Magnetism in a 2D Hybrid Ruddlesden-Popper Perovskite through Charge Redistribution Driven by an Organic Functional Spacer.

Two-dimensional Ruddlesden-Popper (RP) perovskites are emerging materials offering great synthetic versatility and remarkable features due to the tunability of their crystal structure. We present a novel strategy to provide magnetism in a 2D RP perovskite using histidine molecules as a spacer, which could induce charge rebalancing at the interface of the inorganic layer. We observe that the amide and imidazole groups are close to Pb ions. The interaction with the imidazole indicates that this functional group, possibly assisted by the carboxyl close to the vicinity of the amine terminal, is inducing charge rearrangement from Pb2+ to paramagnetic Pb3+ ions, resulting in a positive magnetic moment. This magnetized 2D hybrid perovskites can be classified as a novel class of promising materials showing a magnetic moment at their interface, which may result in intriguing physical properties due to a delicate balance between magnetism and a quantum well confinement effect in the inorganic layer.

Magnetoliposomes as model for signal transmission.

Liposomes containing magnetic nanoparticles (magnetoliposomes) have been extensively explored for targeted drug delivery. However, the magnetic effect of nanoparticles movement is also an attractive choice for the conduction of signals in communication systems at the nanoscale level because of the simple manipulation and efficient control. Here, we propose a model for the transmission of electrical and luminous signals taking advantage of magnetophoresis. The study involved three steps. Firstly, magnetite was synthesized and incorporated into fusogenic large unilamellar vesicles (LUVs) previously associated with a fluorescent label. Secondly, the fluorescent magnetite-containing LUVs delivered their contents to the giant unilamellar vesicles (GUVs), which were corroborated by magnetophoresis and fluorescence microscopy. In the third step, magnetophoresis of magnetic vesicles was used for the conduction of the luminous signal from a capillary to an optical fibre connected to a fluorescence detector. Also, the magnetophoresis effects on subsequent transmission of the electrochemical signal were demonstrated using magnetite associated with CTAB micelles modified with ferrocene. We glimpse that these magnetic supramolecular systems can be applied in micro- and nanoscale communication systems.