# Carbon Dioxide Pressure and Catalyst Quantity Dependencies in Artificial Photosynthesis of Hydrocarbon Chains on Nanostructured Co/CoO Surfaces

## TL;DR

This study explores how pressure and catalyst quantity affect the artificial photosynthesis of hydrocarbons using Co/CoO surfaces.

## Contribution

The study reveals optimal pressure and catalyst quantity for maximizing hydrocarbon yield in artificial photosynthesis.

## Key findings

- Optimal CO2 adsorption and hydrocarbon yield occur at 0.40 MPa pressure.
- Low pressure reduces CO2 adsorption, while high pressure causes surface blockage.
- Hydrocarbon yield increases with the amount of Co/CoO catalyst used.

## Abstract

In this study, we investigated the influence of pressure and the quantity of Co/CoO catalyst on an artificial photosynthesis process that converts CO2 and H2O into hydrocarbons (CnH2n+2, where n ≤ 18). The adsorption of CO2 and H2O on Co/CoO surfaces proved to be pivotal in this photo-catalytic reaction. Photoexcited carbon dioxide and water molecules ((CO2)* and (H2O)*) generated by illuminating the catalyst surface led to the formation of alkene hydrocarbon molecules with carbon numbers following an approximate Poisson distribution. The optimal pressure was found to be 0.40 MPa. Pressure less than 0.40 MPa resulted in low CO2 adsorption, impeding excitation for photosynthesis. At greater pressure, oil/wax accumulation on Co/CoO surfaces hindered CO2 adsorption, limiting further photosynthesis reactions. The average number of carbon atoms in the hydrocarbons and hydrocarbon yield were correlated. The amount of Co/CoO was also found to affect the hydrocarbon yield. Our study contributes to the understanding of Co/CoO-catalyzed photosynthesis and suggests that an open-flow system could potentially enhance the productivity of long-chain hydrocarbons.