Electrochemical behavior of Fe(II) in acetamide–urea–NaBr–KBr melt and magnetic properties of inductively codeposited Nd–Fe film

The electroreduction of Fe(II) and Nd(III) in MClx–acetamide–urea–NaBr–KBr were studied by cyclic voltammetry and chronoamperometry. The reduction of Fe(II) to Fe is an irreversible process, the value of αnα of the electrode reaction was calculated to be 0.31 and the diffusion coefficient of Fe(II) was calculated to be 9.53 × 10−7 cm2 s−1 at 343 K. Nd(III) cannot be reduced alone in urea melt, but Nd–Fe can be codeposited by induced codeposition. The composition of Nd–Fe film varies with the Nd(III)/Fe(II) molar ratio, at the potential of −1.25 V the maximum content of Nd in Nd–Fe film is 60.4 wt%. The morphology of Nd–Fe film was investigated by SEM and AFM. Nd–Fe film comprises of nanoparticles with the size about 100–200 nm. X-ray diffraction (XRD) shows it is amorphous. After heat-treatment at 1173 K the crystal Nd2Fe17 phase can be formed. The magnetic properties of the Nd–Fe films were determined using hysteresis loops, at 5 K the coercive field Hc of Nd (62.6 wt%)–Fe amorphous film is 1225 Oe, the remanent magnetization MR and the saturation magnetization MS are 5.15 and 15.80 emu g−1, respectively.