A step towards efficient water splitting: a high-performance CuCo(OH)₂/CNT/MoS₂ electrocatalyst

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient electrocatalysts is crucial for sustainable energy technologies like water splitting.
• Existing catalysts often suffer from low activity, poor stability, or high cost.
• Bifunctional electrocatalysts that can catalyze both oxygen evolution and hydrogen evolution reactions are highly desirable.

Purpose of the Study:

• To synthesize and characterize a novel CuCo(OH)₂/CNT/MoS₂ composite electrocatalyst.
• To evaluate the electrocatalytic performance of the composite for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).
• To investigate the durability and efficiency of the composite for overall water splitting (OWS).

Main Methods:

• Rapid co-precipitation synthesis of the CuCo(OH)₂/CNT/MoS₂ composite.
• Electrochemical characterization including overpotential, Tafel slope, and cyclic voltammetry.
• Durability testing in alkaline and acidic media.
• Calculation of turnover frequency (TOF) and mass activity.

Main Results:

• The CuCo(OH)₂/CNT/MoS₂ composite exhibited low overpotentials for OER (65 mV) and HER (211 mV) at η₁₀.
• Exceptional durability was observed, with activity maintained for over 40 hours (alkaline) and 25 hours (acidic).
• Overall water splitting required only 170 mV overpotential, significantly decreasing after stability tests.

Conclusions:

• The synergistic effect between CuCo(OH)₂, CNT, and MoS₂ enhances electrical conductivity and surface area, boosting electrochemical performance.
• The synthesized composite is a highly efficient and durable bifunctional electrocatalyst for overall water splitting.
• This material holds significant promise for advancing hydrogen production technologies.