Superconductivity at 40 K in lithiation-processed [(Fe,Al)(OH)2][FeSe]1.2 with a layered structure

Autor: Hu, Guobing, Shi, Mengzhu, Wang, Wenxiang, Zhu, Changsheng, Sun, Zeliang, Cui, Jianhua, Zhuo, Weizhuang, Yu, Fanghang, Luo, Xigang, Chen, Xianhui
Rok vydání: 2021
Předmět:
Zdroj: Inorganic Chemistry (2021)
Druh dokumentu: Working Paper
DOI: 10.1021/acs.inorgchem.0c03686
Popis: Exploration of new superconductors has always been one of the research directions in condensed matter physics. We report here a new layered heterostructure of [(Fe,Al)(OH)2][FeSe]1.2, which is synthesized by the hydrothermal ion-exchange technique. The structure is suggested by a combination of X-ray powder diffraction and the electron diffraction (ED). [(Fe,Al)(OH)2][FeSe]1.2 is composed of the alternating stacking of tetragonal FeSe layer and hexagonal (Fe,Al)(OH)2 layer. In [(Fe,Al)(OH)2][FeSe]1.2, there exists mismatch between the FeSe sub-layer and (Fe,Al)(OH)2 sub-layer, and the lattice of the layered heterostructure is quasi-commensurate. The as-synthesized [(Fe,Al)(OH)2][FeSe]1.2 is non-superconducting due to the Fe vacancies in the FeSe layer. The superconductivity with a Tc of 40 K can be achieved after a lithiation process, which is due to the elimination of the Fe vacancies in the FeSe layer. The Tc is nearly the same as that of (Li,Fe)OHFeSe although the structure of [(Fe,Al)(OH)2][FeSe]1.2 is quite different from that of (Li,Fe)OHFeSe. The new layered heterostructure of [(Fe,Al)(OH)2][FeSe]1.2 contains an iron selenium tetragonal lattice interleaved with a hexagonal metal hydroxide lattice. These results indicate that the superconductivity is very robust for FeSe-based superconductors. It opens a path for exploring super-conductivity in iron-base superconductors.
Comment: 7 pages, 4 figures, published in Inorg. Chem
Databáze: arXiv