Co2P2O7 Microplate/Bacterial Cellulose-Derived Carbon Nanofiber Composites with Enhanced Electrochemical Performance.

Likkhasit Wannasen,Supree Pinitsoontorn,Wiyada Mongkolthanaruk,Ekaphan Swatsitang,Prasert Pavasant

doi:10.3390/nano11082015

Abstract

Nanocrystalline Co2P2O7 and carbon nanofiber (Co2P2O7/CNFs) composites with enhanced electrochemical performance were obtained by calcination after a hydrothermal process with NH4CoPO4∙H2O/bacterial cellulose precursors under an argon atmosphere. SEM images showed that the CNFs were highly dispersed on the surfaces of Co2P2O7 microplates. The diagonal size of the Co2P2O7 plates ranged from 5 to 25 µm with thicknesses on a nanometer scale. Notably, with the optimal calcining temperature, the Co2P2O7/CNFs@600 material has higher specific micropore and mesopore surface areas than other samples, and a maximal specific capacitance of 209.9 F g−1, at a current density of 0.5 A g−1. Interestingly, CNF composite electrodes can enhance electrochemical properties, and contribute to better electrical conductivity and electron transfer. EIS measurements showed that the charge–transfer resistance (Rct) of the CNF composite electrodes decreased with increasing calcination temperature. Furthermore, the Co2P2O7/CNF electrodes exhibited higher energy and power densities than Co2P2O7 electrodes.

Highlights

IntroductionHybrid Li–ion batteries and supercapacitors have an important role in electric vehicles due to their high energy and power densities, respectively [4,5]
It should be noted that the derivative thermogravimetry (DTG) peak for the evaporation of water molecule occurs at different positions between
Co2 P2 O7 /carbon nanofibers (CNFs) composites were successfully prepared via calcination after a hydrothermal process employing NH4 CoPO4 ·H2 O/bacterial cellulose (BC)

Summary

Introduction

Hybrid Li–ion batteries and supercapacitors have an important role in electric vehicles due to their high energy and power densities, respectively [4,5]. Their use has increased in various applications because of their high power density, fast charge–discharge time and long life cycles compared to other energy storage devices [6]. The electrode material of a supercapacitor consists of activated carbon, which can be converted into many forms such as buckyballs, nanotubes, nanobuds, and nanofibers. This is because of its large specific surface area, high porosity, high conductivity, high thermal stability and low cost [9,10,11,12]. Graphene oxide loaded in a poly vinylidene fluoride–co–hexafluoropropylene by the innovative preparation methods

Methods

Results

Conclusion