One dimensional MnO2/titanium nitride nanotube coaxial arrays for high performance electrochemical capacitive energy storage

Abstract

One dimensional MnO₂/titanium nitride nanotube coaxial arrays have been designed for a high performance electrochemical capacitive energy storage system based on the concept of fabricating an efficient, fast charge separation network. This nanostructured composite material was prepared by electrodepositing mesoporous MnO₂ into TiN nanotube arrays (TiN NTA), which are prepared by anodization of a Ti foil substrate and subsequent nitridation using ammonia annealing. The electrodeposited mesoporous MnO₂ inside the electrically conductive framework of a TiN nanotube has been found to show high specific capacitance (681.0 F g⁻¹ at 2 A g⁻¹), excellent rate capability (55% capacitance retention from 2 to 2000 mV s⁻¹), and a long cycle life (3% capacitance loss after 1000 cycles). These results demonstrate that this coaxial composite nanostructure is very promising for high performance supercapacitors.