LiNbO₃—A Polar Material for Solid-Gas Artificial Photosynthesis

Abstract

The photocatalytic fixation of CO₂ to hydrocarbons was performed using LiNbO₃. 0.126 cm² of powdered LiNbO₃ was irradiated with 64.2 mW/cm² light from a mercury lamp with 10ml of water under 30% CO₂/air. The LiNbO₃ was held on a platen above the water to give a gas-solid catalytic reaction. Formic acid and formaldehyde were detected in the water after irradiation for 6 hours and produced at rates of 7.7 mmol and 1.1 μmol /hour. The calculated efficiency of the catalyst was calculated to be ca 2% which compared to 0.17% for TiO₂ under the same conditions. MgO doped LiNbO₃ was also tested and found to have an energy conversion efficiency of 0.72%.

Keywords:

• Ferroelectric
• photocatalysis
• carbon dioxide