Amorphous conversion in pyrolytic symmetric trinuclear nickel clusters trigger trifunctional electrocatalysts

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Designing amorphous multifunctional electrocatalysts is challenging due to structural disorder and thermal instability.
• Amorphous materials offer unique properties for catalytic applications.

Purpose of the Study:

• To develop a strategy for the rational design of amorphous multifunctional electrocatalysts.
• To preserve the local short-range structures of molecular precursors during pyrolysis.

Main Methods:

• Tandem (low-temperature/250-350 °C) pyrolysis of Schiff base nickel molecular clusters (Ni3[2(C21H24N3Ni1.5O6)]).
• Characterization of temperature-dependent residuals to evaluate electrocatalytic performance.

Main Results:

• The synthesized amorphous nickel material exhibited exceptional activity and stability for oxygen evolution reaction (OER), urea oxidation reaction (UOR), and methanol oxidation reaction (MOR).
• Specific nickel atom motifs (Ni1, Ni1', Ni2) were identified as crucial for different electrocatalytic processes (Ni1/Ni1' for UOR/MOR, Ni2 for OER).
• Electrocatalytic performance metrics: OER (η10 = 197 mV), UOR (η10 = 1.339 V), MOR (1358 mA cm⁻² at 0.56 V).

Conclusions:

• Tandem pyrolysis of molecular clusters is an effective strategy for creating stable amorphous multifunctional electrocatalysts.
• Disordered engineering in molecular clusters via tandem pyrolysis enables the development of advanced electrocatalysts.
• The identified nickel atom motifs provide insights for designing highly efficient and selective electrocatalysts.