Uniformly Embedded Metal Oxide Nanoparticles in Vertically Aligned Carbon Nanotube Forests as Pseudocapacitor Electrodes for Enhanced Energy Storage

Yingqi Jiang*†,Pengbo Wang†‡,Xining Zang†,Yang Yang†§,Alina Kozinda†, andLiwei Lin†

^†Berkeley Sensor and Actuator Center, Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States

^‡Robotics and Microsystems Center, Soochow University, Suzhou 215021, China

^§Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China

Nano Lett.,2013,13(8), pp 3524–3530

DOI:10.1021/nl400921p

Publication Date (Web): July 30, 2013

Abstract:

Carbon nanotube (CNT) forests were grown directly on a silicon substrate using a Fe/Al/Mo stacking layer which functioned as both the catalyst material and subsequently a conductive current collecting layer in pseudocapacitor applications. A vacuum-assisted, in situ electrodeposition process has been used to achieve the three-dimensional functionalization of CNT forests with inserted nickel nanoparticles as pseudocapacitor electrodes. Experimental results have shown the measured specific capacitance of 1.26 F/cm³, which is 5.7 times higher than pure CNT forest samples, and the oxidized nickel nanoparticle/CNT supercapacitor retained 94.2% of its initial capacitance after 10 000 cyclic voltammetry tests.

Keywords:

Vertically aligned carbon nanotube;nanoparticle;electrodeposition;metal oxide;pseudocapacitor;energy storage