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为研究核壳量子点的界面电子结构对聚乙烯绝缘电导与空间电荷特性的影响,分别制备了CdSe@ZnS/LDPE、ZnSe@ZnS/LDPE两种核壳量子点纳米复合绝缘,研究了复合绝缘的直流电导和空间电荷的演变规律,并分析了核壳量子点的界面电子结构对电荷陷阱分布特性的影响机理。研究发现,相比于LDPE绝缘,ZnSe@ZnS/LDPE复合绝缘在高温强场条件下直流电导率可降低47.2%,空间电荷积累量降低了40.3%,且陷阱能级增大,表现出对载流子更强的捕获作用。基于密度泛函理论,计算了核壳量子点与聚乙烯绝缘的能带特征。结果表明,核壳纳米量子点的核层–壳层界面、壳层–绝缘界面的能带偏移导致导带底与价带顶发生突变,分别对电子和空穴具有限域作用,且限域效应随着量子点核层与壳层带隙差异增大而逐渐增强,从而限制高温强场下载流子迁移、抑制空间电荷积聚。To investigate the effect of the interface electronic structure of core-shell quantum dots on the conductivity and space charge characteristics of polyethylene insulation, nanocomposite insulations, namely CdSe@ZnS/LDPE and ZnSe@ZnS/LDPE, are synthesized. The study focuses on elucidating the evolution patterns of DC conductivity and space charge within the nanocomposite insulation, accompanied by an analysis of the impact of the interfacial electronic structure of core-shell quantum dots on the distribution of charge traps. Comparative analysis reveals that, in contrast to LDPE insulation, ZnSe@ZnS/LDPE nanocomposite insulation demonstrates a substantial reduction in DC conductivity by 47.2% and a decrease in space charge accumulation by 40.3% under conditions of elevated temperature and strong electric fields. The trap energy level experiences an increase, signifying a heightened trapping effect on carriers. Leveraging density functional theory, the band structure characteristics of core-shell quantum dots integrated with polyethylene are computationally assessed. The findings underscore that the band misalignment at the core-shell interface and the shell-insulation interface induces shifts in the conduction band bottom and valence band top, respectively. These shifts impose a confinement effect on electrons and holes, with the extent of this effect escalating with the augmented band gap difference between the core layer and the shell layer. Consequently, this phenomenon curtails carrier migration, thereby inhibiting space charge accumulation under conditions of elevated temperature and strong electric fields.
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Keywords:
- Nanocomposite insulation /
- Core-shell quantum dots /
- Space charge /
- Carrier migration
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[1] Yu B Q, Xia B, Yang X Y, Wan B Q, Zha J W 2023 Acta Phys. Sin. 72 068402 (in Chinese) [俞葆青,夏兵,杨晓砚,万宝全,查俊伟 2023 物理学报 72 068402]
[2] Li Z L, Du B X 2018 IEEE Electr. Insul. Mag. 34 30
[3] Du B X, Han C L, Li J, Li Z L 2019 Transactions of China Electrotechnical Society 34 179 (in Chinese) [杜伯学,韩晨磊,李进,李忠磊 2019 电工技术学报 34 179]
[4] He J L, Dang B, Zhou Y, Hu J 2015 High Voltage Engineering 41 1417 (in Chinese) [何金良,党斌,周垚,胡军 2015 高电压技术 41 1417]
[5] Mazzanti G, Diban B 2021 IEEE Trans. Power Deliv. 36 3784
[6] Lewis T J 2014 IEEE Trans. Dielect Elect. Insul. 21 497
[7] Tanaka T, Kozako M, Fuse N, Ohki Y 2005 IEEE Trans. Dielect Elect. Insul. 12 669
[8] Takada T, Hayase Y, Tanaka Y 2008 IEEE Trans. Dielect Elect. Insul. 15 152
[9] Zhu X, Wu J, Wang Y, Yin Y 2020 IEEE Trans. Dielect Elect. Insul. 27 450
[10] Li S T, Zhao N, Nie Y J, Wang X, Chen G, Teyssedre G 2015 IEEE Trans. Dielect Elect. Insul. 22 92
[11] Ye C, Zhang D S, Chen B, Tung C H, Wu L Z 2023 Chem. Phys. Rev. 4 011304
[12] Han C L, Du B X, Li J, Li Z L, Tanaka T 2020 IEEE Trans. Dielect Elect. Insul. 27 1204
[13] Yang M, Wang S, Fu J, Zhu Y, Liang J, Cheng S, Hu S, Hu J, He J, Li Q 2023 Adv. Mater. 35 2301936
[14] Smith A M, Lane L A, Nie S M 2014 Nat. Commun. 5 4506
[15] Tanaka T 2019 IEEE Trans. Dielect Elect. Insul. 26 276
[16] Lei Z P, Fabiani D, Bray T, Li C Y, Wang X Y, Andritsch T, Credi A, La Rosa M 2021 IEEE Trans. Dielect Elect. Insul. 28 753
[17] Moyassari A, Unge M, Hedenqvist M S, Gedde U W, Nilsson F 2017 J. Chem. Phys. 146 204901
[18] Chen X, Zhao A X, Li J M, Deng J B, Zhang G J, Zhao X F 2019 J. Appl. Phys. 126 035101
[19] Lv Z P, Ma Y T, Zhang C, Peng J Y, Wu K, Dissado L A 2021 IEEE Trans. Dielect Elect. Insul. 28 616
[20] Simmons J G, Tam M C 1973 Phys. Rev. B 7 3706
[21] Cheng S, Zhou Y, Li Y, Yuan C, Yang M, Fu J, Hu J, He J, Li Q 2021 Energy Storage Mater. 42 445
[22] Dong J F, Deng X L, Niu Y J, Pan Z Z, Wang H 2020 Acta Phys. Sin. 69 217701 (in Chinese) [董久锋,邓星磊,牛玉娟,潘子钊,汪宏 2020 物理学报 69 217701]
[23] Emtage P R, Tantraporn W 1962 Phys. Rev. Lett. 8 267
[24] Hoang A T, Pallon L, Liu D, Serdyuk Y V, Gubanski S M, Gedde U W 2016 Polymers 8 87
[25] Zhou L, Wang X, Zhang Y, Zhang P, Li Z 2019 Materials 12 2657
[26] Akram S, Bhutta M S, Zhou K, Meng P F, Castellon J, Wang P, Rasool G, Aamir M, Nazir M T 2021 IEEE Trans. Dielect Elect. Insul. 28 1514
[27] Fishchuk I I, Kadashchuk A K, Vakhnin A, Korosko Y, Bässler H, Souharce B, Scherf U 2006 Phys. Rev. B 73 115210
[28] Li C, Duan L, Li H, Qiu Y 2014 J. Phys. Chem. C 118 10651
[29] Tu D M, Wang X, Lv Z P, Wu K, Peng Z R 2012 Acta Phys. Sin. 61 01704 (in Chinese) [屠德民,王霞,吕泽鹏,吴锴,彭宗仁 2012 物理学报 61 017104]
[30] Zhang R Z, Chen W H, Yang L N 2012 Acta Phys. Sin. 61 187201 (in Chinese) [张睿智,陈文灏,杨璐娜 2012 物理学报 61 187201]
[31] Hewa-Kasakarage N N, Kirsanova M, Nemchinov A, Schmall N, El-Khoury P Z, Tarnovsky A N, Zamkov M 2009 J. Am. Chem. Soc. 131 1320
[32] Chen X H, Chen Y T, Ren F F, Gu S L, Tan H H, Jagadish C, Ye J D 2019 Appl. Phys. Lett. 115 202101
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