A coordination polymer-derived Co3O4/Co–N@NMC composite material as a Zn–air battery cathode electrocatalyst and microwave absorber. Issue 21 (18th October 2018)

• Record Type: Journal Article
• Authors: Wang, Yaqin; Xu, Xinxin; Liu, Luyao; Chen, Jin; Shi, Guimei
• Is Part Of: Dalton transactions. Volume 48:Issue 21(2019)
• Page Start: 7150
• Page End: 7157
• Publication Date: 2018-10-18
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c8dt03792b
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : With a one-dimensional coordination polymer as a precursor, a Co–N active center-rich Co3 O4 -based bi-functional electrocatalyst was synthesized as a cathode for Zn–air batteries. Abstract : Zn–air batteries, promising energy storage equipment with high energy density, light weight and a compact structure, are a perfect power source for electric vehicles. For a Zn–air battery, the activity of the air cathode electrocatalyst plays an important role in its performance. Here, employing a coordination polymer as a precursor, a composite material built from Co3 O4 and Co–N active centres with nitrogen-doped mesoporous carbon as a matrix has been synthesized successfully. This composite material possesses outstanding activity and stability in the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) processes. It possesses a small half-wave potential (ORR1/2 = 0.786 V) and low overpotential (OER10 = 1.575 V) for the ORR and OER, respectively. With this composite material as an air cathode electrocatalyst, a rechargeable Zn–air battery was assembled successfully. During the discharge process, the maximum power density of this Zn–air battery is 122 mW cm −2 at 0.76 V. The specific capacity of this battery is 505 mA h g −1 at 25 mA cm −2 . The voltage gap between the charge and discharge processes is only 0.744 V at 10 mA cm −2 and 1.308 V at 100 mA cm −2 . This rechargeable battery also shows promising stability after long-term charge–discharge experiments. Furthermore, the composite material also exhibits outstanding microwave adsorption properties. Its maximum reflection loss (RL) arrives at −13.9 dB with a thickness of only 1.0 mm. Thus, we find that coordination polymers are an ideal precursor for Zn–air battery cathode electrocatalysts and microwave absorbers.