Polymers
·
2022
·Vol. 14
·期 13
·2631
·
IF 4.967
Boyan Zhao,Yaxiong Tan,Feipeng Wang,Li Yang,Nuo Cheng
Insulating oil is a pivotal component of power transformers, but it suffers from aging byproducts during service operation. The aging byproducts from the degradation of oil insulation tend to induce insulation failure, which poses a significant threat to the security of the power grid. Therefore, the regeneration of insulating oil is required to prolong the useful life of insulating oil and hence be of economic and ecological interests. Typical in-use oil regeneration routes employ multi-step procedures. In this work, a one-step regeneration method using a PVDF/BaTiO3composite membrane is proposed. BaTiO3endows the composite membrane with improved hydrophobicity and an electret state. The regeneration performance of the PVDF/BaTiO3nanofiber membrane was assessed by considering the acid value, moisture content, dielectric loss factor tan δ, and the AC breakdown voltage of the refreshed oil. The test results showed that the filtration efficiencies toward formic acid and moisture were up to 77.5% and 60.6%, respectively. Moreover, the dielectric loss factor tan δ of the refreshed oil decreased evidently at a power frequency, and the AC breakdown voltage rose from 23.7 kV to 38.9 kV. This suggests that the PVDF/BaTiO3composite membrane may be employed efficiently, and it minimizes aging byproducts via the one-step filtration.Keywords:electret;insulating oil regeneration;PVDF/BaTiO3nanofiber;electric field
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
PubMed
高影响因子
Nano Energy
·
2019
·
IF 15.548
Nan Ma,Ya Yang
Research of photovoltaic effect has been increased based on ferroelectric materials , generating a series of important discoveries. However, the conventional ferroelectric ceramics usually have low photocurrent values. How to increase the photocurrent of ceramics becomes an important issue to push forward the practical application of these devices. Here, we report the intrinsic properties about the temperature dependence of photocurrent and its relationship with the ferroelectric polarization. The photocurrent of BaTiO 3 ceramics strongly depends on the temperature, which can achieve an enhancement of 121.9～179.6% at low temperature (80–240 K) as compared with that at room temperature. The enhancement of photocurrent is associated with ferro-pyro-phototronic effect, evidencing by the enhanced ferroelectric polarization and the activation of shallow trap levels at low temperature, which can be used for detecting 405 nm light under low temperature. This research provides a potential approach to boost the photocurrent of ferroelectric ceramics and enable the development of a wide range of optoelectronic devices.
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2014
·Vol. 16
·期 26
·13078-13085
·
IF 4.198
Dan Xu,Lidong Wang,Weili Li,Wei Wang,Yafei Hou,Wenping Cao,Yu Feng,Weidong Fei
BaTiO3–xAlN (BT–xAlN) composite ceramics were prepared by conventional solid state reaction sintering. The effects of the AlN content on the crystalline structures, densities, and electrical and mechanical properties of the BT ceramics were investigated. The BT–1.5%AlN ceramic exhibits a good piezoelectric constant of 305 pC N−1 and an improved Vickers hardness of 5.9 GPa. The enhanced piezoelectricity originates from interactions between defect dipoles and spontaneous polarization inside the domains due to the occurrence of local symmetry, caused by the preferential distribution of the Al3+–N3− pairs vertical to the c axis. The hardening of the material is attributed to the improved density, and particle and grain boundary strengthening. Our work indicates that if a suitable doping ion pair is designed, lead-free ceramic systems prepared from ordinary raw materials by a conventional sintering method have a high probability of exhibiting good piezoelectric and mechanical properties simultaneously.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Energy & Environmental Science
·
2024
·Vol. 17
·期 11
·3797-3806
·
IF 32.4
Shaoke Guo,Shendong Tan,Jiabin Ma,Likun Chen,Ke Yang,Qiannan Zhu,Yuetao Ma,Peiran Shi,Yinping Wei,Xufei An,Qingkang Ren,Yanfei Huang,Yingman Zhu,Ye Cheng,Wei Lv,Tingzheng Hou,Ming Liu,Yan-Bing He,Quan-Hong Yang,Feiyu Kang
In composite solid-state electrolytes, functional fillers with ferroelectric properties have demonstrated their ability to prompt the dissociation of lithium salt (LiFSI), thereby significantly enhancing ionic conductivity. However, the underlying mechanism has been challenging to fully comprehend, which hinders further improvement in electrolyte performance. Herein, we elucidate the dissociation mechanism of LiFSI induced by the ferroelectric fillers of BaTiO3. We find that the dipole's direction of tetragonal-BaTiO3 (T-BTO) can slightly deflect under an external electric field of a battery to enhance the polarization. The {001} planes of T-BTO, aligned along the polarization direction, exhibit a more pronounced ability to dissociate lithium salt and accumulate anions owing to the formation of surface-absorbed FSI− by binding between the O of FSI− and the Ti of T-BTO. Moreover, T-BTO3−x fillers with enhanced spontaneous polarization by oxygen vacancy defects can further amplify these effects, leading to an increased proportion of free Li+ from 19% to 72%. The ionic conductivity of T-BTO3−x–poly(vinylidene fluoride) composite electrolyte can reach a value as high as 8.4 × 10−4 S cm−1 at 25 °C. This work reveals the dissociation mechanism of lithium salt due to the introduction of ferroelectric fillers and highlights its great promise for developing practical solid-state composite electrolytes.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Pengpeng Xu,Junyi Yu,Chaofan Li,Suibin Luo,Shanming Ke,Yangbo Zhou,Shuhui Yu,Rong Sun
Flexible polymer composites with high dielectric constants and low dielectric losses at high frequencies are highly desired in microwave and RF applications. However, a high dielectric constant is often obtained at the expense of flexibility because a high loading of filler is needed. In this work, we synthesize a core-shell structured 1D filler by coating high-dielectric-constant PbTiO 3 onto the surface of low-thermal-expansion-coefficient SiC nanofibers , which are then incorporated into the epoxy matrix together with BaTiO 3 nanoparticles to form the multi-phase BaTiO 3 /SiC@PbTiO 3 /epoxy composite film . A high dielectric constant (35 at 100 Hz and 20 at 5 GHz) and a low dielectric loss (0.023 at 100 Hz and 0.13 at 5 GHz) are achieved as the filling content of SiC@PbTiO 3 and BaTiO 3 is 5.24 wt% and 80 wt%, respectively. Prediction models of the effective dielectric constant of polymer-based composites reveal that a continuous polarization network is constructed in the composites owing to the physical contact between BaTiO 3 and PbTiO 3 . The construction of the multi-phase filler provides a feasible way to effectively adjust and improve the dielectric properties of polymer-based composite films.
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
ADVANCED FUNCTIONAL MATERIALS
·
2019
·Vol. 29
·期 51
·1907919
·
IF 15.621
Jianhua Yan,Yuhui Han,Shuhui Xia,Xiao Wang,Yuanyuan Zhang,Jianyong Yu,Bin Ding
BaTiO 3 crystals are attractive materials due to their high dielectric properties, but they are brittle and inelastic ceramics, which limits their broader applications in emerging fields, such as flexible electronics. A scalable strategy for the fabrication of ultra-flexible crystalline BaTiO 3 nanofiber (NF) films by a sol–gel electrospinning method, followed by a brief calcination, is reported. It facilitates the formation of perovskite BaTiO 3 crystals with intricate grain boundaries at a low temperatures by growing them within polymer NF templates. The ceramic films have a polymer-like softness of 50 mN, a large Young's modulus of 61 MPa, and an elastic strain of 0.9%. Moreover, they have a low density of 28 mg cm −3 and demonstrate superior softness without fracture after deformation. Piezoelectric sensors fabricated based on these films exhibit a high sensitivity of 80 ms with an output voltage of 1.05 V at a pressure of 100 kPa. This approach allows for the large-scale fabrication of flexible BaTiO 3 crystal NF films.
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
ACS Applied Nano Materials
·
2022
·
IF 6.14
Yuqing Chen,Jun Zhou,Yongfei Li,Chengxiang Chen,Beibei Jia,Haomin Guo,Zixuan Zhang,Kai Wu
Polymer-based dielectric composites with inorganic oxide fillers could exhibit synergistic physical and chemical characteristics from both advantages, which have flexible applications in electrical and electronic technology. As composites with various substances, the interfacial structure plays a key role in the electric and dielectric properties. In this work, BaTiO3 particles were embedded in polyvinylidene fluoride (PVDF) by a solution crystallization process. The conductivity and dielectric constant of the composites increased with the increase of the BaTiO3 filler contents. The charge injection and dissipation behavior at the nanointerface of the composite is investigated by Kelvin probe force microscopy. It is found that the charges are more easily injected into the nanointerface between the particle and the polymer. The accumulation and dissipation of surface charges obey the exponential law. The space-charge polarization is also suggested to be a key factor of injection, while the charge dissipation is determined by charge tunneling. The result also demonstrates that the strong interfacial polarization between the BaTiO3 particles and the PVDF matrix plays a crucial role in the dielectric properties. This work provides significant insights into understanding the interfacial charge transport in dielectric composites.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 2
·252
·
IF 5.3
Qi Yuan,Wencai Hu,Tao Wang,Sen Wang,Gaobin Liu,Xueyan Han,Feixiang Guo,Yongheng Fan
In this paper, Nb-doped BaTiO3nanoparticles (BaNb0.47Ti0.53O3) were prepared using an electrochemical method in an alkaline solution, with titanium-niobium alloy as the electrode. The results indicated that under relatively mild conditions (normal temperature and pressure, V < 60 V, I < 5 A), cubic perovskite phase Nb-doped BaTiO3nanoparticles with high crystallinity and uniform distribution can be synthesized. With this increase in alkalinity, the crystallinity of the sample increases, the crystal grain size decreases, and the particles become more equally dispersed. Furthermore, in our study, the average grain size of the nanoparticles was 5–20 nm, and the particles with good crystallinity were obtained at a concentration of 3 mol/L of NaOH. This provides a new idea and method for introducing foreign ions under high alkalinity conditions.Keywords:Nb-BaTiO3;electrochemical synthesis;microstructure;nanoparticles
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2019
·Vol. 30
·期 11
·10651-10659
·
IF 2.195
Huang Xuechen,Liu Bang,Wang Shuanghu,Liu Yuxi,Wu Gang
Bi 2 O 3 - and MgO-doped BaTiO 3 –(Na 1/4 Bi 3/4 )(Mg 1/4 Ti 3/4 )O 3 (BT–NBMT) ceramics were synthesized from a solid-state approach, and then the impacts of Bi 2 O 3 and MgO dosages on the structures and dielectric characteristics were studied. Obvious dual peaks were observed with Bi 2 O 3 dosage to 0.04 and MgO dosage to 0.02. The low-temperature dielectric stability and grain size of the Bi 2 O 3 dopant were improved, while those of the MgO dopant hardly changed with MgO dosage to 0.02, indicating the core/shell microstructure of BT–NBMT was formed following the dissolving-precipitating mechanism of BT systems doped with low-melting-point substances. The low-temperature dielectric stability of the Bi 2 O 3 - or MgO-doped BT–NBMT ceramics first improved and then deteriorated with the increase of doping concentrations. High-temperature stability and diffuse-state transition were found in the optimal ceramics. The second phases of Bi 2 O 3 and MgO, magnesium titanium compounds were observed in Bi 2 O 3 and MgO dopants, respectively. Bi 2 O 3 -doped and MgO-doped ceramics exhibited a fine-grained microstructure and significant grain growth, respectively, and the core/shell microstructure was responsible for the dielectric temperature stability for Bi 2 O 3 dopants and collapsed to a homogeneous one with remarkable grain growth and the second phases for MgO dopants.
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
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 12
·1-16
·
IF 2.8
Wang Fenglin,Mao Haijun,Chen Xingyu,Li Wei,Liu Zhuofeng,Zhang Weijun,Bai Shuxin
In this work, A -site Nd doped BaTiO 3 ceramics in the form of Ba 1− x Nd 2 x /3 TiO 3 with a wide substitution level range of x = 0–0.2 have been prepared via solid-state reaction method. Powder X-ray diffraction results reveal that Nd is completely incorporated into the BaTiO 3 lattice in all specimens. Further analyses based on Rietveld refinement suggest that tetragonal and pseudo-cubic phases coexist in Ba 1− x Nd 2 x /3 TiO 3 ceramics with x ≤ 0.06, and the amount of tetragonal phase is raised with the increase of x value. When x value is larger than 0.08, only pseudo-cubic is observed. The generated \(V^{\prime\prime}_{{{\text{Ba}}}}\) , \({\text{Nd}}_{{{\text{Ba}}}}^{\cdot }\) and \(V_{{\text{O}}}^{{\cdot \cdot }}\) defects, which are identified by X-ray photoelectron spectra, make the grain size displays a tendency of decrease first mainly due to the pining effect, and then increase ascribed to the accelerate of mass diffuse. By introducing such wide range of substitution level, Ba 1− x Nd 2 x /3 TiO 3 ceramics with colossal dielectric constant ( x = 0.08), temperature-stable dielectric properties ( x = 0.15), especially relaxor behavior ( x = 0.20) noticed for the first time, are, respectively, received, which is closely related to the variation of phases and defects induced by the addition of Nd. This study may provide a special idea to modify BaTiO 3 to satisfy diversified applications by single element with a wide doping range, and could lay the foundation of future works focusing on the various potential applications of Ba 1− x Nd 2 x /3 TiO 3 ceramics.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2019
·
IF 3.355
Yanping Wang,Hua Yang,Xiaofeng Sun,Haimin Zhang,Tao Xian
We reported the preparation of new ternary n-BaTiO 3 /Ag/p-AgBr heterostructured photocatalysts and their promising photocatalytic application for the dye degradation. The ternary n-BaTiO 3 /Ag/p-AgBr heterostructured photocatalysts are constructed by coupling n-type BaTiO 3 and p-type AgBr particles onto Ag nanowires. Various methods including XRD, SEM, TEM, XPS, FTIR, UV–vis diffuse reflectance spectroscopy, PL spectroscopy, photocurrent response and EIS were used to characterize the as-prepared photocatalysts. The photodegradation performances of the photocatalysts were assessed by using RhB as the model pollutant and simulated sunlight as the light source. It is demonstrated that the n-BaTiO 3 /Ag/p-AgBr ternary composite photocatalysts exhibit excellent photodegradation performances superior to bare BaTiO 3 and AgBr particles. Particularly, the 20 %BTO/1.2 %Ag/AgBr composite can photocatalyze 99.3 % removal of RhB after 12 min photoreaction, and has a photodegradation activity which is about 3.1 times larger than that of bare AgBr particles. The underlying photodegradation mechanism of the ternary composite photocatalysts was investigated and discussed.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
·
IF 2.605
Xuechen Huang,Hanxing Liu,Hua Hao,Shujun Zhang,Yue Sun,Wenqin Zhang,Lin Zhang,Minghe Cao
MgO-doped 0.97BaTiO 3 –0.03BiYO 3 (0.97BT–0.03BY) polycrystalline ceramics were prepared by the solid-state sintering method. Then the structural, dielectric and resistant properties were investigated as functions of MgO addition. Microstructure was studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectrometry (EDS). The results show that Bi 3+ , Y 3+ and Mg 2+ ions exhibit nonuniform distribution behavior in BT–BY ceramics, demonstrating the existence of a “core–shell” structure, which plays important roles in the capacitance-temperature characteristics, where 0.97BT–0.03BY with the addition 2.2–2.8 at% MgO meets the Electronic Industries Association (EIA) X8R (−55 to 150 °C, ΔC / C 25 °C =±15% or less) specification. Moreover, the fine-grained samples with core–shell structure show much higher bulk resistance than the coarse-grained samples over the studied temperature range, which is attributed to the higher proportion of grain boundaries and the lower concentration of the effective acceptor.
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
危险品化学品经营许可证（带存储）