Self-Supported Ni/NiSPx Microdendrite Structure for Highly Efficient and Stable Overall Water Splitting in Simulated Industrial Environment

The design and development of non-noble metal-based bifunctional electrocatalysts for hydrogen production from catalytic electrolysis of water in industrial environments is very important for the application of hydrogen energy in commercial fields. Here, we report the use of a simple one-step electrodeposition method to prepare amorphous NiSPx microdendritic structure catalytic electrodes with small amount of Ni on nickel foam. The optimal electrocatalyst Ni/NiSPx requires only low overpotentials of 46 and 231 mV for HER and OER at the current density of 10 mA·cm–2, respectively. Even at the commercially practical current density of 1000 mA·cm–2 in simulated industrial environment, it only demands a voltage of 2.38 V and offers remarkable stability for more than 30 h, providing great potential for large-scale applications. Such excellent performance should be attributed to the doping of P or S which optimizes the electronic structure of the Ni active sites, and the unique microdendritic structure exposes more catalytic active sites. This work may open up a new way for the design and preparation of earth-abundant, low-cost bifunctional electrocatalysts with high efficiency and stability in an industrial environment, which is of great significance for the practical application of electrolytic water hydrogen production technology in commercial fields.