Hierarchical Ohmic Contact Interface Engineering for Efficient Hydrazine-Assisted Hydrogen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Hydrazine oxidation reaction coupled with hydrogen evolution reaction (HER) is crucial for low-energy water splitting and hydrogen production.
• Developing electrocatalysts with dual active sites is key for hydrazine-assisted HER systems.
• Current electrocatalyst performance at high current densities remains a significant challenge.

Purpose of the Study:

• To design and investigate a hierarchical Ohmic contact interface engineering strategy.
• To bridge NiMo and Ni2P heterojunctions for improved performance in hydrazine-assisted HER.
• To reduce charge transfer impedance and energy barriers for industrial current density applications.

Main Methods:

• Fabrication of a hierarchical Ohmic contact interface between NiMo and Ni2P.
• Investigation of charge redistribution and energy barriers at the Ohmic contact interface.
• Electrocatalytic performance testing of the NiMo/Ni2P heterojunction in an overall hydrazine splitting (OHzS) electrolyzer.

Main Results:

• The hierarchical Ohmic contact interface effectively eliminated charge transfer impedance.
• The NiMo/Ni2P heterojunction achieved low cell voltages of 181 mV at 100 mA cm-2 and 343 mV at 500 mA cm-2.
• The system demonstrated high electrocatalytic stability for hydrogen production.

Conclusions:

• Hierarchical Ohmic contact interface engineering is a viable strategy for enhancing electrocatalyst performance.
• This approach significantly reduces the energy required for hydrazine-assisted water splitting at high current densities.
• The developed NiMo/Ni2P heterojunction offers a promising pathway for low-energy hydrogen production.