Unlocking Supercapacitor Energy Storage Potential

The key to enhancing supercapacitor system performance lies in innovatively integrating novel electrode materials seamlessly into various structures. Here, we present a method for directly preparing a nanorod array containing crystalline/amorphous CuO/MnO2−x. This reconfigured heterostructure enhances the electrochemical active MnO2 content. The nanorod array serves as an efficient capacitive anode, which can be easily prepared through low-potential electrochemical activation. The resulting structure spontaneously forms a p-n heterojunction, generating an internal electric field that greatly facilitates the charge transfer process. The internal electric field combined with the crystalline/amorphous structure allows this composite material to achieve a large capacitance of 1.0 F·cm−2 at 1.0 mA·cm−2, with an ultra-high rate performance of approximately 85.4% at 15 mA·cm−2, and maintains 92.4% stable cycling performance after 10,000 cycles. Theoretical calculations indicate that the presence of the heterojunction optimizes the electronic structure of this composite material, thereby enhancing conductivity and optimizing the adsorption energy of OH−. This work provides new insights for the rational design of heterostructured nanostructures that have great potential in energy storage applications.

1. Introduction

1. Supercapacitors (SCs) have higher power density and longer cycle life compared to lithium-ion batteries, but there is still room for improvement in energy density.

2. Manganese oxides (MnOx) have garnered significant attention as pseudocapacitive materials due to their ability to exhibit various Mn(x+) oxidation states in redox reactions.

3. However, the main bottleneck of MnOx is its poor conductivity, which limits its application in supercapacitors.

4. Interface engineering is a widely recognized concept used to enhance electrode activity.

2. Experimental Section

This section details the chemicals and materials used in the experiments, material preparation methods, material characterization methods, electrochemical measurements, and electrochemical calculation methods.

3. Results and Discussion

1. The researchers prepared a nanorod array of crystalline CuO/amorphous MnO2−x using a direct method.

2. This heterostructure significantly enhances the electrochemical active content of MnO2.

3. The electrochemical measurement results show that this nanorod array exhibits excellent capacitance performance.

Density functional theory (DFT) calculations further reveal the electronic structure and charge distribution characteristics of this heterostructure.

4. Illustrated Guide

5. Conclusion

• This study successfully designed and prepared a three-dimensional crystalline CuO/amorphous MnO2−x heterostructured nanorod array as an efficient capacitive anode.

• This design significantly enhances the electrochemical activity of MnO2 and greatly improves the performance of supercapacitors.

• This study provides new ideas and methods for the design of supercapacitor electrode materials.

The research findings in this document are of great significance for promoting the performance enhancement of supercapacitor systems and provide new directions for the design and preparation of novel electrode materials.

This article is provided by the Hydrogen Energy Research Assistant.

Original link:

https://www.sciopen.com/article/10.1007/s12274-024-6577-6

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