http://files.janapv.webnode.cz/200000097-8a03f8afdf/ex_bias_nano.pdf

Exchange bias in nanostructures

This review is focused on describing state-of-the-art synthetic routes for the preparation of magnetic nanoparticles useful for biomedical applications. In addition to this topic, we have also described in some detail some of the possible applications of magnetic nanoparticles in the field of biomedicine with special emphasis on showing the benefits of using nanoparticles. Finally, we have addressed some relevant findings on the importance of having well-defined synthetic routes to produce materials not only with similar physical features but also with similar crystallochemical characteristics.

The preparation of magnetic nanoparticles for applications in biomedicine : Biomedical applications of magnetic nanoparticles

Oxygen evolution reaction (OER) electrolysis, as an important reaction involved in water splitting and rechargeable metal-air batteries, has attracted increasing attention for clean energy generation and efficient energy storage. Nickel/iron (NiFe)-based compounds have been known as active OER catalysts since the last century, and renewed interest has been witnessed in recent years on developing advanced NiFe-based materials for better activity and stability. In this review, we present the early discovery and recent progress on NiFe-based OER electrocatalysts in terms of chemical properties, synthetic methodologies and catalytic performances. The advantages and disadvantages of each class of NiFe-based compounds are summarized, including NiFe alloys, electrodeposited films and layered double hydroxide nanoplates. Some mechanistic studies of the active phase of NiFe-based compounds are introduced and discussed to give insight into the nature of active catalytic sites, which could facilitate further improving NiFe based OER electrocatalysts. Finally, some applications of NiFe-based compounds for OER are described, including the development of an electrolyzer operating with a single AAA battery with voltage below 1.5 V and high performance rechargeable Zn-air batteries. 
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A mini review of NiFe-based materials as highly active oxygen evolution reaction electrocatalysts

Some of the most relevant finite-size and surface effects in the magnetic and transport properties of magnetic fine particles and granular solids are reviewed. The stability of the particle magnetization, superparamagnetic regime and the magnetic relaxation are discussed. New phenomena appearing due to interparticle interactions, such as the collective state and non-equilibrium dynamics, are presented. Surface anisotropy and disorder, spin-wave excitations, as well as the enhancements of the coercive field and particle magnetization are also reviewed. The competition of surface and finite-size effects to settle the magnetic behaviour is addressed. Finally, two of the most relevant phenomena in the transport properties of granular solids are summarized namely, giant magnetoresistance in granular heterogeneous alloys and Coulomb gap in insulating granular solids.

https://iopscience.iop.org/article/10.1088/0022-3727/35/6/201/pdf

R. H. Kodama

Papers

Surface Spin Disorder in NiFe_2O 4 Nanoparticles