The properties of non‐oxide materials are continuously revealed, and their applications in the fields of ceramics, energy, and catalysis are increasingly extensive. Regardless of the traditional binary materials or the MAX phases, the preparation methods, which are environmentally friendly, efficient, economical, and easy to scale‐up, have always been the focus of attention. Molten salt synthesis has demonstrated unparalleled advantages in achieving non‐oxide materials. In addition, with the development of the process in molten salt synthesis, it also shows great potential in scale‐up production. In this review, the recent progress of molten salt synthesis in the preparation of binary non‐oxide and MAX phase is reviewed, as well as some novel processes. The reaction mechanisms and the influence of synthetic conditions for certain materials are discussed in detail. The paper is finalized with the discussion of the application prospect and future research trends of molten salt synthesis in non‐oxide materials.

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The application field of zirconium involves chemical, metallurgical, biological and nuclear industries due to its excellent properties. However, the uneconomical production process of zirconium at this stage has led to its high price. With the increasing demand for zirconium, the call for price reduction is becoming stronger. A review on zirconium preparation processes is provided in this paper with emphasis on electrolysis process, which has the potential to replace the traditional Kroll process. Electrolysis process can be classified into three types according to different zirconium sources: Molten salt electrolysis process, electrodeoxidation process and zirconium production from oxycarbide anode. The principle, flow, current achievements and barriers to industrial application of various electrolysis processes are discussed. The review is finalized with the suggestions for future research directions.

Electrochemical behavior of Zr(IV) in LiCl-KCl-ZrCl 4 molten salt on molybdenum electrode was systematically studied by a series of electrochemical techniques such as cyclic voltammetry, square wave voltammetry and chronopotentiometry. It was investigated that the Zr(IV) was first reduced to Zr(III) in this system, which is different from most studies in which Zr(IV) is first reduced to Zr (II). The activation energy of Zr(IV) converted to Zr(III) was calculated to be 24.6 kJ mol −1 by measuring the diffusion coefficients of Zr(IV) at 450 °C, 500 °C, and 550 °C. Through research, the nucleation of zirconium belongs to the progressive nucleation on molybdenum electrode in LiCl-KCl-ZrCl 4 (0.0359 mol L −1 ) at 500 °C at −3.0 V vs Cl 2 /Cl − . Constant current electrolysis (Current density 0.52 A cm −2 , duration 500 min) was carried out in LiCl-KCl-ZrCl 4 system and the electrolytic product was porous metallic zirconium. More importantly, it is found that the difference in decomposition potential between Zr(II) and Hf(II) is the largest by calculation and test compared with their trivalent and tetravalent states, and they may be separated by electrolysis, which provides a theoretical reference for the electrolytic preparation of nuclear grade zirconium.

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