A novel route to synthesize B₆O powder via reaction between CaB₆ and B₂O₃

A novel approach was applied to synthesize B 6 O using CaB 6 and B 2 O 3 powders as reactants. CaB 6 and B 2 O 3 were reacted to generate B 6 O and CaB 2 O 4 at 1573 K, and the by‐product CaB 2 O 4 was removed by acid leaching. It was found that the samples prepared in this work were oxygen deficient (B 6 O x , x ≈ .76–.77). The optimal molar ratio of CaB 6 to B 2 O 3 was determined to be 3:5, and excess B 2 O 3 could not lead to a change in the value of oxygen occupancy. Scanning electron microscope images showed that regular holes similar to the morphologies of CaB 6 particles were exhibited in the final samples, which could be explained by the diffusion of CaB 6 during the reaction process.