Polycrystalline SnSx nanofilm enables CO2 electroreduction to formate with high current density

Polycrystalline SnSx (p-SnSx) nanofilms are capable of yielding formate with a maximum faradaic efficiency of 97% and high stability over 50 h. Moreover, when tested in a membrane electrode assembly cell, p-SnSx has a high faradaic efficiency in a broad partial current density range (100–420 mA cm−2) for formate production.