Science Bulletin
·
2022
·
IF 20.577
Pengxiang Zhang,Yushui Fu,Xin Zhang,Xihua Zhang,Bao-Wen Li,Ce-Wen Nan
Chemically exfoliated nanosheets have exhibited great potential for applications in various electronic devices. Solution-based processing strategies such as inkjet printing provide a low-cost, environmentally friendly, and scalable route for the fabrication of flexible devices based on functional inks of two-dimensional nanosheets. In this study, chemically exfoliated high- k perovskite nanosheets (i.e., Ca 2 Nb 3 O 10 and Ca 2 NaNb 4 O 13 ) are well dispersed in appropriate solvents to prepare printable inks, and then, a series of microcapacitors with Ag and graphene electrodes are printed. The resulting microcapacitors, Ag/Ca 2 Nb 3 O 10 /Ag, graphene/Ca 2 Nb 3 O 10 /graphene, and graphene/Ca 2 NaNb 4 O 13 /graphene, demonstrate high capacitance densities of 20, 80, and 150 nF/cm 2 and high dielectric constants of 26, 110, and 200, respectively. Such dielectric enhancement in the microcapacitors with graphene electrodes is possibly attributed to the dielectric/graphene interface. In addition, these microcapacitors also exhibit good insulating performance with a moderate electrical breakdown strength of approximately 1 MV/cm, excellent flexibility, and thermal stability up to 200 ℃. This work demonstrates the potential of high- k perovskite nanosheets for additive manufacturing of flexible high-performance dielectric capacitors.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Pengxiang Zhang,Binbin Zhang,Feng Dang,Cewen Nan,Bao-Wen Li
Inkjet printing of two-dimensional perovskite nanosheets offers a promising avenue for manufacturing high-performance microcapacitors. However, optimizing and improving the dielectric performance of these printed microcapacitors remains a significant challenge. Here, Bi-doped Sr2Nb3O10 perovskite nanosheets are engineered, dispersed in an environmentally friendly water/ethanol mixed solvent, and meticulously assembled with Ag and graphene into microcapacitors by inkjet printing technology. Enhanced dielectric performance is achieved by controlling the Bi doping content and fine-tuning the electrode/dielectric interface. A high capacitance density of approximately 193 nF/cm2 and an impressive dielectric constant reaching up to 250 are demonstrated in inkjet-printed graphene/Sr1.7Bi0.3Nb3O10/graphene microcapacitors. Such microcapacitors also feature good insulating performance with a moderate electrical breakdown strength of ~1 MV/cm, robust flexibility, strong electric field stability within 40 V, excellent stability up to 200 °C, and moderate reproducibility of ~76.7%. Additionally, these devices exhibit a high sensitivity to chemical solvents of different polarities, which can significantly enhance the dielectric performance of these printed microcapacitors. Our work may provide an effective route to improve the dielectric performance of inkjet-printed microcapacitors based on 2D dielectric nanosheets.
研究领域:
材料科学
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 25
·12735-12743
·
IF 11.301
Kaiqiang Wang,Yanfei Liu,Jinjin Li,Jianfeng Li
Drawing potential has recently been observed in monolayer graphene that can generate electricity upon interaction with water; however, it remains a challenge to generate drawing potential in lower-cost and more stable layered materials. In this study, we used an electro-fluidic assembly method to fabricate a smooth reduced graphene oxide (rGO) film. A voltage in the millivolt magnitude was generated by controlling the movement of an ionic solution droplet over this rGO film, and the type and concentration of the ionic solution and the volume and sliding velocity of the droplet could directly influence the voltage amplitude. The direct observation of electrical double repulsive force between the rGO film and a silica probe confirms the existence of an electric double layer (EDL) on the rGO film, which leads to the formation of a micro-capacitor at the droplet/rGO film interface. Electricity was generated due to the transfer of electrons along the rGO film through the adsorption and desorption of cations in the solution, which is determined by the surface charge density on the rGO film. Because the rGO film is flexible and can be easily transferred onto a soft substrate, it has promising applications in wearable energy-harvesting devices and self-powered micro-electromechanical systems.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
Energy Storage Materials
·
2021
·
IF 17.789
Miaoxin Zhang,Ruijun Bai,Shane King,Fuxing Yin,Huifen Peng,Gongkai Wang
Planar micro-supercapacitors (MSCs) with high energy/power densities and long cycle life are expected to expedite the development of the future wearable miniaturized electronics. However, its low energy density issue always falls short in ever-increasing demands of specific energy consumption. Herein, a dual active and kinetically inter-promoting Li 3 VO 4 (LVO)/graphene composite is designed as the anode for high energy density lithium ion micro capacitors (LIMCs). The LVO nanoparticles are evenly confined on graphene nanosheets through an atomic layer pre-deposition (ALD) technique, which substantially disperses the nucleation site and impedes the coarse grain growth in the successive solid-state formation of LVO. The much-promoted reaction kinetics of LVO and graphene substrate with sufficient diffusion space in the interdigital electrodes of LIMCs synergistically boost the three-dimensional and efficiently lithium ion storage behavior. The LVO/graphene exhibits extraordinary rate capability (98.5 mAh g −1 at 40 A g −1 (100 C)) and long-term stability. All the current collectors and asymmetric interdigital electrodes are spray printed, opening a facile and delicate technique for a large-scale production of LIMCs. The LIMCs deliver a superior volumetric energy density of 51.4 mWh cm −3 , excellent flexible and cyclic stability, demonstrating a great potential for the future miniaturized, flexible, and high-performance energy storage devices.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2018
·
IF 2.906
Qilong Zhang,Yongchang Jiang,Enjie Yu,Hui Yang
Core-shell structured BaTiO 3 @polyaniline (BT@PANI) nanoparticles were synthesized via surface hydroxylation and in-situ polymerization method and were embedded into Poly(vinylidene fluoride- co -hexafluoropropylene) [P(VDF-HFP)] matrix. The dielectric performance as well as thermal behavior of BT@PANI/P(VDF-HFP) nanocomposite films are investigated. The crystallinity increases with increasing the BT@PANI content. Compared with BT particles, the BT@PANI core-shell nanoparticles exhibit notable improvement on dielectric properties . Typically, with a filler content of 20 vol% BT@PANI, the dielectric constant of BT@PANI/P(VDF-HFP) composite film reaches 99.1 at 1 kHz, which is 6.2 times larger than that of 20 vol% BT (16.1) and 9.6 times larger than pristine P(VDF-HFP) (10.3). Enhanced permittivity is generated from the interfacial polarization and the microcapacitor effect provided by the core-shell nanoparticles. Moreover, nanocomposite film maintains a low dielectric loss of 0.21 at 1 kHz. This research offers a solution for fabricating dielectric composite with large dielectric constant and low dielectric loss, which could be beneficial for the improvement of advanced electronic devices.
研究领域:
材料科学
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电气工程
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Ruijun Bai,Miaoxin Zhang,Xin Zhang,Shijing Zhao,Weifeng Chen,Ning Chen,Puguang Ji,Mirtemir Sh Kurbanov,Hua Wang,Huiyang Gou,Gongkai Wang
Transparent flexible supercapacitors (TFSCs) are a tantalizing power supplier for future transparent flexible electronics. However, their energy density is far behind a practical level while maintaining high transparency. We report here a transparent flexible potassium-ion microcapacitor, and its high energy density (15.5 μWh cm–2) roots in the battery-supercapacitor hybrid storage mechanism and much enlarged working voltage (3 V), outperforming the state-of-the-art TFSC, which is generally based on an aqueous electrolyte and an asymmetric pseudocapacitive mechanism. From an electrode material perspective, a multidimensional topotactic host composite anode is designed in which the component not only performs energy storage by synchronous and reversible uptake of potassium ions and electrons into its host structure, but also mutually compensates individual weakness in functional and structural aspects, efficiently constructing a three-dimensional potassium-ion diffusion and electron transport system. This conceptual exhibition provides design principles at material and device levels for high-performance TFSCs.
研究领域:
材料科学
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能源存储技术
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Yu Zeng,Chenhan Xiong,Wang Li,Shipeng Rao,Guoping Du,Zhaoyang Fan,Nan Chen
MXenes are attracting great interest for their excellent electrical and mechanical properties . High dielectric constants have been achieved in polymer-based nanocomposites with MXenes as fillers, but these materials suffer from large dielectric losses. In this work, Ti 3 C 2 T x MXene/silicone rubber (SR) nanocomposites were prepared because of the low dielectric loss of SR. The effects of Ti 3 C 2 T x MXene nanosheets on the thermal stability, dielectric and mechanical performance of the nanocomposites were investigated. A dielectric constant of 6.2 accompanied by an extremely low dielectric loss of 0.001 at 10 3 Hz frequency was obtained in the nanocomposites when 1.2 wt% Ti 3 C 2 T x MXene was loaded. The enhanced dielectric properties are mainly attributed to the Maxwell-Wagner-Sillars effect and the microcapacitor model. Moreover, the thermal stability of the nanocomposites can reach 450 °C. Tensile strength of 430 kPa, elongation at break of 341% and reduced elastic module of 402 kPa were also obtained in the nanocomposite with 2 wt% Ti 3 C 2 T x MXene. This work provides a method for fabricating polymer-based nanocomposites with excellent dielectric properties under low filling content, which is crucial for modern electronic applications.
研究领域:
材料科学
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电气工程
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Electronic Materials
·
2022
·
IF 4.494
Shuimiao Xia,Kuan Chen,Kelan Yan,Liming Shen,Meiyu Zhang,Zhicheng Shi,Runhua Fan
Polymer dielectric composites are extensively used in modern electronic devices because of their extremely high power density. However, unfavorable coupling between breakdown strength and dielectric permittivity can make achieving high energy density a challenge. In this study, reduced graphene oxide @ barium titanate (RGO@BTO) hybrid nanosheets have been fabricated and utilized as fillers in the design of RGO@BTO/P(VDF-HFP) single-layer films. An increase in permittivity to 24.8@10 kHz, i.e., equivalent to 253% of the P(VDF-HFP) (∼9.8@10 kHz) matrix, has been achieved with only 1 wt % RGO@BTO nanofillers due to the formation of microcapacitors. Furthermore, the RGO@BTO/P(VDF-HFP) film is hot-pressed with a PEI film and a P(VDF-HFP) film, forming a trilayer structure. Consequently, this trilayer film displays a high breakdown strength of 478 kV/mm, a high energy density of 8.25 J/cm3, and a satisfactory efficiency of 64.3%. Thus, this study provides an efficient route for designing polymer composites that combine high energy density with high permittivity.
研究领域:
材料科学
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电气工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Macromolecular Science Part B-Physics
·
2023
·
IF 1.4
Suyue Li,Shiting Wang,Wenzhong Ma,Haicun Yang,Zheng Cao,Chunlin Liu,Haimu Ye
The increased micro-capacitance of a poly (vinylidene fluoride) (PVDF) matrix can effectively improve the piezoelectric properties of the composite material. This work used chemically modified carbon nanotubes (CNTs) as the main reinforcement material. Atom transfer radical polymerization (ATRP) was used to graft polyionic liquids (PILs) with different hydrophilic anions to the CNTs’ surfaces. Solution casting and compressive melt molding were used to prepare the PVDF-composite piezoelectric films. Micro-capacitance formed by the PIL grafted CNTs dispersed well in the PVDF matrix, and their effects on the crystalline form and piezoelectric properties were studied. The hydrophobic hexafluorophosphate anion (-PF6-) can significantly improve the CNTs dispersion and enhance the micro-capacitance formation in the PVDF matrix. During solution crystallization, the synergistic effect of CNTs and PIL on the PVDF and the solvent effect made the content of β phase of PVDF/CNTs@PIL-PF6 film reach 80.2%, resulting in a high dielectric constant of 188 and a piezoelectric coefficient of 36. In the process of melt crystallization, due to shear stretching and extrusion, the CNTs@PIL-PF6 had an obvious nucleation effect on the polar crystalline phase of PVDF, with a β phase content up to 99.3%, leading to the higher dielectric constant of 530 and the piezoelectric coefficient of 31. The current discovery provides a development direction for smart piezoelectric polymer matrix composites, which have great potential in preparing piezoelectric energy storage materials.
研究领域:
材料科学
·
高分子科学
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纳米技术
·
电气工程
·
传感器技术
✓ 已验证
DOI
高影响因子
POLYMER
·
2019
·
IF 3.771
Jing Shao,Jing-Wen Wang,Da-Nian Liu,Lei Wei,Sen-Qiang Wu,Hua Ren
A high permittivity acrylic resin (AE)-based percolative composite with two-dimensional (2D) MXene nanosheets as the conducting fillers was fabricated. The Ti 3 C 2 T x MXene nanosheets were delaminated (referred to d-Ti 3 C 2 T x ) and then modified with polypyrrole (PPy). The d-Ti 3 C 2 T x /AE and PPy- d -Ti 3 C 2 T x /AE composite films with different filler loadings were obtained with the solution casting method. The dielectric constants of 6.36 vol %d-Ti 3 C 2 T x /AE and 5.98 vol %PPy- d -Ti 3 C 2 T x /AE are 493 and 265 at 10 2 Hz, respectively, approximately 140 and 75 times of pure AE (3.5). Meanwhile, the dielectric loss of PPy- d -Ti 3 C 2 T x /AE composite maintains at a relative low level (0.23 at 10 3 Hz) when the volume fraction of PPy- d -Ti 3 C 2 T x gets close to the percolation threshold ( f c = 6.39). The large enhancement in dielectric constant of composite is closely relevant to the microcapacitor effect and the free charge accumulation caused by the formation of interfaces between the conducting fillers and polymer matrix .
研究领域:
材料科学
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电气工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2018
·Vol. 6
·期 9
·2370-2378
·
IF 5.976
Yang Liu,Cheng Zhang,Benyuan Huang,Xu Wang,Yulong Li,Zaoming Wang,Wenchuan Lai,Xiaojiao Zhang,Xiangyang Liu
This paper presents a novel skin–core structured multiwalled carbon nanotube (MWCNTs) nanofiller to enhance the dielectric performance of epoxy resin through selective fluorination of the outer shell of the MWCNTs. The outer fluorinated shells not only guarantee good dispersibility of the fluorinated MWCNTs (F-MWCNTs) in epoxy, but also prevent the direct contact of the conductive inner tubes. As a result, the inner tubes in adjacent F-MWCNTs can form abundant microcapacitors, leading to an obvious improvement of the dielectric constant of the epoxy resin with low dielectric loss. When the filler content is 8 wt%, the dielectric constant of the F-MWCNTs/epoxy composite varies from 57 at 100 Hz to 44.9 at 1 MHz, about 11.9 times and 10.8 times that of neat epoxy resin, respectively. Simultaneously, the dielectric loss maintains low values of 0.043 at 100 Hz and 0.036 at 1 MHz, respectively. The broadband high-κ and low dielectric loss demonstrate the frequency-stable dielectric behavior of the F-MWCNTs/epoxy composites, which is attributed to the suppression of the space charge polarization induced by the grafting of the strongly electronegative element fluorine onto the outer shell. We believe that the convenient preparation process and special structure will provide a new design for fabricating broadband high-κ dielectric materials with low dielectric loss.
研究领域:
材料科学
·
电气工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
POLYMER TESTING
·
2022
·
IF 4.931
Zhaoxia Luo,Liqun Zhang,Yongri Liang,Shipeng Wen,Li Liu
To achieve high deformation under a low electric field intensity is still a big challenge for the dielectric elastomers (DE) potentially used in artificial electronic skin and artificial muscles. Herein, poly-dopamine (PDA) modified 1D barium titanate (BT@PDA) nanofibers and 2D MXene nanosheets with high aspect ratio and large dipole moment were fabricated, and introduced into TPU elastomers. Results showed that the interfacial polarization and micro-capacitor structure formed by MXene sheets lead to the high dielectric constant, and high dielectric loss of MXene/TPU composites with low modulus. The interfacial polarization caused by BT@PDA nanofibers resulting in high dielectric constant and low dielectric loss of BT@PDA/TPU composites with high modulus. Combing the advantages of the two fillers, the MXene/BT@PDA/TPU composites showed high dielectric constant, low dielectric loss, low modulus. The electrical sensitivity factor of 0.5 wt% MXene/5 wt% BT@PDA/TPU composite (11.38) was much higher than the sum of that of 0.5 wt% MXene/TPU (1.73) and 5 wt% BT@PDA/TPU (4.35) composites at a low filler content, showing the 0.5 wt% MXene/5 wt% BT@PDA/TPU dielectric composite had a large deformation under a low electric field. This work can provide an effect strategy to design DE nanocomposites with good deformation performance.
研究领域:
材料科学
·
纳米技术
·
电气工程
✓ 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）