Electrochemical fabrication of praseodymium cations doped iron oxide nanoparticles with enhanced charge storage and magnetic capabilities

Abstract

Pr3+ doped iron oxide nanoparticles (Pr-IONPs) are fabricated through a facile one-pot electro-synthesis method. In this procedure, Pr-IONPs are electro-deposited from an additive-free mixed aqueous solution of iron(III) nitrate, iron(II) chloride and praseodymium chloride salts with applying direct current of 10 mA cm−2 for 30 min. The analysis results obtained from X-ray diffraction, field emission electron microscopy and energy-dispersive X-ray showed that the deposited Pr-IONPs sample is composed of magnetite nanoparticles with an average size of 20 nm, and had 15 wt% Pr3+ in its structure. The electrochemical data provided by galvanostatic charge–discharge tests showed that Pr3+ doped iron oxide working electrode is enable to exhibit specific capacitances (Cs) values as high as 221, 194, 171, 139, 112, 94 and 82 F g−1 at the scan rates of 2, 5, 10, 20, 50, 75 and 100 mV s−1, which are ~ 20% higher than those of undoped electrode with Cs values of 181, 159, 140, 112, 92, 83 and 68 F g−1 at the scan rates of 2, 5, 10, 20, 50 and 100 mV s−1, respectively. These results proved the suitability of the electro-synthesized Pr3+ doped Fe3O4 NPs for use in supercapacitors. Furthermore, the results of vibrating sample magnetometer measurements revealed that Pr-IONPs have better superparamagnetic and lower Mr and Hci values (i.e. Mr = 0.13 emu g−1 and H Ci = 2.37 G) as compared with pure IONPs (Mr = 0.95 emu g−1 and H Ci = 14.62 G). Based on the obtained data, the developed electro-synthesis method is introduced as a facile synthetic method for the fabrication of high performance metal ion doped magnetite nanoparticles.