 The researchers developed a novel multi-layer architecture consisting of nickel-cobalt-layered double-hydroxides, NiClDH, and cobalt-phosphates, CoH, to create a self-supporting electrode, CoH-slash-NECO at NF. This structure showed excellent catalytic performance for both hydrogen evolution reaction, HER, and oxygen evolution reaction, OR, requiring only over potentials of 180 mV and 350 mV to deliver 100 mA Cm2, resulting in a cell potential of 1.76 V for overall water splitting at the corresponding current density. Furthermore, the prepared CoH-slash-NECO at NF has long-term stability against 500 mA Cm2 and exhibited a trend of increased activity, which could be attributed to the formation of new structures and strong bonds between layers. This article was authored by Yan Kai Huang, Su Dong Song, Sebao Chen, and others.