Development of Binder-Free Three-Dimensional Honeycomb-like Porous Ternary Layered Double Hydroxide-Embedded MXene...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Developing efficient electrocatalysts is crucial for sustainable energy technologies.
• Layered double hydroxides (LDHs) and MXenes show promise but often require synergistic integration.
• Bifunctional electrocatalysts for both hydrogen and oxygen evolution reactions are highly sought after.

Purpose of the Study:

• To fabricate a novel honeycomb-like porous-structured nickel-iron-cobalt layered double hydroxide/Ti3C2Tx (NiFeCo-LDH@MXene) composite.
• To evaluate the bifunctional electrocatalytic activity of the composite for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in an alkaline medium.
• To assess the performance of the composite in overall water splitting applications.

Main Methods:

• Hydrothermal synthesis of NiFeCo-LDH@MXene composite on 3D nickel foam.
• Electrochemical characterization including overpotential measurements for HER and OER.
• Assembly and testing of a NiFeCo-LDH@MXene//NiFeCo-LDH@MXene device for overall water splitting.

Main Results:

• The NiFeCo-LDH@MXene composite exhibited a unique honeycomb-like porous structure.
• The catalyst demonstrated outstanding bifunctional electrocatalytic activity for both HER and OER.
• Low overpotentials of 130 mV (OER) and 34 mV (HER) were required to achieve a current density of 10 mA cm⁻².
• An overall water splitting device achieved a cell voltage of 1.41 V at 10 mA cm⁻² with robust stability for over 24 hours.

Conclusions:

• The fabricated 3D porous NiFeCo-LDH@MXene composite shows excellent bifunctional electrocatalytic activity and stability.
• The material is a promising candidate for efficient and cost-effective electrocatalysts in green energy conversion devices.
• This work highlights the potential of integrating LDHs and MXenes for advanced energy applications.