A comparative investigation of structural, magnetic and photocatalytic properties of pure, Ce-Ni and Cd-Ni co-doped BiFeO3 nanoparticles

Abstract

Bismuth ferrite, BiFeO3 (BFO) as well as Ce-Ni, Cd-Ni co-substituted BiFeO3 nanoparticles were prepared using the sol–gel route. XRD and Raman results show a structural phase transformation from rhombohedral (pristine BFO) to orthorhombic in the case of Bi0.94Cd0.06Fe0.94Ni0.06O3 (BCdFNO6), which implies that Cd substitution can induce the obvious transition of crystal structure while Ce substitution Bi0.94Ce0.06Fe0.94Ni0.06O3 (BCeFNO6) cannot. An apparent blue shift can be noted in all the substituted samples and with a reduction of the direct optical bandgap compared with the pristine BFO. The XPS findings show that Ce-Ni and Cd-Ni substitution increases the Fe3+ ions (Cd-Ni co-doped samples reveal the best outcomes), which would be evidence for reducing oxygen vacancies and improving magnetism. Cd-Ni co-substituted into BFO can improve magnetic properties because the ionic radii of Cd2+ ion are smaller than that of Bi3+ ion; moreover, intriguingly, the room temperature magnetic (M−H) hysteresis loops reveal the greatest saturation magnetization value in Cd-Ni co-substituted samples. The co-doped of Cd-Ni, has the greatest degradation activity 99.48 % of MB and 98.76 % of RhB would be successes after 90 min irradiation, which was raised by 9.49 %, 25 % of MB and 9.52 %, 26.92 % of RhB from that of the Ce-Ni co-doped and pristine BFO.