Zinc Ferrite Anchored Multiwalled Carbon Nanotubes for High-Performance Supercapacitor Applications

Abstract

Recently, thin-film supercapacitors have received much interest because they can achieve both high energy densities and high power densities, which make them suitable for practical applications. Here, thin films consisting of zinc ferrite (ZnFe2O4) anchored on multiwalled carbon nanotubes (CNT) were prepared through a simple and inexpensive “successive ionic layer adsorption and reaction (SILAR)” method. This method has the advantage of direct electrode formation without the use of any binder. The synergy of the composite electrode (ZnFe2O4–CNT) yields a high specific capacity of 217 mAh g–1 at 5 mV s–1, which is realized by contributions from the inner and outer active surfaces of the hybrid ZnFe2O4–CNT electrode. Furthermore, a solid-state symmetric device exhibits a highest specific energy of 12.80 Wh kg–1 and a specific power of 377.86 W kg–1, which clearly demonstrates that our hybrid ZnFe2O4–CNT electrode is promising and innovative for energy-storage applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim