Fabrication and characteristics of Li4SiO4 pebbles by a novel capillary-based microfluidic wet process

The synthesis of Li4SiO4 pebbles used as tritium breeder by a microfluidic technology was studied for the first time. C2H3O2Li·2H2O powder and SiO2–sol were used as the raw materials with the Li and Si molar ratio of 4. Highly uniform size droplets were formed easily in a capillary-based microfluidic device. The droplets were then converted into gel pebbles. After reaction at 750 °C for 4 h, the designated Li4SiO4 pebbles were obtained. The size of as-prepared Li4SiO4 pebbles can be controlled precisely in the size range from tens of micrometer to a millimeter. The obtained Li4SiO4 micrometer-pebbles possess a narrow size distribution (CV = 3.9%) and favorable shape with good sphericity (1.05). The density is 82% T.D. Phase analysis, thermal analysis, morphological observation and sintering behavior of the pebbles were carried out systematically. The XRD patterns revealed that Li4SiO4 were successfully obtained and the pebble’s microstructure was studied by electron beam lithography machine.