A domestic research team has developed a new material that can effectively block "space radiation," a major obstacle to space exploration. With higher shielding efficiency than existing materials, it is expected to help astronauts stay longer during lunar missions.
A team led by Senior Researcher Jang Se-gyu at the Korea Institute of Science and Technology (KIST) Functional Composite Materials Research Center said on the 6th that, together with a team led by Professor Choi Si-young at the Korea Advanced Institute of Science and Technology (KAIST), they developed a protective barrier that tightly arranges boron nitride nanotubes (BNNT) to be strong, conduct heat well, and efficiently block space radiation.
Space radiation consists of high-energy particles that can damage human cells and DNA, potentially causing cancer. In particular, "secondary neutrons" generated when space radiation collides with metals and other materials are known to be up to 20 times more dangerous than ordinary radiation.
Aluminum, widely used as a spacecraft material, has the limitation that below a certain thickness it can actually generate these secondary neutrons, creating the need for a new substitute material. BNNT drew attention as an alternative, but it remained in the form of thin, brittle sheets, making real-world use difficult.
The researchers developed a technique that allows BNNT to disperse evenly in water without clumping. Based on this, they produced BNNT in a liquid crystal form and successfully aligned it in one direction, fabricating a BNNT film that is far denser and more uniform than before.
The finished film has more than three times the density of existing films, and its neutron shielding performance increased 3.7 times. At the same time, it is flexible and strong, and is expected to be usable in manufacturing various structures.
Its performance was also verified in simulations conducted jointly with NASA. Under the same thickness and mass conditions, the BNNT film showed 15% higher radiation shielding efficiency than aluminum and demonstrated excellent performance in blocking secondary neutrons.
The team projected that using this material could provide lunar mission astronauts with a radiation safety environment comparable to the International Space Station (ISS), potentially doubling mission duration.
Jang said, "We have overcome manufacturing process barriers so that BNNT, a nanomaterial, can be used as an actual space radiation shielding material," adding, "With high mechanical strength and thermal conductivity, it has great potential not only in space but also in aviation, defense, and nuclear power generation and other advanced fields."
The results were published on Aug. in the international journal "Advanced Functional Materials."
References
Advanced Functional Materials(2025), DOI: https://doi.org/10.1103/4vdx-7224