Nonstoichiometric Cu0.6Ni0.4Co2O4 Nanowires as an Anode Material for High Performance Lithium Storage.

Quanbing Liu,Ningyi Jiang,Yufa Feng,Junhao Li,Hao Li,Jinyun Liao

doi:10.3390/nano10020191

Abstract

Transition metal oxide is one of the most promising anode materials for lithium-ion batteries. Generally, the electrochemical property of transition metal oxides can be improved by optimizing their element components and controlling their nano-architecture. Herein, we designed nonstoichiometric Cu0.6Ni0.4Co2O4 nanowires for high performance lithium-ion storage. It is found that the specific capacity of Cu0.6Ni0.4Co2O4 nanowires remain 880 mAh g−1 after 50 cycles, exhibiting much better electrochemical performance than CuCo2O4 and NiCo2O4. After experiencing a large current charge and discharge state, the discharge capacity of Cu0.6Ni0.4Co2O4 nanowires recovers to 780 mAh g−1 at 50 mA g−1, which is ca. 88% of the initial capacity. The high electrochemical performance of Cu0.6Ni0.4Co2O4 nanowires is related to their better electronic conductivity and synergistic effect of metals. This work may provide a new strategy for the design of multicomponent transition metal oxides as anode materials for lithium-ion batteries.

Highlights

Lithium-ion batteries (LIB) have many advantages, such as high energy density, excellent cycle stability, no memory effect, and so on [1]
The transition metal oxide Co3O4 used as a promising anode material for lithium-ion batteries, first reported by Poizot [3] in 2000, has attracted extensive interest of researchers with 890 mAh g−1 theoretical capacity, which is much higher than commercial graphite (372 mAh g−1)
Different from lithium intercalation mechanism of graphite, Co3O4 is based on a conversion reaction as anode materials transforms into metallic cobalt, with great volume expansion and metal reunion during lithiation/deithiation [4]

Summary

Introduction

Lithium-ion batteries (LIB) have many advantages, such as high energy density, excellent cycle stability, no memory effect, and so on [1]. They are widely used in many fields, such as electronic products, electric vehicles, and energy storage system, which have greatly improved modern humans’ lives [2]. Lou [26] synthesized NiCo2O4 complex hollow spheres as anode material in lithium-ion battery and its specific capacity was 1400 mAh g−1 at 150 mA g−1 with great cycling stability. We report nonstoichiometric Cu0.6Ni0.4Co2O4 nanowires, which can be regarded as a composite of CuCo2O4 and NiCo2O4, as an anode material in lithium-ion battery. After 50 cycles, the specific capacity of Cu0.6Ni0.4Co2O4 nanowires remain 880 mAh g−1 and the coulombic efficiency is approximately 100%

Synthesis of Anode Materials

Characterizations

Conclusions