Collaborative studies on Bio-D and Cold TAS; Hydrogels that capture radioactive cesium in water

Fukazawa, Hiroshi

Water and ice are the most common liquid and solid on Earth, and they constitute an important medium. Hydrogels are unique materials because large amounts of water can be contained among their 3D cross-linked polymer chains. Water content varies from a dry condition to nearly 98 wt %. The scanning electron microscope image shows that hydrogels have empty spaces that can accommodate water molecules. However, the structure and dynamics of water molecules in these spaces are not fully understood at the atomic level. Neutron is useful to investigate water and hydrogen bonding because of the large neutron scattering cross sections. Therefore, we have used neutron beam to study gels at the HANARO, KAERI. We here show neutron diffraction and scattering of hydrogels with acrylamide or polysaccharides, which contain weak hydrogen bond or low-density water. Furthermore, we report a new hydrogel developed by QuBS, JAEA. This hydrogel has been tested as a cesium capturing material and is important in the Fukushima recovery effort.