CO₂ Electroreduction To Syngas With Tunable Composition In An Artificial Leaf

Area of Science:

• Artificial photosynthesis
• Catalysis
• Renewable energy

Background:

• Artificial leaves (a-leaves) offer a pathway to convert carbon dioxide into syngas using solar energy.
• Integration with thermo- and biocatalytic processes can decentralize valuable product manufacturing.
• Current a-leaf designs optimize for fixed syngas composition, limiting flexibility.

Purpose of the Study:

• To demonstrate that electrolyte flow can be a design variable for flexible syngas production in a-leaves.
• To achieve controllable CO:H2 ratios without compromising a-leaf performance.
• To assess the feasibility using a specific catalyst and photovoltaic module.

Main Methods:

• Utilized a commercial cell with a Cu2O:Inx cathodic catalyst and an amorphous silicon thin-film photovoltaic module.
• Investigated the effect of catholyte flow rate on syngas composition (CO:H2 ratio).
• Measured cell voltage deviation to assess performance impact.

Main Results:

• Achieved controllable CO:H2 ratios ranging from 1.8 to 2.3.
• Maintained performance with only a 2% deviation from optimal cell voltage.
• Demonstrated that catholyte flow solely controls the syngas ratio.

Conclusions:

• Electrolyte flow is a viable design parameter for flexible syngas production in a-leaves.
• This control enables tailored syngas compositions for diverse downstream processes.
• The developed a-leaf system shows promise for decentralized chemical production.