Abdullah Alqudami | Searcharxiv

arXiv2006

Fluorescence from metallic silver and iron nanoparticles prepared by exploding wire technique

The observation of intense visible fluorescence from silver and iron nanoparticles in different solution phases and surface capping is reported here. Metallic silver and iron nanoparticles were obtained by exploding pure silver and iron wires in pure water. Bovine serum albumin protein adsorption on the silver nanoparticles showed an enhanced fluorescence. The presence of poly-vinyl pyrrolidone polymer in the exploding medium resulted in a stabilized growth of iron nanoparticles with enhanced fluorescence intensity. The fluorescence was found to be surface /interface dependant. The fluorescence is attributed to electronic transitions among characteristic interface energy bands. The magnetic nature of iron nanoparticles was confirmed from the hysteresis measurements.

cond-mat.mtrl-sci↗

arXiv2006

Magnetic properties of iron nanoparticles prepared by exploding wire technique

Nanoparticles of iron were prepared in distilled water using very thin iron wires and sheets, by the electro-exploding wire technique. Transmission electron microscopy reveals the size of the nanoparticles to be in the range 10 to 50 nm. However, particles of different sizes can be segregated by using ultrahigh centrifuge. X-ray diffraction studies confirm the presence of the cubic phase of iron. These iron nanoparticles were found to exhibit fluorescence in the visible region in contrast to the normal bulk material. The room temperature hysteresis measurements upto a field of 1.0 tesla were performed on a suspension of iron particles in the solution as well as in the powders obtained by filtration. The hysteresis loops indicate that the particles are superparamagnetic in nature. The saturation magnetizations was ~ 60 emu / gm. As these iron particles are very sensitive to oxygen a coating of non-magnetic iron oxide tends to form around the particles giving it a core - shell structure. The core particle size is estimated theoretically from the magnetization measurements. Suspensions of iron nanoparticles in water have been proposed to be used as an effective decontaminant for ground water.

cond-mat.mtrl-sci↗