Lu, XunyuTan, XinZhang, QingranDaiyan, RahmanPan, JianChen, RuiTahini, H. A.Wang, Da-WeiSmith, SeanAmal, Rose2020-06-042050-7496http://hdl.handle.net/1885/204802The storage and conversion of the surplus electricity generated by photovoltaic (PV) cells call for efficient electrochemical devices, such as water electrolyzers and metal–air batteries. Catalyst materials are normally the key in determining the efficiency of these devices, as the electrochemical processes involved are normally sluggish in reaction kinetics. Herein, we found that by encapsulating Ni, Co and Fe alloyed cores inside graphitic carbon shells (NiCoFe@C), a versatile catalyst material can be obtained, showing decent activity towards the oxygen evolution reaction (OER), oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER). The encapsulation of the NiCoFe alloyed core induces the electronic structure change of the outer graphitic carbon shell, which tunes the binding strength of reaction intermediates thereby improving the catalytic activity.application/pdfen-AU© The Royal Society of Chemistry 2019201910.1039/c9ta01723b2019-12-19