在富氢化合物中,一方面由于非氢元素的存在会对氢的子晶格产生化学预压作用,这些体系比纯氢更容易金属化.另一方面由于含氢量较多,富氢化合物可能会具有像金属氢那样较高的超导转变温度,有望成为超导家族的新成员—–氢基超导体.高压下富氢化合物的结构及超导电性已成为物理、材料等多学科的研究热点,最近理论和实验发现硫氢化合物在高压下的超导转变温度达到200 K,创造了高温超导新纪录,进一步推动了人们对富氢化合物超导电性的研究.本文主要介绍了近年来高压下几种典型富氢化合物的结构、稳定性、原子间相互作用、金属化及超导电性,希望未来能在富氢化合物中寻找到具有更高超导转变温度的超导体.%Metallic hydrogen can be realized theoretically at high pressure, which suggests that it will be a room-temperature superconductor due to the high vibrational frequencies of hydrogen atoms. However, the metallic state of hydrogen is not observed in experiment at up to 388 GPa. Scientists have been exploring various new ways to achieve hydrogen metalliza-tion. Hydrogen-rich compounds can be metallized at much lower pressures because of chemical pre-compression. More-over, because such materials are dominated by hydrogen atoms, some novel properties can be found after metallization, such as high Tc superconductivity. Therefore, hydrogen-rich compounds are potential high-temperature superconductors, and this method is also believed to be an effective way to metalize hydrogen, which has aroused significant interest in lots of fields, such as physics, material science, etc. In a word, hydrogen-rich compounds are expected to become a new member of superconductor family: hydrogen-based superconductor. Very recently, the theoretical prediction and the successful experimental discovery of high-temperature superconductivity at 200 K in a sulfur hydride compound at high pressure have set a record, which inspired further efforts to study the superconductivity of hydrogen-rich compounds. The present review focuses on crystal structures, stabilities, interaction between atoms, metallization, and superconduc-tivity of several typical hydrogen-rich compounds at high pressures. Furthermore, higher Tc superconductors can be expected to be found in hydrogen-rich compounds in the future.
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