Flower-like ZnCo2O4 nanowires: toward a high-performance anode material for Li-ion batteries

Abstract

Rising interest in lightweight, thin, and flexible energy storage devices has led to numerous studies that aim to fulfill the special needs of next-generation, high-performance flexible electronics. In this study, flowerlike ZnCo 2 O 4 nanowires are fabricated by a facile hydrothermal method followed by heat treatment in air at 400 C. The structures and morphologies of as-prepared ZnCo 2 O 4 nanowires are characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The data indicate that the as-synthesized flower-like ZnCo 2 O 4 nanowires are approximately 2.5 mm in length and range from 50 nm to 150 nm in diameter. The as-prepared flower-like ZnCo 2 O 4 nanowire products are evaluated as anode materials for lithium-ion battery application. The special structural features of ZnCo 2 O 4 nanowires, including high coating uniformity, high coating density, and porous architecture, exert a significant effect on the electrochemical performance of the nanowires. The discharge capacity of ZnCo 2 O 4 flowerlike nanowires can reach first discharge capacity at 1430 mA h g À1 to $900 mA h g À1 after 50 discharge-charge cycles at a current density of 200 mA g À1 , indicating its potential applications for next-generation, high-performance flexible electronics. High battery performance is mainly attributed to the dense and porous nanowire structures composed of interconnected ZnCo 2 O 4 nanoparticles, which provide good electrolyte diffusion and large electrode-electrolyte contact area while reducing volume change during the charge-discharge process. The fabricated electrode can be used to light up commercial light emitting diodes.

Facile synthesis of mesoporous ZnCo2O4 coated with polypyrrole as an anode material for lithium-ion batteries

“…The weak peak at 1.89 V might be related to Li þ insertion into the structure of ZnCo 2 O 4 and the interfacial storage [15,32,33]. The reverse scan is featured by two peaks at 1.66 and 2.13 V, which can be associated with the oxidation of Zn to ZnO and Co to Co 3 O 4 shown in Equations (3)e(5) [34,35]. In the second and third cycle, it can be observed that the reduction peak is gradually moved to about 1.18 V and becomes much broader, which is different from the irreversible electrochemical reaction during the first discharge cycle.…”

Facile synthesis of MgCo2O4 nanowires as binder-free flexible anode materials for high-performance Li-ion batteries

“…Apparently, the above results that the improvement in lithium storage properties should attribute to the nanostructured morphology, providing a high-specific surface area to add the contact area between active electrode materials and electrolyte. The high contact area can MgCo 2 O 4 nanowire *940 mAh g -1 at 2.5 A g -1 *550 mAh g -1 at 10 A g -1 This work NiCo 2 O 4 nanoflake *880 mAh g -1 at 0.5 A g -1 *540 mAh g -1 at 2 A g -1 Zheng et al (2015) MnCo 2 O 4 microspheres *940 mAh g -1 at 0.2 A g -1 *400 mAh g -1 at 2.7 A g -1 Fu et al (2014) Ellipsoidal MnCo 2 O 4 *950 mAh g -1 at 0.1 A g -1 *820 mAh g -1 at 0.4 A g -1 Huang et al (2014) NiCo 2 O 4 microspheres *550 mAh g -1 at 0.8 A g -1 *390 mAh g -1 at 1.6 A g -1 Li et al (2013) ZnCo 2 O 4 microspheres *970 mAh g -1 at 0.1 A g -1 *400 mAh g -1 at 5 A g -1 Hu et al (2013) ZnCo 2 O 4 nanowires *1020 mAh g -1 at 0.2 A g -1 *340 mAh g -1 at 0.8 A g -1 Mohamed et al (2013) ZnCo 2 O 4 flower-like *1200 mAh g -1 at 0.1 A g -1 *880 mAh g -1 at 1 A g -1 Chen et al (2015) Nano-phase-CuCo 2 O 4 *820 mAh g -1 at 0.1 A g -1 *380 mAh g -1 at 0.752 A g -1 Sharma et al (2007b) FeCo 2 O 4 nanoflakes *1570 mAh g -1 at 0.2 A g -1 *1220 mAh g -1 at 0.8 A g -1 Mohamed et al (2014) ZnCo 2 O 4 nanostructure *1015 mAh g -1 at 0.5 A g -1 *606 mAh g -1 at 1 A g -1 Song et al (2014) Porous ZnCo 2 O 4 *1550 mAh g -1 at 0.1 A g -1 *500 mAh g -1 at 5 A g -1 Hao et al (2015) Flower-like MnCo 2 O 4 *330 mAh g -1 at 0.05 A g -1 *180 mAh g -1 at 0.2 A g -1 Wu et al (2015) MnCo 2 O 4 nanowire *820 mAh g -1 at 0.2 A g -1 *340 mAh g -1 at 1 A g also provide more active sites for lithium-ion insertion/extraction. In addition, during the first discharge, Mg metal atoms form inactive MgO, which can inhibit volume variations effectively during the electrochemical reaction.…”

Urea-assisted solvothermal synthesis of monodisperse multiporous hierarchical micro/nanostructured ZnCo2O4 microspheres and their lithium storage properties

“…According to previous papers, the entire electrochemical process can be explained as follows [35,36]:…”