Facile construction of heterostructural Ni3(NO3)2(OH)4/CeO2 bifunctional catalysts for boosted overall water splitting

Interface engineering has aroused vitally widespread concern since it could be an effective strategy for exploring high-performance and low-cost water oxidation electrocatalysts. Herein, we report a hetero-structured Ni3(NO3)2(OH)4/CeO2/NF (NNO/CeO2/NF) electrode, exhibiting superior performance owning to the NO3− anion substitution for the OH− in nickel hydroxide to form Ni3(NO3)2(OH)4, together with its interface synergy with ceria. In alkaline solution, the NNO/CeO2/NF electrocatalyst could catalyze the OER with an overpotential of 330 mV to approach 50 mA cm−2. Also, it needs only an overpotential of 120 mV to reach 10 mA cm−2 for HER. Additionally, when a standard two-electrode water electrolyzer is fabricated by employing NNO/CeO2/NF as both the cathode and anode, it can generate 10 mA cm−2 at 1.64 V and operate steadily without performance degradation after 25 h. This research provides a novel perspective for reasonable design of advanced catalytic materials with improvements in the field of electrocatalysis.