Construction of Interface-Engineered Coral-like Ni2P@CeO2 Hybrid Nanoarrays to Boost Electrocatalytic Hydrogen Evolution Performance in alkaline water/seawater electrolytes

Fabricating a functional heterogeneous interface to enhance the catalytic performance is quite significant for developing high-efficient electrocatalysts. Herein, we designed a coral-like Ni 2 P@CeO 2 hybrid nanoarrays on nickel foam via selective-phosphorization of Ni(OH) 2 @CeO 2 . Benefiting from CeO 2 as the “electron pump”, it leads to electrons transfer from Ni 2 P to CeO 2 side, and induces the electrons redistribution in interface boundary, thereby optimizing the H* adsorption free energy in HER process. As proposed, owing to the superior affinity to oxygen-containing species of CeO 2 , the H 2 O molecule will preferentially adsorb on CeO 2 side, and easily decompose into OH* and H* with lower energy barrier. Subsequently, benefiting from the lower H* adsorption free energy of P sites, the generated H* will transfer to Ni 2 P side through spillover process. Contributing to the synergistic effect of double-active sites, the Ni 2 P@CeO 2 /NF electrode exhibits brilliant catalytic performance for HER with 62 mV to attain 10 mA/cm 2 and exceptional durability over 100 h in 1 M KOH solution under ~ 100 mA/cm 2 . Meanwhile, attributing to the similar interface electrons redistribution effect, the precursor Ni(OH) 2 @CeO 2 /NF also displays excellent OER electrocatalytic performance, it only requires 229 mV to arrive 10 mA/cm 2 , even better than benchmark RuO 2 . Hence, the assembled Ni(OH) 2 @CeO 2 /NF || Ni 2 P@CeO 2 /NF system only needs 1.53 V to achieve 10 mA/cm 2 in basic solution. Moreover, the electrolyzer also presents brilliant electrocatalytic activity and stability in natural seawater alkaline electrolyte with higher reserves on earth. This research offers a novel insight to enhance the catalytic properties of TMPs materials for hydrogen production.