Mesoporous ternary oxides (NiCo2O4, CuCo2O4, MnCo2O4) and quaternary mixed oxides
(CuNiCo2O4, CuMnCo2O4, MnNiCo2O4) are synthesized through a urea and surfactantaided co-precipitation method, followed by a post-thermal treatment at 500 ºC. All
materials are characterized by means of XRD, TEM-SAED, N2 -sorptiometry and FTIR
spectrometry. All samples have a mesoporous structure. The CuCo2O4 sample consists of
CuO (monoclinic) and CuCo2O4 spinel structure and MnCo2O4 consisted of α-MnO2 and
MnCo2O4 spinels structure. The supercapacitor performances of quaternary nano-oxides
are examined in comparison with their corresponding ternary oxides by cyclic
voltammetry (CV), charge-discharge (CD) and electrochemical impedance spectroscopy
(EIS) measurements. Both CuCo2O4 and MnCo2O4 electrodes exhibit excellent
supercapacitor performances that show a high specific capacitance of 915 F g-1
and 690 F
g
-1
at 56 mA g
-1
, respectively. The quaternary mixed oxides have low performance. The
CuCo2O4 and MnCo2O4 electrodes show capacitance retention of 99 and 98.8 %,
respectively which explain their superior cycle stability. |
