Hydroxide ion dependent α-MnO2 enhanced via oxygen vacancies as the negative electrode for high-performance supercapacitors

Oxygen vacancy-enhanced α-MnO₂ has a high specific capacitance of 736.3 F g⁻¹. The energy storage process of MnO₂ as the anode is realized by the participation of OH⁻ and the mutual conversion of Mn(ii), Mn(iii) and Mn(iv).