A multicomponent γ-type (Gd1/6Tb1/6Dy1/6Tm1/6Yb1/6Lu1/6)2Si2O7 disilicate with outstanding thermal stability

A multicomponent rare-earth disilicate (Gd1/6Tb1/6Dy1/6Tm1/6Yb1/6Lu1/6)2Si2O7 has been designed and successfully synthesized following the strategy of high entropy engineering. The as-prepared single-phase 6RE-disilicate possesses a new γ-type crystal structure (monoclinic, P21/c) beyond the α-, β- and δ-type parent structures of six single RE disilicates. Six-species RE cations are homogeneously distributed on RE lattice sites and our multicomponent disilicate demonstrates outstanding thermal stability from room temperature up to around 1900°C. This work extends the knowledge of strategic multicomponent modification of complex ceramics with extremely high phase stability.