CO₂ -Reductive, Copper Oxide-Based Photobiocathode for Z-Scheme Semi-Artificial Leaf Structure.

Area of Science:

• Bioinorganic Chemistry
• Artificial Photosynthesis
• Electrocatalysis

Background:

• Natural photosynthesis utilizes Z-scheme water oxidation and Calvin cycle CO2 fixation.
• Developing artificial systems to mimic these processes is crucial for sustainable energy solutions.

Purpose of the Study:

• To create a wireless, solar-driven, semi-biological photoelectrochemical (PEC) device for CO2 reduction.
• To enhance the efficiency and stability of CO2 conversion using biohybrid materials.

Main Methods:

• Assembling a biohybrid photocathode using formate dehydrogenase (ClFDH) interfaced with a TiO2-coated CuFeO2 and CuO electrode (ClFDH-TiO2|CFO).
• Integrating the photocathode with a water-oxidizing FeOOH-coated BiVO4 photoanode to form a wireless Z-scheme PEC device.
• Investigating the device's performance for bias-free CO2-to-formate conversion under visible light.

Main Results:

• The TiO2 layer improved the photoelectrochemical stability of the CFO electrode and electron transfer to ClFDH.
• The assembled semi-artificial leaf demonstrated efficient, bias-free CO2 reduction to formate.
• Formate production rate was 2.45 times higher with ClFDH compared to the system without the enzyme.

Conclusions:

• This work represents the first wireless solar-driven semi-biological PEC system for CO2 reduction using water as an electron feedstock.
• The biohybrid approach significantly enhances the efficiency of CO2 conversion.
• The developed system shows promise for sustainable carbon capture and utilization technologies.