High-performanced flexible solid supercapacitor based on the hierarchical MnCo2O4 micro-flower

Transition metal oxides have attracted much attention in supercapacitors(SCs) research field due to their eco-friendly characteristics and high theoretical specific capacity. However, the slow reaction kinetics process and poor long-cycle performance hinder its potential application. To overcome these shortcomings, MnCo2O4 micro -flowers (MnCo2O4-MF) with hierarchical structure were prepared. The spinel MnCo2O4 has a variety of metal valence states, which can provide more electrochemical active sites compared to mono-metal oxides. Moreover, the unique hierarchical structure of MnCo2O4-MF shortens the transmission distance of ions and electrons, and reduce the volume expansion and structural collapse during the cycles. Benefiting from the crystal phase and structure advantages of MnCo2O4-MF, the reaction kinetics process was accelerated and it showed excellent long -cycle stability. In aqueous alkaline electrolyte, MnCo2O4-MF exhibits an ultra-high specific capacity of 1230 F g-1 at a current density of 1 A g-1. Even after 10,000 cycles at 10 A g-1, the capacity of 102.67% is still maintained. In addition, we constructed the sandwich structured flexible flexible hybrid solid supercapacitor (FHSC) based on MnCo2O4-MF // carbon nanoboxes. The FHSC devices not only expand the working voltage window of SCs, but also show flexibility and excellent electrochemical performance.

Automated summary

Transition metal oxides have attracted attention in supercapacitors research, but their slow reaction kinetics and poor long-cycle performance limit their potential application. In this study, MnCo2O4 micro-flowers with a hierarchical structure were prepared. MnCo2O4-MF exhibits multiple metal valence states and a unique hierarchical structure, which provide more electrochemical active sites and improve cycling stability.