Copper dendrite stabilized NiFe(OH) electrocatalyst for durable alkaline hydrogen evolution over 1000 h

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Developing efficient electrocatalysts for hydrogen evolution reaction (HER) in alkaline media is crucial for sustainable energy technologies.
• Maintaining catalyst stability under demanding operational conditions, such as high current densities and alkaline environments, remains a significant challenge.

Purpose of the Study:

• To design and synthesize a durable electrocatalyst for the hydrogen evolution reaction in alkaline media.
• To investigate the protective mechanism of *in situ* generated copper nanodendrites on the nickel-iron hydroxide catalyst.
• To evaluate the long-term stability and performance of the designed electrocatalyst for high-performance water splitting.

Main Methods:

• Electrocatalyst design and synthesis of Cu/NiFe(OH).
• Characterization of the catalyst structure and composition.
• Electrochemical testing for hydrogen evolution reaction in 1 M KOH.
• Long-term stability testing of the electrocatalyst coupled with a NiFe-layered double hydroxide anode for water splitting.

Main Results:

• The *in situ* generated copper nanodendrites effectively protected the NiFe(OH) from hydrogenation.
• The Cu/NiFe(OH) electrocatalyst exhibited a > 1000-hour lifetime under high-performance water splitting conditions.
• The system achieved high performance at 1.51 V and 10 mA cm^-2 in 1 M KOH when coupled with a NiFe-layered double hydroxide anode.

Conclusions:

• The designed Cu/NiFe(OH) electrocatalyst offers a durable and high-performance solution for hydrogen evolution reaction in alkaline media.
• The protective role of copper nanodendrites is key to achieving long-term catalyst stability.
• This advancement holds promise for efficient and sustainable water splitting applications.