(FeMnCe)-co-doped MOF-74 with significantly improved performance for overall water splitting

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing inexpensive and highly active electrocatalysts is crucial for efficient overall water splitting.
• Non-precious metal catalysts are sought after to replace expensive noble metals.

Purpose of the Study:

• To design and synthesize novel 3d-4f trimetallic MOF-74 materials for overall water splitting.
• To investigate the electrocatalytic performance of these materials for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).

Main Methods:

• Synthesis of a series of 3d-4f (FeMnCe)-trimetallic MOF-74 materials with varying metal ratios.
• Electrocatalytic performance evaluation in alkaline solution (1 M KOH) for OER and HER.
• Testing in an overall water splitting system and a cell unit with Pt/C.

Main Results:

• FeMn6Ce0.5-MOF-74/NF demonstrated superior electrocatalytic performance.
• Low overpotentials were achieved: 281 mV for OER and 186 mV for HER at specific current densities.
• Overall water splitting required only 1.65 V, and a cell unit with Pt/C needed 1.40 V at 10 mA cm-2.

Conclusions:

• The design of 3d-4f mixed-metallic MOF-74 offers a new strategy for developing efficient non-precious metal electrocatalysts.
• FeMn6Ce0.5-MOF-74/NF shows significant potential for applications in water splitting technologies.
• This work provides a new viewpoint for designing advanced electrocatalysts.