Controlled growth of spinel NiCo2O4 nanostructures on carbon cloth as a superior electrode for supercapacitors
Controlled growth of spinel NiCo2O4 nanostructures on carbon cloth as a superior electrode for supercapacitors
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DOI：
10.1039/c3ra46399k
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发表时间：
2014-01-01
期刊：
影响因子：
3.9
通讯作者：
Selladurai, S.
中科院分区：
文献类型：
--
作者：
Padmanathan, N.;Selladurai, S.
在本研究中，采用简单的水热方法，采用不同的前驱盐，实现了碳纤维布（CFC）上双金属NiCo2O4纳米结构的形态转化。正如预期的那样，通过改变前驱体，成功地驱动了表面形貌。硝酸和氯化物前驱体分别生长出典型的NiCo2O4纳米壁网络和多孔纳米片微观结构。由于其独特的结构特点，它们在超级电容器应用中表现出不同的电化学活性。生长的NiCo2O4纳米墙网络结构在5 a g（-1）的高电流密度下提供了1225 F g（-1）的最大电容和出色的耐用性。然而，在电流密度为1ag（-1）时，NiCo2O4纳米片的有限比电容仅为844 F g（-1）。这种比电容、倍率和循环稳定性等电化学特性的变化主要是由于它们在生长过程中受到前驱体驱动的结构差异造成的。研究结果表明，不同阴离子的前驱体对金属氧化物纳米结构的生长动力学也有很大影响。在这种情况下，我们建议直接生长具有所需微观结构的NiCo2O4@CFC将成为下一代柔性超级电容器的潜在电极。
In this study, the morphology conversion of bimetallic NiCo2O4 nanostructures on carbon fiber cloth (CFC) was achieved via a simple hydrothermal approach with different precursor salts. As expected, the surface morphology has been successfully driven by varying the precursor. Typical NiCo2O4 nanowall-networks and porous nanoflake microstructures have been grown when using the nitrate and chloride precursors respectively. As an advantage of their unique structural features, they have shown different electrochemical activity towards supercapacitor applications. The as-grown NiCo2O4 nanowall-network structure delivers a maximum capacitance of 1225 F g(-1) at a high current density of 5 A g(-1) and excellent durability. However, a limited specific capacitance of only 844 F g(-1) at a current density of 1 A g(-1) was achieved for NiCo2O4 nanoflakes. This variation in the electrochemical features such as specific capacitance, rate capability and cyclic stability is mainly due to their structural discrepancies which have been driven by the precursors during the growth process. From this investigation it can be concluded that precursors with different anions also greatly influence the growth kinetics of metal oxide nanostructures. In this case, we suggest that the directly grown NiCo2O4@CFC with the desired microstructure will be a potential electrode for next generation flexible supercapacitors.