Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
N-doped carbon-coated ultrasmall Nb2O5 nanocomposite with excellent long cyclability for sodium storage.
Nanoscale ( IF 5.8 ) Pub Date : 2020-08-12 , DOI: 10.1039/d0nr04922k Zhigao Chen 1 , Weimin Chen , Hongxia Wang , Zhuangwei Xiao , Faquan Yu
Nanoscale ( IF 5.8 ) Pub Date : 2020-08-12 , DOI: 10.1039/d0nr04922k Zhigao Chen 1 , Weimin Chen , Hongxia Wang , Zhuangwei Xiao , Faquan Yu
Affiliation
|
Niobium pentoxide (Nb2O5) has drawn significant interest as a promising anode for sodium ion batteries (SIBs) due to its large interplanar lattice spacing and relatively high diffusion efficiency. However, the intrinsic drawbacks of low electrical conductivity and substantial volume change greatly impede its practical applications in large-scale energy storage systems. In this work, ultrasmall Nb2O5 nanoparticles wrapped with nitrogen-doped carbon (denoted as Nb2O5@NC) were delicately synthesized via a facile sol–gel method and subsequent heat treatment. The unique structure of ultrasmall Nb2O5 nanoparticles in a carbonaceous matrix can not only effectively shorten the transmission distance for both ions/electrons but also relieve the strain and stress caused by volume variation during the sodiation/desodiation process. In addition, the synergistic effect of nitrogen doping and carbon coating can further improve the electronic conductivity and pseudocapacitive behavior of the active materials, thus promoting the rapid electrochemical reaction kinetics of the Nb2O5@NC composite. The obtained 600-Nb2O5@NC-2 anode exhibits superior rate capability and outstanding cycling stability, delivering a reversible capacity of 196 mA h g−1 at 1 A g−1 after 1000 cycles. Even at high current densities of 5 A g−1 and 10 A g−1, the long-life cycling tests show that the reversible capacities still remain at 128.4 mA h g−1 and 95.9 mA h g−1 after 3000 cycles, respectively, which is the best performance of Nb2O5-based anodes at high current densities so far. These results indicate that the feasible synthetic strategy of Nb2O5@NC is an effective approach to develop high-performance Nb2O5-based anodes for large-scale energy storage.
中文翻译：
氮掺杂碳包覆的超小Nb2O5纳米复合材料，具有优异的长循环性，可用于钠存储。
五氧化二铌（Nb 2 O 5）作为钠离子电池（SIB）的有希望的阳极，由于其较大的面内晶格间距和相对较高的扩散效率而引起了人们的极大兴趣。但是，低电导率和大量体积变化的固有缺点极大地阻碍了其在大规模储能系统中的实际应用。在这项工作中，通过简便的溶胶-凝胶法和随后的热处理精细地合成了包裹有氮掺杂碳的超小Nb 2 O 5纳米颗粒（表示为Nb 2 O 5 @NC）。超小型Nb 2 O 5的独特结构碳质基质中的纳米颗粒不仅可以有效地缩短离子/电子的传输距离，而且还可以缓解在增氧/脱氧过程中由于体积变化而引起的应变和应力。此外，氮掺杂和碳包覆的协同作用可以进一步提高活性材料的电子电导率和拟电容行为，从而促进Nb 2 O 5 @NC复合材料的快速电化学反应动力学。将得到的600-的Nb 2 ö 5 @ NC-2阳极表现出优异的倍率性能和出色的循环稳定性，提供196毫安Hg的可逆容量-1 1 A G -1经过1000个周期。即使在5 A g -1和10 A g -1的高电流密度下，长寿命循环测试显示，在3000次循环后，可逆容量仍分别保持在128.4 mA hg -1和95.9 mA hg -1，这到目前为止，Nb 2 O 5基阳极的最佳性能是其最高性能。这些结果表明，Nb 2 O 5 @NC的可行合成策略是开发用于大规模储能的高性能Nb 2 O 5基阳极的有效方法。
更新日期：2020-09-24
中文翻译：
氮掺杂碳包覆的超小Nb2O5纳米复合材料，具有优异的长循环性，可用于钠存储。
五氧化二铌（Nb 2 O 5）作为钠离子电池（SIB）的有希望的阳极，由于其较大的面内晶格间距和相对较高的扩散效率而引起了人们的极大兴趣。但是，低电导率和大量体积变化的固有缺点极大地阻碍了其在大规模储能系统中的实际应用。在这项工作中，通过简便的溶胶-凝胶法和随后的热处理精细地合成了包裹有氮掺杂碳的超小Nb 2 O 5纳米颗粒（表示为Nb 2 O 5 @NC）。超小型Nb 2 O 5的独特结构碳质基质中的纳米颗粒不仅可以有效地缩短离子/电子的传输距离，而且还可以缓解在增氧/脱氧过程中由于体积变化而引起的应变和应力。此外，氮掺杂和碳包覆的协同作用可以进一步提高活性材料的电子电导率和拟电容行为，从而促进Nb 2 O 5 @NC复合材料的快速电化学反应动力学。将得到的600-的Nb 2 ö 5 @ NC-2阳极表现出优异的倍率性能和出色的循环稳定性，提供196毫安Hg的可逆容量-1 1 A G -1经过1000个周期。即使在5 A g -1和10 A g -1的高电流密度下，长寿命循环测试显示，在3000次循环后，可逆容量仍分别保持在128.4 mA hg -1和95.9 mA hg -1，这到目前为止，Nb 2 O 5基阳极的最佳性能是其最高性能。这些结果表明，Nb 2 O 5 @NC的可行合成策略是开发用于大规模储能的高性能Nb 2 O 5基阳极的有效方法。
京公网安备 11010802027423号