Phytic acid treated nickel-iron hydroxide promotes efficient electrocatalytic overall water splitting

It is highly urgent to develop efficient and stable non-precious metal electrocatalysts for water splitting. Here, we have successfully prepared a phytic acid (PA)-treated NiFe layered double hydroxide (LDH) catalyst. NiFe-LDH(PA) exhibits excellent catalytic activity towards the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER), and overall water splitting (OWS) (eta 10 = 112 mV and eta 100 = 198 mV for the HER, eta 100 = 260 mV for the OER, and 1.69 V for OWS @ 100 mA cm-2) as well as remarkable stability during long-term testing (100 h for the HER, 90 h for the OER, and 100 h for OWS). The PA treatment accelerates the catalytic kinetics of NiFe-LDH(PA) and exposes more active sites, leading to enhanced charge transfer. This work demonstrates the significant potential of organic small molecules in modifying the performance of conventional catalysts. Phytic acid-treated NiFe-LDH exposes more active sites and can improve the electrocatalytic performance in water splitting.