Researchers have recently found a way to trigger photosynthesis – the process used by plants to convert the sunlight energy into chemical energy, through carbon dioxide (CO2) consumption – by exciting a specific material with a blue LED.
Such a discovery could thus be an answer to air pollution and greenhouse effects linked to CO2. It could also lead to a new form of energy production, based on CO2 and sunlight.
Extensive research has been directed towards CO2 reduction for several decades. More specifically, the solar powered photocatalysis of CO2 reduction to other compounds, commonly known as solar fuels, has been gaining momentum. However the main issues regarding this reaction are:
- the stability of CO2, which is a fully oxidized and thermodynamically stable molecule ,
- finding a visible light-compatible photocatalyst;
- the cost-effectiveness of the process: platinum, rhenium and iridium can absorb visible light but are rare and expensive;
- the energy-effectiveness of the process.
University of Central Florida’s Professor Fernando Uribe-Romo and his team have developed such a process for CO2 reduction. N-alkyl-2-aminoterephtalates, that are designed to absorb specific colours of light, have been incorporated into a titanium based metal-organic framework MIL-125. Uribe-Romo and his team tailored this molecule to absorb specifically in the blue wavelengths.
Figure 1: Scheme of the photocatalytic reduction of CO23
The MIL-125-NHR framework exhibits interesting visible light absorption properties as well as CO2 reduction capacity. The blue LED-activated system is thus able to recreate a photosynthesis reaction, by turning CO2 into its reduced counterparts (formates, formamides) that can be reinjected in an energy production process. Such technology could thus represent a real breakthrough in the greenhouse gases management, clean energy production and circular economy areas.
Indeed, if properly designed, this material could be implemented in power plants to treat CO2 emissions and fuel the energy production processes. It could also be used in the housing industry in order to clean ambient air as well as producing energy directly from sunlight.
Nicolas, Consultant, Leyton France
 Hori, Y. (2008). Electrochemical CO2 reduction on metal electrodes. In Modern aspects of electrochemistry (pp. 89-189). Springer New York.
 Rakowski Dubois, M., & Dubois, D. L. (2009). Development of molecular electrocatalysts for CO2 reduction and H2 production/oxidation. Accounts of Chemical Research, 42(12), 1974-1982.
 Logan, M. W., Ayad, S., Adamson, J. D., Dilbeck, T., Hanson, K., & Uribe-Romo, F. J. (2017). Systematic variation of the optical bandgap in titanium based isoreticular metal–organic frameworks for photocatalytic reduction of CO 2 under blue light. Journal of Materials Chemistry A.
 See Cherif Larabi. Surface organometallic chemistry on Metal Organic Frameworks (MOF) : synthesis, characterization and their application in catalysis. Other. Universit´e Claude Bernard – Lyon I, 2011. English. for more information on MOF.