Metal oxides nanoarray electrodes for flexible supercapacitors

This chapter summarizes the recent process of nanoarray electrodes for flexible supercapacitors. It focuses on synthetic strategies of self-supported metal oxide array materials including solution-based method, electrochemical assisted electrodeposition and chemical vapor deposition. Hybrid nanostructure arrays are usually fabricated by multi-step approaches assisted by the interfacial reaction between the different oxide nanostructures arrays. In practical applications, the energy density and power density of metal oxide electrodes are two crucial issues. One promising approach is to fundamentally increase the electrical conductivity of metal oxides by fabricating nanoarrays, aiming to enlarge the specific surface area and shorten the electron conduction length. Another way is to load electrode materials onto the conductive and flexible array supports. The chapter highlights the geometry of nanostructured arrays such as one-dimension (1D) nanowires, nanorods, nanotubes, nanospikes, two-dimension (2D) nanoflakes/nanowalls and the integration of 1Dat2D nanoarrays.