Expanded Negative Electrostatic Network-Assisted Seawater Oxidation and High-Salinity Seawater Reutilization.

Area of Science:

• Electrochemistry
• Materials Science
• Renewable Energy

Background:

• Seawater splitting for hydrogen electrosynthesis is promising for renewable energy.
• Anode design is challenging due to chlorine chemistry and salinity issues at high current densities.
• Sustainable utilization of high-salinity wastewater remains a neglected problem.

Purpose of the Study:

• To develop stable and efficient anodes for seawater electrolysis.
• To block surface chlorine chemistry and mitigate salinity effects.
• To enable sustainable reutilization of high-salinity wastewater.

Main Methods:

• Construction of phytate-based expanded negative electrostatic networks (ENENs) on hydroxides.
• Testing CoFe hydroxides with ENENs for alkaline seawater oxidation.
• Utilizing theoretical computations and in situ/ex situ characterizations to study mechanisms.

Main Results:

• ENENs enabled CoFe hydroxides to operate at >1 A cm⁻² with prolonged lifespans (1000 h at 1 A cm⁻², 900 h at 2 A cm⁻²).
• Trace phytates extended the lifespan of conventional CoFe hydroxides by ~28 times at 2 A cm⁻².
• ENENs demonstrated universal applicability across various materials and low-temperature operation.

Conclusions:

• Phytate-based ENENs offer a viable strategy for stable and efficient seawater electrolysis.
• This approach provides a sustainable method for utilizing high-salinity wastewater.
• The developed technology is eco-friendly and rivals existing energy storage devices.