Optimized negative thermal expansion property in low-cost Mg2P2O7-based bulk material

Negative thermal expansion (NTE) is an intriguing physical phenomenon, which is of great significance for the high precision application. In this work, we have realized to broaden the NTE temperature zone in Mg2P2O7-based bulk material by doping Cu atom on the Mg site. A joint study of Raman scattering and X-ray diffraction (XRD) indicates that there are double phases in the NTE temperature zone, and the NTE of Mg1.9Cu0.1P2O7 bulk material comes from the phase transition of α- and β-phase. The present work provides a way to optimize negative thermal expansion property in phase transition typed materials.