Stabilized TiN Nanowire Arrays for High-Performance and Flexible Supercapacitors
Stabilized TiN Nanowire Arrays for High-Performance and Flexible Supercapacitors
复制标题
用于高性能柔性超级电容器的稳定 TiN 纳米线阵列
DOI：
10.1021/nl302761z
复制
发表时间：
2012-10-01
期刊：
影响因子：
10.8
通讯作者：
Li, Yat
中科院分区：
文献类型：
--
作者：
Lu, Xihong;Wang, Gongming;Li, Yat
金属氮化物作为高性能超级电容器的电极材料受到越来越多的关注。然而，它们中的大多数都存在骑行稳定性差的问题。这里我们以TiN为例来说明电容损失的机理。X射线光电子能谱分析表明，这种不稳定性是由于锡在充放电过程中发生不可逆的电化学氧化所致。值得注意的是，我们首次证明了使用聚乙烯醇(PVA)/KOH凝胶作为电解液，可以在不牺牲其电化学性能的情况下稳定锡。聚合物电解液抑制了电极表面的氧化反应。电化学研究表明，TiN固态SCs在15000次循环下表现出极高的稳定性，并获得了0.05MWh/cm(3)的高体能量密度。有效稳定氮化物材料的能力为开发高性能和柔性的超临界流体材料开辟了新的机遇。
Metal nitrides have received increasing attention as electrode materials for high-performance supercapacitors (SCs). However, most of them are suffered from poor cycling stability. Here we use TiN as an example to elucidate the mechanism causing the capacitance loss. X-ray photoelectron spectroscopy analyses revealed that the instability is due to the irreversible electrochemical oxidation of TiN during the charging/discharging process. Significantly, we demonstrate for the first time that TiN can be stabilized without sacrificing its electrochemical performance by using poly(vinyl alcohol) (PVA)/KOH gel as the electrolyte. The polymer electrolyte suppresses the oxidation reaction on electrode surface. Electrochemical studies showed that the TiN solid-state SCs exhibit extraordinary stability up to 15 000 cycles and achieved a high volumetric energy density of 0.05 mWh/cm(3). The capability of effectively stabilizing nitride materials could open up new opportunities in developing high-performance and flexible SCs.