Building a high-performance supercapacitor with α-MnO₂@nitrided TiO₂/carbon fiber paper porous structure

MnO₂ is considered as a promising electrode material for supercapacitors because of its low cost, high abundance, large theoretical specific capacitance and environmentally friendly nature. How to obtain high-performance MnO₂ electrode material with high mass loading via a low-cost synthesis method has attracted considerable attention and still remained a huge challenge. Herein, nitrided TiO₂ nanorod arrays (N-TiO₂) were successfully prepared on carbon fiber paper (CFP) by a novel seeded hydrothermal synthesis and thermal nitridation, and then hierarchical porous α-MnO₂ nanoflowers entwined with nanoribbons were grown on the nitrided TiO₂/CFP electrode. Hierarchical porous nanoflowers entwined with nanoribbons and nanorod arrays provide appropriate geometries and electronic structures, helping suppress stack tendency at high mass loading and improve the specific capacitance of electrode. The α-MnO₂@N-TiO₂/CFP electrode with high mass-loading of 20.9 mg·cm⁻² shows a high areal capacitance of 3.0 F·cm⁻² at 1 mA·cm⁻² and excellent cycling stability with no capacitance reduction after 5000 cycles. The high performance makes the α-MnO₂@N-TiO₂/CFP electrode a promising electrode material for supercapacitor applications.