High-entropy oxides (HEOs) stabilize multiple cations in a single solid solution phase, providing a new opportunity for property engineering in almost infinite compositional space. The structural stability and tunability of HEO are of great interest and importance but has not been well understood, especially under pressure. Here, we studied the structure evolution of a rock salt phase (Co_0.2Cu_0.2Mg_0.2Ni_0.2Zn_0.2)O HEO using in situ synchrotron X-ray diffraction, pair distribution function, Raman spectroscopy up to ~43 GPa, and ex situ transmission electron microscopy, a pressure-induced reversible rock salt to highly distorted cubic phase transition was observed. These results suggest highly tunable lattice distortion in HEOs under pressure, which could promote the fundamental understanding and also guide applications of HEOs.

高熵氧化物（HEO）可在单个固溶体相中稳定多个阳离子，为几乎无限的组成空间中的性能工程提供了新的机会。HEO的结构稳定性和可调谐性引起人们极大的兴趣和重要性，但尚未得到很好的理解，尤其是在压力下。在这里，我们使用原位同步加速器X射线衍射，成对分布函数，高达〜43 GPa的拉曼光谱和非原位研究了岩盐相（Co _0.2 Cu _0.2 Mg _0.2 Ni _0.2 Zn _0.2）O HEO的结构演化透射电子显微镜下，观察到压力诱导的可逆岩盐向高度扭曲的立方相转变。这些结果表明在压力下HEO的晶格畸变高度可调，这可以促进基本理解并指导HEO的应用。