A groundbreaking 3D printing technique is poised to revolutionize the efficiency of solar fuel production, potentially paving the way for more economically viable sustainable aviation fuels. Engineers at ETH Zurich have been at the forefront of renewable energy innovation. In 2019, they unveiled a complete thermochemical process for generating liquid fuels from sunlight and air, and now, their latest advancement promises to further transform this technology.
Central to this groundbreaking process is a solar reactor capable of harnessing concentrated sunlight, reaching scorching temperatures of up to 1,500°C. Inside the reactor, a cleverly devised thermochemical cycle effectively splits water and CO2 previously extracted from the atmosphere, resulting in the creation of syngas—a combination of hydrogen and carbon monoxide. These syngas can be converted into liquid hydrocarbon fuels like kerosene, offering the potential to fuel the aviation industry while maintaining a carbon-neutral footprint.
However, prior attempts faced limitations due to structures with isotropic porosity. These structures hindered the efficient transport of solar radiation into the reactor, thereby restricting internal temperature and fuel production.
The breakthrough comes in the form of a 3D printing methodology developed by researchers from ETH Zurich’s André Studart and Aldo Steinfeld groups. This innovative approach enables the creation of ceramic structures with intricate pore geometries, ensuring the efficient transmission of solar radiation into the core of the reactor.
As described in a publication in Advanced Materials Interfaces, their hierarchical designs incorporate channels and pores that expand at the surface exposed to sunlight and gradually narrow toward the rear of the reactor. This configuration maximizes the absorption of concentrated solar radiation throughout the entire structure, guaranteeing that the entire porous framework reaches the crucial 1,500°C temperature, thus significantly enhancing fuel production.
The manufacturing process relies on extrusion-based 3D printing and a specially formulated ink with low viscosity and a high concentration of ceria particles. This unique ink maximizes the presence of redox-active material.
Initial testing has yielded promising results. These hierarchical structures, when exposed to the same intense solar radiation (equivalent to 1,000 suns), produce twice as much fuel as their uniform counterparts. The implications of this breakthrough are substantial, as it brings us one step closer to harnessing solar energy for sustainable fuel production, potentially reshaping the future of aviation and reducing our carbon footprint.