6th Iberian Meeting of Colloids and Interfaces - RIC16: book of abstracts

info:eu-repo/semantics/publishedVersio

Nanoparticles in polyelectrolyte multilayer layer-by-layer (LbL) films and capsules : key enabling components of hybrid coatings

Originally regarded as auxiliary additives, nanoparticles have become important constituents of polyelectrolyte multilayers. They represent the key components to enhance mechanical properties, enable activation by laser light or ultrasound, construct anisotropic and multicompartment structures, and facilitate the development of novel sensors and movable particles. Here, we discuss an increasingly important role of inorganic nanoparticles in the layer-by-layer assembly—effectively leading to the construction of the so-called hybrid coatings. The principles of assembly are discussed together with the properties of nanoparticles and layer-by-layer polymeric assembly essential in building hybrid coatings. Applications and emerging trends in development of such novel materials are also identified

Spinterface Mediated Magnetic Properties of Co20Fe60B20/Alq3 Heterostructures

Organic semiconductors (OSCs) are suitable materials for spintronics applications as they form a spinterface when placed next to a ferromagnet, which in turn leads to novel functionalities. The evolution of spinterface can tune the global magnetic anisotropy, magnetization reversal, magnetization dynamics, etc. Planar tris-(8-hydroxyquinoline)aluminum (Alq3) OSC has shown tremendous potential for spintronics applications, thanks to its efficient spin-polarized current transport ability. Here, we establish the spinterface when the Alq3 molecules are deposited on amorphous ferromagnet Co20Fe60B20(CFB). The $\pi$-d hybridization in CFB/Alq3 enhances the coercive field and significantly modifies the shape and size of the magnetic domains. A $\sim$100% increase in uniaxial anisotropic energies and a reduction in magnetic damping are also evident owing to the strong interfacial hybridization

Hybrid spintronic materials:Growth, structure and properties

10.1016/j.pmatsci.2018.08.001Progress in Materials Science9927-10

Controlling the magnetism of adsorbed metal–organic molecules

Gaining control on the size or the direction of the magnetic moment of adsorbed metal–organic molecules constitutes an important step towards the realization of a surface-mounted molecular spin electronics. Such control can be gained by taking advantage of interactions of the molecule's magnetic moment with the environment. The paramagnetic moments of adsorbed metal- organic molecules, for example, can be controlled by the interaction with magnetically ordered substrates. Metalloporphyrins and -phthalocyanines display a quasi-planar geometry, allowing the central metal ion to interact with substrate electronic states. This can lead to magnetic coupling with a ferromagnetic or even antiferromagnetic substrate. The molecule–substrate coupling can be mediated and controlled by insertion layers such as oxygen atoms, graphene, or nonmagnetic metal layers. Control on the magnetic properties of adsorbed metalloporphyrins or -phthalocyanines can also be gained by on-surface chemical modification of the molecules. The magnetic moment or the magnetic coupling to ferromagnetic substrates can be changed by adsorption and thermal desorption of small molecules that interact with the fourfold-coordinated metal center via the remaining axial coordination site. Spin-crossover molecules, which possess a metastable spin state that can be switched by external stimuli such as temperature or light, are another promising class of candidates for control of magnetic properties. However, the immobilization of such molecules on a solid surface often results in a quench of the spin transition due to the interaction with the substrate. We present examples of Fe(II) spin-crossover complexes in direct contact with a solid surface that undergo a reversible spin-crossover transition as a function of temperature, by illumination with visible light, or can be switched by the tip of a scanning tunneling microscope