The cathodic reduction mechanism of Hf(IV) ions in a fused NaCl–KCl–NaF–K₂HfF₆ salt system was studied in various NaF concentrations at 1073 K to obtain a purified dendritic Hf metal. The results of cyclic voltammetry and square wave voltammetry indicated that the reduction process comprised two steps of Hf(IV) → Hf(II) and Hf(II) → Hf at low NaF concentrations (0 < molar ratio of [F⁻Hf⁴⁺] ≤ 17.39) and one step of Hf(IV) → Hf at high NaF concentrations (17.39 < molar ratio of [F⁻/Hf⁴⁺] < 23.27). The structure and morphology of the deposits obtained in potentiostatic electrolysis in the one-step reduction process were analyzed and verified by X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectrometry. In the one-step reduction process, the disproportionation reaction between the Hf metal and Hf complex ions was inhibited, and a large dendrite Hf metal was achieved in molten salt electrorefining.

在1073 K的各种NaF浓度下，研究了熔融NaCl–KCl–NaF–K ₂ HfF ₆盐体系中Hf（IV）离子的阴极还原机理，以获得纯化的树枝状Hf金属。循环伏安法和方波伏安法的结果表明，在低NaF浓度下，还原过程包括Hf（IV）→Hf（II）和Hf（II）→Hf（0 <[F ^- Hf ^4+的摩尔比]≤17.39），并在高的NaF浓度（17.39 <[F的摩尔比的Hf（IV）→Hf中的一个步骤^- / HF ⁴⁺] <23.27）。通过X射线衍射，扫描电子显微镜和能量色散X射线光谱法分析和验证了一步还原过程中恒电位电解过程中获得的沉积物的结构和形态。在一步还原过程中，抑制了Hf金属与Hf络合物离子之间的歧化反应，并且在熔融盐电精炼中获得了大的枝状Hf金属。