Nanoarray-structured nitrogen-doped graphite foil as the support of NiFe layered double hydroxides for enhancing oxygen evolution reaction

An ideal carbon support, nanoarray-structured nitrogen-doped graphite foil (NNGF), is facilely prepared via a nitrogen plasma procedure of commercial graphite foil (GFL). After plasma treatment, NNGF owns both the bulk layer of graphite inherited from GFL and surface layer of nanoarray-structured defect-rich N doped carbon. Nanometer-sized NiFe layered double hydroxides (NiFe LDH), as an example, are electrodeposited onto NNGF for direct utilization as an OER electrode. Due to the remained graphite layer, the composite electrode is highly conductive; owing to the strong interaction between N dopants and LDH sheets, the charge transfer is dramatically enhanced; meanwhile the diffusion of liquid reactants and gas products during electrocatalysis is also facilitated by the nanoarray structure. As expected, this hybrid NiFe LDH/NNGF electrode exhibits a low overpotential of 0.191 V at 10 mA cm(-2). Such nanoarray-structured carbon material is promising to be a universal support for other active species (e.g. NiCo LDH).