Synthesis and structure of a non-van-der-Waals two-dimensional coordination polymer with superconductivity
Zhichao Pan, Xing Huang, Yunlong Fan, Shaoze Wang, Yiyu Liu, Xuzhong Cong, Tingsong Zhang, Shi‐Chao Qi, Ying Xing, Yu‐Qing Zheng, Jian Li, Xiaoming Zhang, Wei Xu, Lei Sun, Jian Wang, Jin‐Hu Dou
Abstract
Two-dimensional conjugated coordination polymers exhibit remarkable charge transport properties, with copper-based benzenehexathiol (Cu-BHT) being a rare superconductor. However, the atomic structure of Cu-BHT has remained unresolved, hindering a deeper understanding of the superconductivity in such materials. Here, we show the synthesis of single crystals of Cu3BHT with high crystallinity, revealing a quasi-two-dimensional kagome structure with non-van der Waals interlayer Cu-S covalent bonds. These crystals exhibit intrinsic metallic behavior, with conductivity reaching 103 S/cm at 300 K and 104 S/cm at 2 K. Notably, superconductivity in Cu3BHT crystals is observed at 0.25 K, attributed to enhanced electron-electron interactions and electron-phonon coupling in the non-van der Waals structure. The discovery of this clear correlation between atomic-level crystal structure and electrical properties provides a crucial foundation for advancing superconductor coordination polymers, with potential to revolutionize future quantum devices. Two-dimensional conjugated coordination polymers can show large electrical conductivity. Here, the authors synthesize high-quality single crystals of Cu3BHT to unveil the atomic structure and intrinsic superconducting properties.