Approaches to structural and compositional modifications of non-noble metal oxygen reduction reaction and oxygen evolution reaction electrocatalysts are essential for advanced rechargeable Zn-air batteries (ZABs). In this work, three-dimensional (3D) porous carbon nanotube (CNT) microsphere prepared by spray pyrolysis are used as conductive carbon framework. MnO2 and Fe2O3 nanorods are uniformly deposited on rationally designed CNT microsphere via a two-step bottom-up processing; through the formation of 3D porous architecture, electron transfer and mass transport can be facilitated. Due to the synergetic effect of uniformly deposited MnO2 and Fe2O3 nanorods and 3D porous architecture of CNT framework, MnO2-Fe2O3/CNT exhibited superior oxygen reduction/evolution catalytic activities under alkaline media comparing to Pt/C-RuO2. Moreover, as a bifunctional electrocatalyst for ZABs, MnO2-Fe2O3/CNT delivered high power density of 253 mW cm−2, specific capacity of 802 mA h g−1, and low polarization potential difference, as well as long-term cycling stability up to 3600 min.
Bibliographical noteFunding Information:
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2019R1A2C2088047 and 2020R1A4A2002854).
© 2021 Elsevier B.V.
- 3D porous architectures
- Bifunctional electrocatalysts
- CNT microspheres
- Spray pyrolysis
- Zn-air batteries
ASJC Scopus subject areas
- General Chemistry
- Environmental Chemistry
- General Chemical Engineering
- Industrial and Manufacturing Engineering