Oxide impurities such as boria (B
2O
3) and zirconia (ZrO
2) on the surfaces of zirconium diboride (ZrB
2) particles are known to limit their sinterability. Among the impurities, B
2O
3 on the surface of ZrB
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Oxide impurities such as boria (B
2O
3) and zirconia (ZrO
2) on the surfaces of zirconium diboride (ZrB
2) particles are known to limit their sinterability. Among the impurities, B
2O
3 on the surface of ZrB
2 particles could be easily removed by methanol or hydrofluoric acid. However, the remaining ZrO
2 still gave negative influences on the sinterability. In this study, ZrB
2 particles were treated with various acids to remove oxide impurities on their surfaces. The acid treatments were found to vary in efficacy, according to acid type, and affect the crystallinity and morphology of ZrB
2 particles to varying degrees, in some cases forming additional impurities. In particular, the change in the oxygen content of the ZrB
2 particles induced by acid treatment was found to depend on the type of acid. The results of the acid treatments were compared which revealed that HNO
3 treatment optimizes the purity of ZrB
2 particles. In addition, the effects of acid treatment on the surface properties of ZrB
2 particles were considered. In particular, the correlation between the surface properties of the acid-treated ZrB
2 particles and their dispersibility in aqueous solution was investigated.
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