CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Junwei Zhang,Hui Lin,Wenhui Lou,Ruijin Hong,Zhaoxia Han,Dawei Zhang
Photo-stimulated luminescence materials have shown significant potential in the field of information storage, but they still face critical challenges in the regulation of trap levels. Herein, Ba 0.75 Al 11 O 17.25 :Eu 2+ fluorescent ceramics with abundant deep traps (1.24 eV) were reported via selective Mn 2+ co-doping. This material exhibits a homogeneous and dense crystalline structure, and its narrow-band emission at 514 nm is attributed to the energy transfer of Eu-Mn. Thermoluminescence curves, X-ray photoelectron spectroscopy and electron paramagnetic resonance spectra confirm that the trap levels primarily arise from oxygen vacancies and Reidinger defects, and Mn 2+ doping suppresses the formation of shallow traps through charge compensation mechanism. Significantly, information writing and reading in the ceramic medium were achieve using 254 nm UV light and 980 nm NIR light or thermal stimulation. The excellent photo-stimulated luminescence properties and high read-write stability of Ba 0.75 Al 11 O 17.25 :Eu 2+ , Mn 2+ are expected to accelerate the development of the next generation of optical storage technology.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Mingti Wang,Shixun Hu,Wenjia Zhang,Yuxiao Zhou,Shangshi Huang,Jiahui Zhang,Qi Zhang,Changlong Yang,Qi Li,Hao Yuan,Jinliang He
Polypropylene (PP) is believed to be a rather promising cable insulating material for high-capacity electric power system with low carbon emission due to its decent thermo-resistance and recyclable nature. In this paper, a new dually chemical grafting modification strategy by methyl acrylate (MA) and acrylic acid (AA) is put forward to tailor the charge transportation behavior in PP, thus further enhancing the electrical properties. Experimental results indicate that the dually grafted PP with 2.3 weight percent (wt%) MA and 1.9 wt% AA shows enhanced volume resistivity and electrical breakdown strength than pure PP, and the space charge injection is significantly suppressed. This work further adopts thermally stimulated depolarization current (TSDC) test and computational analysis based on density functional theory (DFT) to reveal the mechanism of enhancement. The analysis shows that grafted chemical groups can introduce quantities of deep traps and electrostatic potential wells which are strongly correlated with the carbonyl group and would hinder the charge transportation thus improving the electrical insulating performances of PP. This work would provide a new route of PP-based dually grafting modification for the development of high-voltage cable insulation.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Feng Gao,Qing Pang,Dangli Gao,Chaoyang Jia,Hong Xin,Yong Pan,Yuhua Wang,Sining Yun
Photostimulable luminescence (PSL) nanophosphors, which exhibit superior features including controllable energy storage and efficient photon release upon light stimulation, are desirable for optical signal storage. However, trap tuning of the storage phosphor remains a great challenge. Herein, the PSL of Zn2GeO4:Mn2+ nanophosphors is enhanced via creating deep traps through nonequivalent Pr3+ doping. The possible enhanced mechanisms are analyzed combined with doping models using the first-principles theory. A mechanism is proposed based on changing the coordination environment of Mn2+, creating deep traps and tuning the band gap structure, and thus providing the chance for electrons’ photoionization and PSL generation. As a result, the prepared nanophosphors demonstrate the superior functionalities for optical signal storage. This work not only offers an insight into defect engineering through doping strategies for developing PSL materials but also supplies a good candidate for optical information storage.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
High Voltage
·
2020
·Vol. 5
·期 3
·249-255
·
IF 3.027
Shixun Hu,Yao Zhou,Chao Yuan,Wei Wang,Jun Hu,Qi Li,Jinliang He
Polypropylene (PP)-based nanocomposite is a promising insulation material for recyclable high-voltage direct current (HVDC) cables, where the coupling agent plays an important role. In this study, four silane coupling agents with different alkyl chain groups (methyl, propyl, octyl, and octadecyl) were used to surface-modify magnesium oxide (MgO) nanoparticles. The surface-modification effect on the electrical properties of PP/MgO nanocomposites was investigated. The results show that surface-modified nanoparticles introduce quantities of deep traps, whose quantity increases as the alkyl chain length increases. The similar tendency also occurs on DC volume resistivity. All these nanocomposites show remarkable space charge suppression ability and improved DC breakdown strength. Among them, the nanocomposites with octyl-modified MgO show the best electrical properties, which could be attributed to the introduction of a large quantity of deep traps. The work may give a reference for the selection of coupling agents in PP-based nanocomposite insulation material for HVDC cable.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
High Voltage
·
2024
·
IF 4.4
Yunxiao Zhang,Wenxin Lin,Yuanxiang Zhou,Weiwei Xing,Jiayu Cheng,Chenyuan Teng
Electrical tree degradation is one of the main causes of insulation failure in high-frequency transformers. Electrical tree degradation is studied on pure epoxy resin (EP) and MgO/EP composites at frequencies ranging from 50 Hz to 130 kHz. The results show that the tree initiation voltage of EP decreases, while the growth rate and the expansion coefficient increase with frequency. Moreover, the bubble phenomenon at high frequencies in EP composites is discussed. Combined with trap distribution characteristics within the material, the intrinsic mechanism of epoxy composites to inhibit the growth of the electrical tree at different frequencies is discussed. It can be concluded that more deep traps and blocking effect are introduced by doping nano-MgO into EP bulks, which can improve the electrical tree resistance performance of EP composites in a wide frequency range.
研究领域:
电气工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 34
·345709
·
IF 3.953
Beibei Jia,Jun Zhou,Yuqing Chen,Zepeng Lv,Haomin Guo,Zixuan Zhang,Zihe Zhu,Haoyu Yu,Yang Wang,Kai Wu
Charge transport in insulating composites is fundamental to designing high performance in electrical breakdown strength processes. A fundamental understanding of the charge transport at nanoscale in insulating composites remains elusive. Herein, we fabricate two types of interfaces in epoxy (EP) composites (Al2O3/EP and bubble/EP, respectively). Then the local dynamic charge mobility behavior and charge density are explored using in situ Kelvin probe force microscopy. After the external voltage in the horizontal direction is applied, significant differences are demonstrated in the evolution of charge transport for epoxy matrix, filler/bubble, and their interface, respectively. The interface between Al2O3 and epoxy is easier to accumulate the negative charges and introduce shallow traps. Lots of positive charges are located around a bubble where deeper traps are present and could prevent charge migration. Thus, this work offers extended experimental support to understanding the mechanism of charge transport in dielectric composites.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 20
·10954-10963
·
IF 2.936
Ting Song,Meng Zhang,Yuxue Liu,Jian Yang,Zheng Gong,Hong Yan,Hancheng Zhu,Duanting Yan,Chunguang Liu,Changshan Xu
Spinel-phase Zn2Ga2.98Ge0.75–xSnxO8:Cr0.023+ (ZGGSO:Cr3+) nanoparticles with various Sn4+ concentrations were prepared by a hydrothermal method in combination with a post-annealing in vacuum at high temperature. For these nanoparticles, the observed near infrared (NIR) persistent luminescence peaked at ∼697 nm and originates from the 2E, 4T2 (4F) → 4A2 transitions of Cr3+ and the afterglow time exceeds 800 min. For both the interior and surface Cr3+ ions in the ZGGSO host, it can be found that the increased energy transfer from Cr3+ to the deep trap (anti-site defects, ) after the substitution of Ge4+ by Sn4+ plays a key role in enhancing the persistent luminescence of the ZGGSO:Cr3+ nanoparticles. Strikingly, this energy transfer process can be controlled through the variations in the crystal field strength and the trap depths. Our results suggest that not only Sn4+ substitution can improve in vivo bioimaging but also the existence of deep traps in ZGGSO:Cr3+ nanoparticles is helpful for retracing in vivo bioimaging at any time.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Chao Tan,Weilong Liu,Wenzhuo Li,Hongbo Qi,Xiaojun Zhu,Zhongfang Ji,Jian Cheng,Wenzhi Wu,Qingxin Yang
Appropriately doped lead-free double perovskites (LFDPs) or vacancy-ordered double perovskites (VODPs) exhibit efficient and stable white-light emission via self-trapped excitons (STEs), and therefore hold significant potential for applications in lighting and display technologies. However, the intrinsic luminescence of the host is often disregarded when studying the doped materials because most LFDPs or VODPs possess indirect bandgaps or parity-forbidden transitions from conduction band to valence band. Here, we report a weak warm white light emission from pure Cs2SnCl6 microcrystals, and attribute this emission to the deep trap state according to the observations of absorption and photoluminescence (PL) spectra. The bandgap and structural characteristics of Cs2SnCl6 were further illustrated by analyzing the absorption, PL, Raman spectra and PL dynamics under variable pressure and temperature conditions. The emission mechanism of the deep trap levels in Cs2SnCl6 microcrystals and their potential impact on the STEs emission were discussed based on the spectroscopic observations.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Deng Hu,Hang Luo,Yuan Liu,Fan Wang,Bo Peng,Xiaona Li,Huan Wang,Guanghu He,Dou Zhang
Dielectric capacitors are indispensable energy storage components in both civilian applications and industrial processes. Under elevated temperatures and intense electric fields, polymer dielectrics usually suffer from an inevitably increase in conductivity, leading to a significant reduction in breakdown strength, energy density and efficiency. This investigation aims to design an all-organic dielectric with enhanced high-temperature capacitive performance by introducing a small molecule P-xylene F (PF) into polyetherimide (PEI). Two mechanisms including the incorporation of deep trap energy levels via wide bandgap fillers and the electrostatic interactions by hydrogen bonding between the fillers and the polymer matrix are proposed to support the enhancement. The hydrogen bonding between PF and polyamic acid (PAA)chains induces the formation of physical cross-linking between PF and the negatively charged benzene rings in PEI after imidization. This influences benzene ring stacking within the polymer chains and enhances the film’s mechanical strength. Additionally, PF’s wider bandgap compared to PEI introduces deep trap energy levels, hindering carrier transport and reducing conductive losses at high temperatures. As results, the dielectric achieves an energy density (U d ) of 4.47 J/cm 3 with an efficiency (η) above 90 % at 200 °C. Its excellent stability is also demonstrated with over 210,000 charge–discharge cycles at 200 °C. This study promotes the development of high-performance dielectrics at high temperature.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2021
·
IF 3.512
Yi Qin,Shudong Zhang,Shuai Han,Tingting Xu,Cui Liu,Min Xi,Xinling Yu,Nian Li,Zhenyang Wang
Cycloaliphatic epoxy (CE) resin plays a vital role in insulation equipment due to its excellent insulation and processability. However, the insufficient ability of CE to confine electrons under high voltage often leads to an electric breakdown, which limits its wide applications in high-voltage insulation equipment. In this work, the interface effect of inorganic nano-SiO2 introduces deep traps to capture electrons, which is synergistic with the inherent ability of the voltage stabilizer m-aminobenzoic acid (m-ABA) to capture high-energy electrons through collision. Therefore, the insulation failure rate is reduced owing to doping of the functionalized nanoparticles of the m-ABA-grafted nano-SiO2 (m-ABA-SiO2) into the CE. It is worth noting that the breakdown field strength of this m-ABA-SiO2/CE reaches 53 kV/mm, which is 40.8% higher than that of pure CE. In addition, the tensile strength and volume resistivity of m-ABA-SiO2/CE are increased by 29.1 and 140%, respectively. Meanwhile, the glass transition temperature was increased by about 25 °C and reached 213 °C. This work proves that the comprehensive performance of CE-based nanocomposites is effectively improved by m-ABA-SiO2 nanoparticles, showing great application potential in high-voltage insulated power equipment.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
·
2022
·Vol. 30
·期 1
·484-487
·
IF 2.509
Yao Zhou,Yujie Zhu,Chao Yuan,Qi Li,Xiangdong Xu,Yuriy Serdyuk,Qing Wang,Jinliang He
Polymer nanocomposites are the material of choice for dc insulation. The emerging demand for high-capacity high voltage direct current (HVdc) power transmission requires polymer nanocomposites capable of safe and stable operation at high temperatures. However, the high-temperature electrical properties of current polymer nanocomposites are still unsatisfactory. Here, we report that the modulation of polymer/nanoparticle interfaces can greatly improve the high-temperature insulation properties of polypropylene (PP)-based nanocomposite for recyclable HVdc cable insulation application. The nanoparticles are surface-modified with PP-graft-maleic anhydride (PP-
${g}$
-mah), which is not only well miscible with PP but also contains polar groups to act as interfacial deep traps. We demonstrate that the interfacial deep traps can improve the dc breakdown strength and the electrical resistivity of polymer nanocomposite by inhibiting the charge injection. This work deepens the understanding of interfacial effects in polymer nanocomposites and provides new opportunities for designing high-performance recyclable insulation materials for HVdc cables.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2022
·Vol. 57
·期 8
·5036-5049
·
IF 4.682
Zhang Xing,Yang Fanghong,Sun Xiaopeng,Li Wenfei,Yao Zhanhai
Graphene (GR) has attracted wide attention as a filler for nanocomposites due to unique electrical properties, high specific surface area and mechanical strength. However, it is difficult to disperse uniformly in matrix because of its high surface energy. In this work, the nanocomposites with high DC breakdown strength are successfully prepared by blending newly synthesized voltage stabilizer noncovalent functionalized GR into linear low density polyethylene/linear low density polyethylene-graft-polystyrene (LLDPE/PES). The results show that the electrical insulation properties of nanocomposites are improved significantly due to the introduction of a great number of deep traps by GR. The internal space charge is suppressed obviously and DC breakdown strength of the nanocomposite prepared by introducing 3.0 wt% voltage stabilizer and 0.005 wt% GR reaches 400.1 kV mm −1 , which is 41.6% higher than that of pure LLDPE. This study provides a new strategy for the development of polyethylene insulating materials by introducing noncovalent functionalized GR. Graphical abstract
研究领域:
材料科学
·
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）