Water electrolysis for hydrogen production has garnered significant attention due to its high efficiency, environmental friendliness, and abundant resource availability. Developing cost-effective, efficient, and stable materials for water electrolysis is crucial. This study investigates NiFe-LDH, a highly efficient electrocatalyst for the oxygen evolution reaction (OER) in alkaline electrolytes and a bifunctional electrocatalyst for alkaline seawater electrolysis. Its unique layered structure and large specific surface area provide abundant active sites. The prepared NiFe-LDH-4 catalyst exhibits excellent OER performance in 1.0 M KOH electrolyte, requiring only 235 mV overpotential at a current density of 50 mA cm⁻² and demonstrating a Tafel slope of 80.32 mV dec⁻¹. In alkaline seawater electrolyte, it maintains outstanding OER performance while also showing excellent hydrogen evolution reaction (HER) capabilities. Compared to 1.0 M KOH electrolyte, the hydrogen evolution overpotential at −10 mA cm⁻² current density decreased by 88.5 mV, with the Tafel slope reduced by 53.6 mV dec⁻¹. Meanwhile, OER maintained excellent stability in a 1.0 M KOH electrolyte at a current density of 500 mA cm⁻², and an AEMWE device was constructed. The NiFe-LDH electrocatalyst demonstrates exceptional catalytic activity and high stability, making it a promising candidate for industrial-scale production.

The material demonstrates a specific capacitance of 844.8 C g ⁻¹ at a current density of 1 A g ⁻¹ . In addition, the hydrogen evolution reaction performance of the material is 92.7 mV at 10 mA cm ⁻² , with a Tafel slope of 147.86 mV dec ⁻¹ .

In situ hydrothermal growth of NiFe-LDH on hydrothermally synthesized and phosphorized NiCoP nanoneedles for hierarchical NiCoP@NiFe-LDH heterostructure electrocatalysts.

CuCo ₂ S ₄ nanowires were synthesized via hydrothermal and air annealing. They showed excellent HER performance with low overpotentials of 86.2 mV in KOH and 91.2 mV in seawater. For the OER, the overpotential decreased from 282.8 mV in KOH to 255.6 mV in seawater.

In this study, a two-step hydrothermal method is used to prepare NiCo₂O₄@NiMoO₄ nanoscale materials for periodic stability supercapacitors.