Atomically dispersed nickel–nitrogen–sulfur species anchored on porous carbon nanosheets for efficient water oxidation
© Alessandro Licata/Getty
A precisely positioned quintet of nickel, sulfur and nitrogen atoms could pave the way to low-cost materials for the solar-powered production of hydrogen fuel.
Water-splitting photoelectrocatalysts use sunlight to produce readily storable and transportable hydrogen fuel. Water splitting also generates oxygen via the oxygen evolution reaction (OER), but high-performing OER catalysts typically use rare and expensive metals.
Recent research into alternative, earth-abundant OER catalyst materials has highlighted the catalytic properties of single nickel atoms bonded to four nitrogen atoms within a carbon nanosheet. However, theoretical studies have suggested the strong electron-withdrawing nature of nitrogen atoms might slow the reaction.
Now, an international team, which included researchers from the Advanced Institute for Materials Research at Tohoku University, has shown that swapping a nitrogen atom for a sulfur atom leads to significantly higher OER performance. The five-atom nickel–nitrogen–sulfur structure even out-performed the state-of-the-art iridium/carbon OER catalyst.
- Nature Communications 10, 1392 (2019). doi: 10.1038/s41467-019-09394-5