MXene Boosted CoNi-ZIF-67 as Highly Efficient Electrocatalysts for Oxygen Evolution

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Oxygen evolution reaction (OER) is critical for sustainable energy, but requires efficient, low-cost electrocatalysts.
• Metal-organic frameworks (MOFs) show promise due to high surface area and tunable properties.
• Combining MOFs with conductive nanostructures can enhance catalytic performance.

Purpose of the Study:

• To synthesize and characterize a novel MXene-supported bimetallic MOF hybrid for OER.
• To investigate the synergistic effects of MXene and CoNi-ZIF-67 on OER activity.
• To evaluate the electrocatalytic performance of the hybrid compared to existing catalysts.

Main Methods:

• In-situ growth of bimetallic CoNi-ZIF-67 on a Ti3C2Tx (MXene) matrix via coprecipitation.
• Characterization of the hybrid material using various analytical techniques.
• Electrochemical evaluation of OER performance, including onset potential and Tafel slope.

Main Results:

• The synthesized CoNi-ZIF-67@Ti3C2Tx hybrid featured smaller MOF particles and increased average oxidation states of Co/Ni.
• The hybrid exhibited superior OER catalytic activity with a low onset potential of 275 mV vs. RHE.
• The Tafel slope was measured at 65.1 mV·dec−1, outperforming IrO2 and pure CoNi-ZIF-67.

Conclusions:

• The MXene support enhances the OER performance of CoNi-ZIF-67 by improving particle size and metal oxidation states.
• The synergistic effect between the MOF and MXene leads to excellent electrocatalytic activity.
• This work presents a new strategy for developing efficient, non-precious metal OER electrocatalysts.