A novel heterostructure of oriented core/shell tungsten oxide nanorod arrays for electrochromo-pseudocapacitor

Good dual electrochromic-capacitive performances and long life are both important for an electrochromo-pseudocapacitor. In this paper, a novel heterostructure, which is fabricated using well-oriented hexagonal WO3 nanorod arrays as the core and amorphous WO3−x as the shell, has been proved to possess excellent electrochromic and pseudocapacitive properties. The annealing temperatures for coating the shell take great influence on its microstructure, especially the crystallinity, thus on the comprehensive properties of the heterostructure. Results show that the heterostructure reaches the optimal state at 250 °C with short response times (14, 10.5 s) and high specific capacitance (716.8 F·g−1) while maintaining good stability.