Synthesis methods, basic physical properties, and potential applications of the FeSe superconductor

Among all Fe-based superconductors, FeSe has the simplest composition and crystal structure, with only the most basic structural unit, the FeSe layer. Due to the ease of synthesizing high-quality large FeSe superconducting single crystals and the ease of tuning its superconducting transition temperature, and therefore, it is one of the most studied Fe-based superconductors in experiments. In this review, we first introduced the different synthesis methods of high-quality FeSe superconductors in detail, and summarized their distinct characteristics. Furthermore, the superconducting critical parameters and basic physical properties of FeSe are listed, confirming its unconventional superconductivity. Moreover, the current application of FeSe superconductors is not only limited to the fields of alkali-metal batteries and photocatalysis, but also is expected to be used in industrial transmission lines.