2 T x TCSC devices provide a stable high voltage of 400.6 mV. The charging/discharging cycles of the Ti 3 C 2 T x TCSC devices upon periodic Δ T of 3.3 and 5.8 K demonstrate their excellent stability. To realize the practical application, the four Ti 3 C 2 T x TCSCs devices connected in series are charged by supplying a Δ T of 5.8 K and used to power a digital timer, demonstrating the possibility and application of the TCSCs in self-powered integrated electronics.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Niandu Wu,Wenhua Zhao,Boye Zhou,Yizhang Wu,Wentao Hou,Wei Xu,Jun Du,Wei Zhong
Ti 3 C 2 T x (MXene) has intriguing application potential for supercapacitors. However, it usually suffers from self-accumulate and restack, resulting in the decrease of electrochemical active sites and low capacitance. Here, we demonstrated a 3D nitrogen-doped Ti 3 C 2 T x /rGO (NTG) foam which was synthesized through the multistep of gelation assisted with urea, freeze-drying, and thermal treatment processes. The decomposition of urea can not only change the morphology, bringing out more open marco- and microporous structures, but also improve the conductivity due to the nitrogen doping in the matrix. The 3D porous architecture can expose more electrochemical active sites, and thus accelerate the transport/diffusion of electrolyte ions. Consequently, the NTG foam possesses a high specific capacitance of 463 F g −1 , good rate performance, and outstanding cycling stability (90.8% retention after 10 000 cycles) in H 2 SO 4 electrolyte, showing enhanced performance of supercapacitors in comparison with pure Ti 3 C 2 T x and Ti 3 C 2 T x /rGO electrode.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Xiaoqing Bin,Yapeng Tian,Yangyang Luo,Minhao Sheng,Yijia Luo,Maomao Ju,Wenxiu Que
In order to obtain high-performance flexible electrodes for supercapacitors, the nitrogen-doped delaminated-Ti 3 C 2 T x (N-d-Ti 3 C 2 T x ) decorated with MoO x nanoparticles (N-d-Ti 3 C 2 T x /MoO x ) films are prepared by a one-step solvothermal method. The N-d-Ti 3 C 2 T x nanosheets with high conductivity can facilitate electron transfer during the charge and discharge process, and the MoO x nanoparticles can contribute to high pseudocapacitance. Hence, their combination is expected to not only inhibit N-d-Ti 3 C 2 T x nanosheets from re-stacking, but also enhance the specific capacity of the whole electrode. Here, benefiting from the synergistic effect of the two components, the obtained optimal flexible and free-standing N-d-Ti 3 C 2 T x /MoO x film electrode delivers an ultrahigh capacity of 341.0 C g −1 (920.6 C cm −3 , 487.1 F g −1 , 1315.2 F cm −3 ) at the scan rate of 2 mV s −1 , and shows superior capacity retention of 99.2% after 11000 cycles at the current density of 5 A g −1 . Moreover, the flexible and free-standing N-d-Ti 3 C 2 T x /MoO x film electrode is also beneficial to promote the development of flexible supercapacitors.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 8
·3414-3422
·
IF 2.7
Di Wang,Deyang Zhang,Binhe Feng,Jinbing Cheng,Zuxue Bai,Zhaorui Wang,Jin Chang,Paul K. Chu,Yang Lu,Yongsong Luo
MXenes have gained significant recognition due to their outstanding electrical conductivity, abundant surface functional groups, and distinctive two-dimensional layered structure. However, restacking of nanoflakes hinders the electrochemical performance of Ti3C2Tx-based supercapacitors. Herein, a Ti3C2Tx/VN composite is fabricated using a one-step in situ nitriding method. The presence of VN within the Ti3C2Tx nanoflakes results in an increased interlayer spacing, providing additional electrochemically active sites for charge storage. In addition, the Ti3C2Tx nanosheets form a continuous metallic skeleton that suppresses the formation of soluble salts from VN during charging and discharging resulting in better cycling stability. As the negative electrode in supercapacitors, Ti3C2Tx/VN demonstrates an outstanding specific capacity of 382.1 F g−1 at a current density of 1 A g−1 and exceptional cycling endurance, retaining 93.5% of its capacity after 5000 cycles. An asymmetric supercapacitor comprising Co3O4 and Ti3C2Tx/VN as the positive and negative electrodes, respectively, shows high energy and power densities of 69.1 W h kg−1 (1 A g−1) and 7.6 kW kg−1 (8 A g−1). The results reveal a promising strategy to design composite anodes with high energy and power densities for supercapacitors.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）