Transition-Metal Oxides/Carbides@Carbon Nanotube Composites as Multifunctional Electrocatalysts for Challenging Oxidations and Reductions |
| |
Authors: | Xiaolin Xing Dr Rongji Liu Kecheng Cao Prof Ute Kaiser Prof Carsten Streb |
| |
Institution: | 1. Institute of Inorganic Chemistry I, Ulm University, Ulm, 89081 Germany;2. Central Facility of Electron Microscopy for Materials Science, Ulm University, Ulm, 89081 Germany |
| |
Abstract: | The rapid development of renewable-energy technologies such as water splitting, rechargeable metal–air batteries, and fuel cells requires highly efficient electrocatalysts capable of the oxygen-reduction reaction (ORR) and the oxygen-evolution reaction (OER). Herein, we report a facile sonication-driven synthesis to deposit the molecular manganese vanadium oxide precursor Mn4V4O17(OAc)3]3− on multiwalled carbon nanotubes (MWCNTs). Thermal conversion of this composite at 900 °C gives nanostructured manganese vanadium oxides/carbides, which are stably linked to the MWCNTs. The resulting composites show excellent electrochemical reactivity for ORR and OER, and significant reactivity enhancements compared with the precursors and a Pt/C reference are reported. Notably, even under harsh acidic conditions, long-term OER activity at low overpotential is reported. In addition, we report exceptional activity of the composites for the industrially important Cl2 evolution from an aqueous HCl electrolyte. The new composite material shows how molecular deposition routes leading to highly active and stable multifunctional electrocatalysts can be developed. The facile design could in principle be extended to multiple catalyst classes by tuning of the molecular metal oxide precursor employed. |
| |
Keywords: | electrocatalysis electrochemistry organic–inorganic hybrid composites oxygen evolution polyoxometalates |
|
|