Enhanced Supercapacitive and Magnetic Performances of Ho3+ Doped Iron Oxide Nanoparticles Prepared Through a Novel One-Pot Electro-Synthesis Method Publisher



Aghazadeh M¹ ; Karimzadeh I² ; Ganjali MR^{3, 4}
Source: Physica Status Solidi (A) Applications and Materials Science Published:2017

Abstract

A novel one-step electro-chemical synthesis platform is developed for the preparation of Ho3+ doped iron oxide nanoparticles (Ho-IONPs). In this procedure, Ho-IONPs are electro-synthesized from an additive-free aqueous solution of mixed Fe(NO3)3 · 9H2O, FeCl2 · 4H2O, and HoCl3· 6H2O with applying dc current density of 10 mA cm−2 for 30 min. The characterization data provided by X-ray diffraction (XRD), field emission electron microscopy (FE-SEM) and energy-dispersive X-ray (EDX) confirmed that the synthesized Ho-IONPs have composition of magnetite crystal structure doped with 20 wt.% Ho3+ cations and average particles size of about 10 nm. The electrochemical results obtained galvanostatic charge-discharge (GCD) tests showed that Ho-IONPs could provide specific capacitance as high as 222 F g−1 at discharging condition of 0.5 A g−1, and 95.6% capacity retention after 1000 GCD cycling, which confirmed the suitability of the electro-synthesized Ho-IONPs for use in supercapacitors. The results of vibrating sample magnetometer measurements confirmed better superparamagnetic behavior of Ho-IONPs (Mr = 0.14 emu g−1 and HCi = 2.37 G) as compared with pure IONPs (Mr = 0.95 emu g−1 and HCi = 14.62 G) resulting from their lower Mr and HCi values. Based on the obtained results, the developed electro-synthesis method is introduced as a facile procedure for the preparation of high performance metal ion doped magnetite nanoparticles. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.