Ni, WeiyanWang, TengSchouwink, Pascal AlexanderChuang, Yu-ChunChen, Hao MingHu, Xile2020-05-102020-05-102020-05-102020-04-2810.1002/anie.201916314https://infoscience.epfl.ch/handle/20.500.14299/168681WOS:000528892800001The hydroxide-exchange membrane fuel cell (HEMFC) is a promising energy conversion device. However, the development of HEMFC is hampered by the lack of platinum-group-metal-free (PGM-free) electrocatalysts for the hydrogen oxidation reaction (HOR). Now, a Ni catalyst is reported that exhibits the highest mass activity in HOR for a PGM-free catalyst as well as excellent activity in the hydrogen evolution reaction (HER). This catalyst, Ni-H-2-2 %, was optimized through pyrolysis of a Ni-containing metal-organic framework precursor under a mixed N-2/H-2 atmosphere, which yielded carbon-supported Ni nanoparticles with different levels of strains. The Ni-H-2-2 % catalyst has an optimal level of strain, which leads to an optimal hydrogen binding energy and a high number of active sites.Chemistry, MultidisciplinaryChemistryalkaline fuel cellselectrocatalystshydrogen evolution reactionhydrogen oxidation reactionstrain effectoxygen reductionalkaline medialigandelectrocatalystsadsorptionensembleshelltext::journal::journal article::research article