“The practical applications of this work include the development of future technology that will transform CO2 (carbon dioxide) into useful materials, including what we call ‘solar fuel,’” Dr. Fernando Uribe-Romo, a research professor who worked on the project, told Digital Trends. “This is very important because at the rate we currently emit CO2, plants on earth are not able to fixate this CO2 back into the earth — resulting in accumulation in the atmosphere, which is why we have global warming.”
The work involved the preparation of materials called metal-organic frameworks (MOFs). These materials contain nanometer-sized holes small enough to absorb carbon dioxide. They are then able to capture sunlight and store its energy in chemical bonds, transforming carbon dioxide into an intermediate state between CO2 and sugar.
Previous work by scientists has demonstrated that MOF materials can be used in this way to absorb energy from natural light. However, those earlier materials were both pricey and rare, and scientists have had difficulty developing alternative materials able to absorb sufficient energy to trigger photosynthesis.
“We made MOFs that contain titanium, a metal that is used commonly in artificial photosynthesis,” Uribe-Romo continued. “We added molecules that we call ‘light harvesting antennae’ that can help capture sun rays to promote the chemical transformations at more efficient rates.”
These light-absorbing materials are called N-alkyl-2-aminoterephthalates, and allowed for the absorption of blue light.
The eventual target, Uribe-Romo said, is to make synthetic materials that are as efficient as plants, or even more so, when it comes to carrying out photosynthesis. That could still be a way off, however. Right now, what the team has demonstrated is that this is a feasible technology. Next up is plenty more R&D to optimize the technique for real world use-cases.
“I foresee these materials being utilized primarily in large scale technologies that produce large amounts of carbon dioxide, for example power plants or in gas flare at oil refineries or oil drill sites,” Uribe-Romo concluded.
The work is described in a new paper published in the Journal of Materials Chemistry A.
