Co/Co3O4 nanoparticles embedded into thin O-doped graphitic layer as bifunctional oxygen electrocatalysts for Zn-air batteries
| Autor: | Shuai Tang, Xuefeng Zhang, Gaowu Qin, Jianmin Wang, Luhan Wei, Song Li, Qinghua Liang, Xi Yang, Sichen Jiao, Zhen Zhao, Feng Cao |
|---|---|
| Rok vydání: | 2022 |
| Předmět: |
Materials science
General Chemical Engineering Doping chemistry.chemical_element Nanoparticle 02 engineering and technology General Chemistry Overpotential 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Oxygen Industrial and Manufacturing Engineering Cathode 0104 chemical sciences law.invention chemistry.chemical_compound chemistry Chemical engineering law Environmental Chemistry 0210 nano-technology Bifunctional Carbon Power density |
| Zdroj: | Chemical Engineering Journal. 427:130931 |
| ISSN: | 1385-8947 |
| Popis: | Developing low-cost and efficient oxygen electrocatalysts for oxygen reduction and evolution reaction (ORR&OER) is critical for various energy conversion technologies. Herein, we report an arc discharge strategy coupled with an controllable oxidation to prepare Co/Co3O4 nanoparticles confined in ultrathin O-doped graphitic carbon layer (Co/Co3O4@ODGC) as highly active bifunctional oxygen electrocatalysts for Zn-air batteries (ZABs). The resultant Co/Co3O4@ODGC shows an impressive ORR performance with a half-wave potential of 0.80 V in 0.1 M KOH. It also exhibits remarkable OER performance with a small overpotential of 300 mV to reach a current density of 10 mA cm−2. Both experimental studies and theoretical calculations indicate that the high ORR and OER activities are attributed to the synergistic electronic effect between the Co/Co3O4 heterostructures and ultrathin O-doped graphitic layer (~1.5 nm). Particularly, the electron redistribution in graphitic layer caused by O-doping and carbon defects significantly decreases the energy barrier for oxygen adsorption/desorption. More attractively, the as-constructed ZABs with Co/Co3O4@ODGC cathode show an impressive open voltage (1.60 V), a high power density of 107 mW cm−2, and good stability without nearly no performance decay for 40 h at 2.0 mA cm−2. This work provides both fundamental understanding and easy strategy for developing the efficient bifunctional oxygen electrocatalysts for high performance metal-air batteries. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect