Effects of Reaction Temperature on Microstructure and Advanced Pseudocapacitor Properties of NiO Prepared via Simple Precipitation Method

Qiangqiang Sun,Shujuan Bao

doi:10.5101/nml.v5i4.p289-295

Abstract

Morphology-controlled synthesis and large-scale self-assembly of nanoscale building blocks into complex nanoarchitectures is still a great challenge in nanoscience. In this work, various porous NiO nanostructures are obtained by a simple ammonia precipitation method and we find that the reaction temperature has a significant impact on their microstructures. Nanoflowers and nanoflakes have been obtained at 0°C and 50°C, while, weakly self-assembly nanoflowers with nanoflakes are formed at 20°C. In order to understand the process-structure-property relationship in nanomaterial synthesis and application, the as-prepared NiO is used as supercapacitor electrode materials, and evaluated by electrochemical measurement. The experimental results indicate that the material obtained at lower temperature has higher pseudocapacitance, the specific capacitance of 944, 889 and 410 F/g are reached for the materials prepared at 0°C, 20°C and 50°C and further calcined at 300°C, respectively. While the material obtained at higher temperature has excellent rate capacity. This offers us an opportunity searching for exciting new properties of NiO, and be useful for fabricating functional nanodevices.

Highlights

In recent years, nanomaterials, with different dimensionalities and morphologies attract much attention due to their novel and unexpected properties
We have carefully investigated the influence of reaction temperature on the microstructure of products formed in ammonia precipitation and given a rational proposal about their forming mechanism
The results indicate that the sample synthesized at 0°C and further annealed at 300°C has a highest specific capacitance of 944 F/g at the current density of 1 A/g, its rate capacity is worse, which is closely related with its textural properties

Summary

Introduction

Nanomaterials, with different dimensionalities and morphologies attract much attention due to their novel and unexpected properties. The researchers found that the microstructure of NiO formed by ammonia precipitation can be tailored by reaction condition. The results indicate that the sample synthesized at 0°C and further annealed at 300°C has a highest specific capacitance of 944 F/g at the current density of 1 A/g, its rate capacity is worse, which is closely related with its textural properties.

Results

Conclusion