COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Yefeng Feng,Hongrong Qiu,Bingshuang Mao,Maolin Bo,Qihuang Deng
High dielectric constant and breakdown strength of composite dielectrics are key for high energy density in capacitors. However, high dielectric constant is frequently accompanied by rather low breakdown strength. To obtain high dielectric constant and breakdown strength, in this work, polymer-based ternary composites bearing V 2 C MXene-Cu 2 O hybrid filler have been prepared. First, V 2 C and V 2 C-Cu 2 O fillers were synthesized. Then, binary polymer/V 2 C and ternary polymer/V 2 C-Cu 2 O composite films were fabricated. Via measurements, significantly optimized electric traits were realized in ternary composites compared with binary ones. In ternary system , higher dielectric constant was attributed to high-polarity V 2 C/Cu 2 O interface-phase, notably reduced dielectric loss low polymer/V 2 C interface leakage conductance, and greatly improved breakdown strength low total leakage current . Finally, V 2 C/Cu 2 O interfacial effect was disclosed using density functional theory (DFT) calculations. Electronic migration and stable bonding at interface were rationalized. Ternary composite with 7 wt% filler showed a high dielectric constant of ~55 and low dielectric loss of ~0.085 at 100 Hz as well as high breakdown strength of ~332 MV m −1 . In novelty, V 2 C/Cu 2 O interface-phase containing quantum-sized high-polarity micro-regions has been proposed to contribute to high dielectric constant of ternary system. This research might enable preparation of advanced composite dielectric materials.
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Yao Wang,Yijia Liang,Xingjun Ma,Yanling Dong,Matthana Klakong,Anbin Wang,Mengle Chen,Tianyu Fan,Xiaohong Xu,Peng Xiao,Wei Ding
Frequent or excessive use of synthetic pesticides can easily lead to pollution of soil and groundwater in management of soil-borne diseases. An environmental-friendly vanadium carbide MXene nanosheets (V 2 C-NSs) have been widely studied in the field of nanomedicine and biomaterials. However, few studies have shown has direct effects of V 2 C-NSs on crop protection and induces plant resistance to disease. In this study, V 2 C-NSs were first prepared by artificial synthesis and characterized, and the resulting material displayed an excellent Tyndall effect. The ability of V 2 C-NSs to promote plant growth and biosafety and its molecular mechanism of inducing plant resistance to Ralstonia solanacearum ( R. solanacearum ) were investigated. The results showed that V 2 C-NSs could increase plant fresh (or dry) weight, promote ROS accumulation, activate plant defense enzymes, and upregulate ethylene (ET) and jasmonic acid (JA) synthesis as well as the expression of ET/JA-responsive genes. Interestingly, the MAPK signaling pathway, biosynthesis of henylpropanoid and flavonoid were also activated, but the salicylic acid biosynthetic pathway was deactivated. Thus, V 2 C-NSs likely induced plant resistance to R. solanacearum via the ET/JA pathway. Furthermore, foliar application of V 2 C-NSs could delay occurrence of tobacco bacterial wilt, while the control efficiency reached 65.52 % nine days post-inoculation (dpi), followed by 57.00 % and 52.99 % at 11 dpi and 13 dpi, respectively, which were significantly greater than the control benzothiadiazole (BTH). Moreover, the biosafety of V 2 C-NSs was evaluated using tobacco seeds (Yunyan87), bacteria and earthworms. This study suggests that V 2 C-NSs can potentially be used as an environmental-friendly plant resistance inducer for controlling bacterial wilt diseases in sustainable crop protection.
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2020
·
IF 7.098
Baojun Liu,Lanlan Yu,Fei Yu,Jie Ma
Capacitive desalination (CDI) has aroused much attention due to its advantages of low energy consumption and environmental compatibility. However, typical CDI processes display limited efficiency. In this work, one-dimensional V 2 O 5 with nanocuboid structure was prepared with MXenes(V 2 C) precursor for the first time, which has high adsorption capacity, structure stability and fast ion diffusion ability. The as-synthesized V 2 O 5 electrode achieved a salt adsorption capacity(SAC) of 55.2 mg NaCl g −1 V 2 O 5 under optimized conditions with a constant current density of 30 mA g −1 , a voltage range from −0.6 to 1.2 V, and an initial solution of 500 mg L −1 NaCl. Furthermore, from the comprehensive analysis of mechanism, due to the high conductivity and low charge transfer resistance of V 2 O 5 electrode, it reduces the energy loss of the resistance during desalination. A particularly low energy consumption of 0.27 kWh kg −1 -NaCl is reached when the operation is carried out successfully at low voltage range, indicating the advantages of energy saving and high efficiency. Therefore, V 2 O 5 is an attractive and promising electrode material, which exhibits the potential of pseudocapacitive materials with certain structure for practical CDI application in future and inspires us to have a deep insight into the effect of morphology on the properties.
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 9
·期 3
·1051-1061
·
IF 7.059
Qihuang Deng,Binghe Chen,Maolin Bo,Yefeng Feng,Yuehao Huang,Junquan Zhou
A high dielectric constant and electric breakdown strength are desired in high-energy-density polymer/ceramic composites. Ultrahigh interface leakage conduction between polymer and carbon nanotubes (CNTs) hinders the development of CNT-filled composite dielectrics. In this work, composite dielectrics bearing V2C MXene-CNT hybrid-particles were fabricated. Environment-friendly polyvinyl alcohol (PVA) was employed as the matrix. Interface polarization between PVA and ceramics improved the dielectric constant of composites. A switchboard micro-structure was obtained in the hybrid-ceramic consisting of layered V2C and thread-like single-walled carbon nanotubes (SWCNTs). This micro-structure led to adsorption-migration of fluorine from V2C to CNTs, triggering Coulomb-blockade zones at CNT surfaces supported by first-principles molecular-dynamics calculations. Interface leakage conduction between CNTs and PVA was depressed by quick-slow-quick (QSQ) electron transmission of CNTs. Compared to PVA/CNT composites, PVA/V2C–CNT composites exhibited a favorable high dielectric constant, strongly depressed low dielectric loss and conductivity, and elevated high breakdown strength. The ternary composite with 5 wt% hybrid-ceramic showed a dielectric constant of ∼232 (122 times that of PVA) and a dielectric loss of ∼0.2 (1.4 times that of PVA) at 100 Hz, as well as a breakdown strength of ∼35 MV m−1 (60% of that of PVA). A balance of high dielectric constant and breakdown strength was achieved in the ternary system. This work might enable large-scale preparation of high-performance composite dielectrics.
✓ 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）