TY - JOUR EP - 1304 AV - public VL - 11 SP - 1295 Y1 - 2018/02/14/ TI - Tunable Bifunctional Activity of MnxCo3-xO4 Nanocrystals Decorated at Carbon Nanotubes for Oxygen Electrocatalysis N1 - This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article?s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ SN - 1864-564X UR - http://doi.org/10.1002/cssc.201800049 ID - discovery10044685 N2 - Noble-metal free electrocatalysts are attractive for cathodic oxygen catalysis in alkaline membrane fuel cells, metal-air batteries and electrolysers. However, much of the structure-activity relationship is poorly understood. Here, comprehensive development of manganese cobalt oxide/nitrogen-doped multi-walled carbon nanotube hybrids (MnxCo3-xO4@NCNTs) is reported for highly reversible oxygen reduction and evolution reactions (ORR and OER). The hybrid structures are rationally designed by fine control of surface chemistry and synthesis conditions, including: tuning of functional groups at surfaces, congruent growth of nanocrystals with controllable phases and particle sizes, and ensuring strong coupling across catalyst-support interfaces. Electrochemical tests reveal distinctly different oxygen catalytic activities among the hybrids, MnxCo3-xO4@NCNTs. A nanocrystalline MnCo2O4@NCNTs (MCO@NCNTs) hybrid shows superior ORR activity, with a favourable onset potential and a high current density response, equivalent to the commercial Pt@C standard. Moreover, the hybrid structure exhibits tuneable and durable catalytic activities for both ORR and OER, with a lowest overall potential of 0.93 V. It is clear that the long-term electrochemical activities can be ensured by rational design of hybrid structures from the nanoscale. KW - Bifunctional electrocatalyst KW - Carbon nanotubes KW - Manganese cobalt oxide KW - Oxygen reduction reaction KW - oxygen evolution reaction A1 - Zhao, T A1 - Gadipelli, S A1 - He, G A1 - Ward, M A1 - Do, D A1 - Zhang, P A1 - Guo, Z JF - ChemSusChem ER -