دانلود رایگان مقاله لاتین سنتز نانوبلور از سایت الزویر
عنوان فارسی مقاله:
سنتز و توصیف پیشرفته نانوبلورهای Li3V2(PO4)3 @ هدایت پلیمر PEDOT برای باتری های لیتیوم-یون انرژی بالا
عنوان انگلیسی مقاله:
Synthesis and characterization of advanced Li3V2(PO4)3 nanocrystals@conducting polymer PEDOT for high energy lithium-ion batteries
سال انتشار : 2017
برای دانلود رایگان مقاله سنتز نانوبلور اینجا کلیک نمایید.
مقدمه انگلیسی مقاله:
1. Introduction
Nowadays, rechargeable lithium-ion batteries are used in a wide range of applications from small portable electronic devices to hybrid electric vehicles (HEVs) or electric vehicles (EVs) [1,2]. Since the energy density of lithium-ion batteries is mainly determined by the intercalation compound cathodes, the cathode materials with high theoretical capacity, high operating voltage and low cost are widely investigated. Among currently studied cathodes for lithium-ion batteries, NASICON-type monoclinic Li3V2(PO4)3 electrode has become one of the most promising materials due to its high theoretical capacity, good safety and low cost [3–5]. It can completely extract three Li-ions when charged to a higher voltage of 4.8 V, which leads to a theoretical capacity of 197 mAh g−1 [6,7]. Moreover, Li3V2(PO4)3 also exhibits a high operating voltage plateau (ca. 4.0 V), resulting in high energy density. Unfortunately, the low intrinsic electronic conductivity (ca. 2.4 × 10−7 S cm−1) and low Li-ion diffusion coefficient (10−10–10−9 cm2 s−1) of the pure Li3V2(PO4)3 electrode lead to a poor high rate performance, which thus limit its practical application [8].Up to now, there have been several approaches to overcome the issues listed above. One effective way is to improve the intrinsic low conductivity by doping an appropriate amount of other alien ions (such as Mg2+ [9], Fe3+ [10], Nd3+ [11], Na+ [12], etc.) which can form a continuous conductive path in the electrode. Surface coating is another feasible way to enhance the battery performance by virtue of modifying the surface chemistry or providing protection layers to minimize the direct contact between the active material and electrolyte [13–15]. Among them, coating conductive carbon [16–21] can overcome the low electron conductivity of Li3V2(PO4)3 electrode, but the irregular coating may lead to poor connectivity of the particles and hence capacity loss. What’s more, the Li-ion diffusion rate and the amount of lithium extracted from Li3V2(PO4)3 can be manipulated by synthesizing nanometer grain sizes [19], and thus the electrode material with nanometer sized particles is an ideal morphology to effectively improve the rate performance. Although these methods help to improve the battery performance of Li3V2(PO4)3, it still remains a challenge to realize its practical application for energy storage. Recently, conducting polymers, such as polypyrrole (PPy) [22–24], polythiophene (PT) [25], polyaniline (PANI) [26,27], poly(3,4-ethylenedioxythiophene) (PEDOT) [28–31] have been used as coating agents for electrode surfaces in terms of improving the electronic conductivity and mechanical flexibility. Composite electrode materials with PEDOT are especially attractive interms of high electronic conductivity, contribution to the electrode capacity and the ability to improve Li-ion transport [32]. For example, Zhang et al. fabricated Li4Ti5O12 modified with PEDOT via a facile method to enhance the rate performance [31]. Previously, Kang et al. reported that the battery performances of Li3V2(PO4)3 can be significantly improved by coating it with the conducting polymer PEDOT under mild processing conditions at low temperature without any conductive carbon, and the coating by means of oxidant-free polymerization led to an exceptionally high power capability with outstanding cycle stability [28]. Nevertheless, the Li3V2(PO4)3 should be partially delithiated during the synthesis process to oxidize the vanadium ions on the surface of the particles and it is difficult to control the composition of Li3-xV2(PO4)3. Thus, a facile and an effective strategy to synthesize PEDOT coated Li3V2(PO4)3 cathode should be developed toward superior rate capability and cycle performance. In this study, the core-shell Li3V2(PO4)3@PEDOT composite is synthesized through a hydrothermal method followed by a chemical polymerization in the presence of oxidant. The structure, morphology and electrochemical performance of Li3V2(PO4)3@PEDOT electrode are investigated and compared with that of Li3V2(PO4)3 and Li3V2(PO4)3@C samples. Benefiting from the PEDOT coating layer with enhanced electronic conductivity,the Li3V2(PO4)3@PEDOT exhibits superior rate capability and cycling performance when used as cathode material for lithium-ion batteries.
برای دانلود رایگان مقاله سنتز نانوبلور اینجا کلیک نمایید.
کلمات کلیدی:
Synthesis and characterization of advanced high capacity cathode ... www.sciencedirect.com/science/article/pii/S0925838816303206 by E Bulut - 2016 - Cited by 2 - Related articles Synthesis and characterization of advanced high capacity cathode active nanomaterials with three integrated spinel-layered phases for Li-ion batteries. Synthesis and Characterization of Advanced Materials (ACS ... https://www.amazon.com/Synthesis-Characterization-Advanced.../dp/0841235406 Buy Synthesis and Characterization of Advanced Materials (ACS Symposium Series) on Amazon.com ✓ FREE SHIPPING on qualified orders. Synthesis and Characterization of Advanced Carbon-Based ... https://www.intechopen.com/...advances/synthesis-and-characterization-of-advanced-car... by V Salles - 2012 - Cited by 1 - Related articles Synthesis and Characterization of Advanced Carbon-Based Nanowires – Study of Composites Actuation Capabilities Containing These Nanowires as Fillers ... Synthesis and Characterization of Novel Multiaromatic Epoxy Resin ... ieeexplore.ieee.org/document/4441455/ by Z Tao - 2007 - Related articles Synthesis and Characterization of Novel Multiaromatic Epoxy Resin for Advanced Microelectronic Packaging Applications. Abstract: The novel multiaromatic ... Synthesis and Characterization of Uniform Nanowires of Trigonal ... onlinelibrary.wiley.com/.../1616-3028(200203)12:3%3C219::AID-ADFM219%3E3.... by B Gates - 2002 - Cited by 383 - Related articles Mar 7, 2002 - Advanced Functional Materials. Explore this journal >. Advanced ... Synthesis and Characterization of Uniform Nanowires of Trigonal Selenium ... Synthesis and Characterization of Advanced Materials https://books.google.com/books?id=ezwrAAAAYAAJ Robert A. Laudise - 1984 - Materials Such multidisciplinary projects require the ability to conduct research in depth, whether it is synthesis, characterization, or theory. An appreciation of those ... Synthesis and characterization of manganese tetroxide (Mn3O4 ... link.springer.com/article/10.1007/s40145-013-0037-1 by B Sahoo - 2013 - Cited by 3 - Related articles Journal of Advanced Ceramics. March 2013 , Volume 2, Issue 1, pp 26–30. Synthesis and characterization of manganese tetroxide (Mn3O4) nanofibers by ...
