The domain wall motion in magnetic nanoparticles is a useful parameter of study. The subject of this research is to study of the phenomenon of discontinuous domain wall motion, or the Barkhausen Effect in magnetic nanoparticles. In this work hematite (Fe2O3) nanoparticles have been synthesized using sol-gel auto-combustion and characterized using X-ray diffraction, Field emission scanning electron microscopy (FESEM), Transmission electron microscope (TEM) and Vibrating sample magnetometer (VSM) for crystal structure, morphology, shape, size and magnetic properties respectively. The FESEM and TEM results show that the particles are spherical in nature and average size is 60nm that is suitable for domain walls and barkhuasen effect. The VSM results show high coercivity 175 Oe and low saturation magnetization due to domain wall pinning and barkhausen effect. The size and magnetic properties reveals the existence of domain walls in the synthesized sample. The magnetic properties confirm the energy losses due to domain wall pinning, discontinuous domain rotation or barkhausen effect during magnetization which is useful for oil-water interfacial tension reduction and viscosity of oil. The high surface charge of magnetic nanoparticles and adsorption at the rock surface is useful for wettability alteration of rocks.

Even though the application of nanoparticles (NPs) in enhanced oil recovery (EOR) has been reported, but the development of different novel and efficient materials and their potential in EOR still need to explore. In this work, zinc nitride (Zn3N2) were developed and explored for enhanced oil recovery. Zinc nitride (Zn3N2) nanoparticles with triangular shape morphology were synthesized using sol-gel auto combustion method. The prepared NPs were characterized using X-ray diffraction and Field emission scanning electron microscopy for crystal structure, shape and size. The results reveal the formation of Zn3N2 triangular shape particles. Zn3N2 nanofluids of different concentrations were prepared and their effect on oil-water interfacial tension (IFT) under electromagnetic waves (EM) was investigated. The reduction in IFT was observed by introducing nanoparticles. It was found that Zn3N2 nanofluid under EM waves can bring an additional reduction in IFT. The value of IFT at 0.1 wt % of Zn3N2 under EM waves of frequency 2.2 MHz was 0.55 mN/m which is 75 % reduction.