BCMaterials Fortnightly Seminar #55: Ariane Sagasti y Javier Alonso

ARIANE SAGASTI

(BCMATERIALS)

Two examples of functionalization of magnetoelastic resonant platforms for sensing purposes: zeolites and zinc oxide deposition processes

During the last years magnetoelastic resonant platforms have been reported to measure a wide range of environmental parameters like pressure, humidity, temperature and chemical or biological parameters. For this purpose the magnetoelastic material has to be covered with a chemically or biologically responsive layer that will be the responsible of detecting and trapping the agent desired to be detected. Because of the anchoring of the target molecules or species onto the responsive layer our device will show negative changes in the resonant frequency that will allow us to know the amount of molecules trapped. In this talk two different coating materials onto the magnetoelastic element will be presented, as well as the deposition process followed. First, the synthesis of three different zeolite coating (FAU, MFI and LTA) for volatile organic compound detection (xylene detection) will be presented. Second and in attempt to detect either inorganic salts or biological molecules as proteins, the study of different approaches to deposit an homogenous layer of zinc oxide using different methods will be explained.

 

JAVIER ALONSO

(BCMATERIALS)

Exchange Bias Effects in Iron Oxide-Based Nanoparticle Systems

The exploration of exchange bias (EB) on the nanoscale provides a novel approach to improving the anisotropic properties of magnetic nanoparticles for prospective applications in nanospintronics and nanomedicine. However, the physical origin of EB is not fully understood. Recent advances in chemical synthesis provide a unique opportunity to explore EB in a variety of iron oxide-based nanostructures ranging from core/shell to hollow and hybrid composite nanoparticles. Experimental and atomistic Monte Carlo studies have shed light on the roles of interface and surface spins in these nanosystems. This review paper aims to provide a thorough understanding of the EB and related phenomena in iron oxide-based nanoparticle systems, knowledge of which is essential to tune the anisotropic magnetic properties of exchange-coupled nanoparticle systems for potential applications.