Unique sandwich-cookie-like nanosheet array heterojunction bifunctional electrocatalyst towards efficient overall...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient electrocatalysts is crucial for overall water splitting (OWS) and seawater splitting (SWSS).
• Heterostructure construction offers a promising strategy to enhance catalytic activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER).

Purpose of the Study:

• To design and synthesize an efficient bifunctional electrocatalyst for overall water/seawater splitting.
• To investigate the catalytic performance and mechanism of the novel heterostructure for HER and OER.

Main Methods:

• Synthesis of a ruthenium/nickel phosphorus heterostructure on nickel hydroxide (Ni(OH)2) supported by nickel foam (NF).
• Electrochemical characterization including overpotential measurements for HER and OER at various current densities.
• Durability testing for overall water/seawater splitting.

Main Results:

• The Ru-P-Ni(OH)2/NF (RNPOH/NF) electrocatalyst exhibited low overpotentials for alkaline HER (98 mV at 10 mA cm-2) and OER (230 mV at 20 mA cm-2).
• RNPOH/NF achieved cell voltages of 1.7-1.94 V for overall water/seawater splitting at current densities of 50-100 mA cm-2.
• The catalyst demonstrated good durability over 12 hours of operation.

Conclusions:

• The constructed Ru-P-Ni(OH)2 heterostructure significantly enhances bifunctional catalytic activity for overall water/seawater splitting.
• The unique hydrolysis layer and interfacial electronic interactions are key to the improved performance.
• This work provides valuable insights for designing advanced electrocatalysts for clean energy applications.