Figure 8. The reaction mechanism of Zn//ZMOP-4/PCNTs-6 ZISC is
as follows: (a) GCD curve of Zn//ZMOP-4/PCNTs-6 ZISC under different
charging/discharging states (current density is 0.2 A
g-1); (b and c) XRD patterns of ZMOP-4 cathode and
PCNT-6 anode at different charging/discharging states.
The seven major characteristic peaks of the typical
α-MnO2 are distinctly described. And comparing the XRD
patterns of the samples, the crystal framework of the ZMOP-4 electrode
materials isn’t affected by charging-discharging process can be found.
The XRD pattern almost shows non-change during the charging-discharging
procedure, which indicates that the tunneling crystal structure of
ZMOP-4 nanowires is reversible and stable during the ion
insertion/extraction process. Meanwhile, it also can support the good
cyclic stability of ZISCs. Similarly, as for PCNTs anode (Figure
8c ), there is no new crystal structure appearing, which also can
indicate the excellent stability of ZISCs.