Low Au-content CoAu electrodes for environmental applications.

Area of Science:

• Electrochemistry
• Materials Science
• Environmental Science

Background:

• Developing novel electrode materials is crucial for advanced electrochemical sensing and energy applications.
• Cobalt-gold (CoAu) alloys offer unique catalytic and conductive properties.
• Electroless deposition provides a versatile method for fabricating CoAu nanostructures.

Purpose of the Study:

• To synthesize and characterize CoAu electrodes using electroless deposition.
• To evaluate the efficacy of CoAu electrodes for electrochemical sensing of arsenic(III).
• To assess the performance of CoAu electrodes as anodes in direct borohydride-hydrogen peroxide fuel cells.

Main Methods:

• Electroless deposition of cobalt-gold (CoAu) electrodes with varying parameters.
• Characterization using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), N2 sorption, and X-ray powder diffraction (XRD).
• Electrochemical sensing of arsenic(III) and performance evaluation in direct borohydride-hydrogen peroxide fuel cells (DBHPFC).

Main Results:

• Optimized CoAu electrode achieved a low limit of detection of 2.16 ppb for arsenic(III).
• The CoAu electrode demonstrated activity for arsenic oxidation, even with copper(II) as an interferent and in real samples.
• A peak power density of 191 mW cm⁻² was achieved for DBHPFC using the CoAu anode at 25 °C, increasing with temperature.

Conclusions:

• CoAu electrodes prepared by electroless deposition are effective for sensitive electrochemical detection of arsenic(III).
• CoAu electrodes exhibit significant potential as anodes in direct borohydride-hydrogen peroxide fuel cells.
• The study highlights the dual applicability of CoAu electrodes in environmental monitoring and energy conversion.