Near-zero thermal expansion of In_2(1-x)(HfMg)_xMo₃O₁₂ with tailored phase transition

Solid solutions of In_2(1-x)(HfMg)_xMo₃O₁₂ are synthesized by solid state reaction with the aim to reduce the phase transition temperature of In₂Mo₃O₁₂ and improve its thermal expansion property. The effects of (HfMg)⁶⁺ incorporation on the phase transition and thermal expansion are investigated. It is shown that the monoclinic-to-orthorhombic phase transition temperature obviously decreases and the coefficient of thermal expansion (CTE) of the orthorhombic becomes less negative and approaches to zero with increasing the content of (HfMg)⁶⁺. A near zero thermal expansion covering the case at room temperature (RT) is achieved for the solid solutions with x≥0.85, implying potential applications of this material in many fields.