SUPPORT EFFECT ON THE STRUCTURE AND PROPERTIES OF MANGANESE OXIDE ELECTRODE MATERIALS

Abstract

The composite electrode material of manganese oxide supported on poly glucose (PGS) was prepared by using KMnO4 as manganese source. In order to study the influence of the support on the structure and properties of the composite electrode materials, the changes of the composition of the composite electrode materials were investigated in different weight ratio of KMnO4/PGS (3:1, 3:3, 3:5, 3:7, 3:9). The characterization results of XRD, Raman special and XPS indicated the composition of manganese oxides was greatly influenced by the content of PGS. When the PGS content is lower, the composition of manganese oxide in hybrid material is single-component oxide (MnOOH or Mn3O4). With the increasing PGS content, a mixture of Mn3O4 and MnCO3 was observed, furthermore proportion of MnCO3 in mixture also increased, and up to higher PGS content (KMnO4/PGS=3:9), single-component MnCO3 was founded on hybrid material. In addition, the change of composition of hybrid materials also led to an obvious difference in electrochemical performance. With the increase of PGS content, the specific capacitance of hybrid materials increases firstly, and reaches the maximum with the weight ratio of KMnO4/PGS equal to 3:3, and then gradually decreases. This was attributed to the higher electrochemical performance of Mn3O4 than that of MnOOH and MnCO3.

Keywords

• manganese oxides
• support effects
• poly glucose
• composite electrode material
• electrochemistry