Palladium nanoparticles grown on beta-Mo2C nanotubes as dual functional electrocatalysts for both oxygen reduction reaction and hydrogen evolution reaction

Developing efficient dual functional electrocatalysts for both oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) is critical for boosting the performance of fuel cells and metal air batteries, as well as production of clean and sustainable energy source. Herein, Pd nanoparticles grown on Mo2C nanotubes were prepared as dual functional electrocatalysts for both ORR and HER. A series of samples with different Pd loadings were fabricated, while the morphology and the structural features were well examined by transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Interestingly, both the ORR activity and HER activity first increased then decreased with the increasing of Pd loading, and the sample of Mo2C-Pd-9% exhibited the best performance among the series, superior than commercial Pd/C in both ORR and HER tests. Furthermore it also exhibited markedly higher long-term stability than Pd/C for both electrocatalytic reactions. The results may shed light on rational design of novel bifunctional electrocatalysts in the renewable energy field. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.