Electrodeposition of Nd and Pr onto W from fluoride based melts

Abstract

Electrodeposition of neodymium and praseodymium metal from molten NdF3+PrF3+LiF+ 0.5wt.%Pr6O11+0.5wt.%Nd2O3 electrolytes on W was investigated using voltammetry at 1050 °C. The square wave voltammetry confirmed that Nd electrodeposition is a two-step reduction process: first, involving one electron exchange (Nd(III)→Nd(II)) and second, involving two electrons exchange (Nd(II)→Nd(0)). However, praseodymium deposition proceeds as an one-step process involving exchange of three electrons (Pr(III)→Pr(0)). Nd and Pr metals were electrodeposited applying potentiostatic mode. The working electrode surface was analyzed by X-ray diffraction after Nd and Pr co-deposition.

Elektrohemijsko taloženje neodijuma i prazeodijuma iz fluoridnog NdF3+PrF3+LiF+ 0.5wt.%Pr6O11+0.5wt.%Nd2O3 rastopa na W radnoj elektrodi ispitivano je pomoću voltametrijskih tehnika na 1050 °C. Voltametrija sa pravougaonim talasima (SWV, square wave voltammetry) potvrdila je da je elektrohemijsko taloženje Nd proces koji se odvija u dva koraka: prvi, uključuje razmenu od jednog elektrona (Nd(III) → Nd(II)) i drugi korak, uključuje razmenu dva elektrona (Nd(II) → Nd(0)). Međutim, taloženje prazeodijuma uključuje izmenu tri elektrona (Pr(III) → Pr(0)) u jednom koraku. Nd i Pr su elektrohemijski taloženi primenom potenciostatskog režima. Nakon elektrohemijskog taloženja Nd i Pr površina radne elektrode analizirana je rengensko-difrakcionom tehnikom.