Kelvin-probe measurements on ferromagnetic thin film electrodes coated with self-assembled monolayers of chiral molecules reveal that the electron penetration from the metal electrode into the chiral molecules depends on the ferromagnet’s magnetization direction and the molecules’ chirality. Electrostatic potential differences as large as 100 mV are observed. These changes arise from the applied oscillating electric field, which drives spin-dependent charge penetration from the ferromagnetic substrate to the chiral molecules. The enantiospecificity of the response is studied as a function of the magnetization strength, the magnetization direction, and the handedness and length of the chiral molecules. These new phenomena are rationalized in terms of the chiral-induced spin selectivity (CISS) effect, in which one spin orientation of electrons from the ferromagnet penetrates more easily into a chiral molecule than does the other orientation. The large potential changes (>kT at room temperature) manifested here imply that this phenomenon is important for spin transport in chiral spintronic devices and for magneto-electrochemistry of chiral molecules.

Owing to the superior properties of hybrid perovskite, it is possible to avoid some of the selective layers in perovksite solar cells (PSCs). One known example is the so-called hole-conductor-free PSCs, which were discovered at the beginning of the perovskite race. In this work, we introduce a thin MoO 3 layer, in HTM-free PSCs, at the perovskite/gold interface in order to investigate its influence on photovoltaic (PV) performance and to study the charge extraction behavior, recombination lifetime, and effect of hysteresis. Charge extraction measurements show that implementing a MoO 3 layer results in more charges to be extracted; this is beneficial to its PV performance. Intensity-modulated photovoltage spectroscopy shows two characteristic times at high and low frequency. The high frequency is dependent on light intensity and is related to the charge carrier recombination in the perovskite, whereas the low frequency is independent of light intensity and might be related to ion diffusion. Finally, it was observed that the MoO 3 forms a noncontinuous layer on the perovskite surface, which on the one hand improves its PV performance but on the other hand does not provide a physical barrier at this interface. This work provides new insights on HTM-free PSCs and the importance of their interfaces.

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Generally speaking, reaction platforms involving ferromagnetic surfaces, with a specific magnetic direction, are limited to the two dimensional regime, due to the nature of the magnetic phenomena. Here we show a method for preparing partially coated ferromagnetic microparticles with a distinct magnetic pole. This simple preparation method was presented previously [ 1 ] to demonstrate an application for enantiomeric separation. In this method article we show; A simple method to a-symmetrically manipulate particle surfaces. A generic way to synchronize a bare pole of ferromagnetic microparticles. A simple and generic enantiomer purification technique.