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Understanding the structural and magnetic properties in layered hybrid organic-inorganic metal halide perovskites (HOIPs) is key for their design and integration in spin-electronic devices. Here, a systematic study is conducted on ten compounds to understand the effect of the transition metal (Cu2+, Mn2+, Co2+), organic spacer (alkyl- and aryl-ammonium), and perovskite phase (Ruddlesden-Popper and Dion-Jacobson) on the properties of these materials. Temperature-dependent Raman measurements show that the crystals’ structural phase transitions are triggered by the motional freedom of the organic cations as well as by the flexibility of the inorganic metal-halide lattice. In the case of Cu2+ HOIPs, an increase of the in-plane anisotropy and a reduction of the octahedra interlayer distance is found to change the behavior of the HOIP from that of a 2D ferromagnet to that of a quasi-3D antiferromagnet. Mn2+ HOIPs show inherent antiferromagnetic octahedra intralayer interactions and a phenomenologically rich magnetism, presenting spin-canting, spin-flop transitions, and metamagnetism controlled by the crystal anisotropy. Co2+ crystals with non-linked tetrahedra show a dominant paramagnetic behavior irrespective of the organic spacer and the perovskite phase. This study demonstrates that the chemical flexibility of HOIPs can be exploited to develop novel layered magnetic materials with tailored magnetic properties.

The exfoliation of layered magnetic materials generates atomically thin flakes characterized by an ultrahigh surface sensitivity, which makes their magnetic properties tunable via external stimuli, such as electrostatic gating and proximity effects. Another powerful approach to engineer magnetic materials is molecular functionalization, generating hybrid interfaces with tailored magnetic interactions, called spinterfaces. However, spinterface effects have not yet been explored on layered magnetic materials. Here, the emergence of spinterface effects is demonstrated at the interface between flakes of the prototypical layered magnetic metal Fe3GeTe2 and thin films of Co-phthalocyanine. Magnetotransport measurements show that the molecular layer induces a magnetic exchange bias in Fe3GeTe2, indicating that the unpaired spins in Co-phthalocyanine develop antiferromagnetic ordering and pin the magnetization reversal of Fe3GeTe2 via magnetic proximity. The effect is strongest for a Fe3GeTe2 thickness of 20 nm, for which the exchange bias field reaches −840 Oe at 10 K and is measurable up to ≈110 K. This value compares very favorably with previous exchange bias fields reported for Fe3GeTe2 in all-inorganic van der Waals heterostructures, demonstrating the potential of molecular functionalization to tailor the magnetism of van der Waals layered materials.

The successive self-nucleation and annealing (SSA) thermal fractionation technique has been applied for the first time to thermoplastic polyurethanes (TPUs). The changes in structure and morphology before and after SSA fractionation were monitored by Differential Scanning Calorimetry (DSC), in situ real-time Small and Wide-angle X-ray scattering synchrotron experiments (SAXS/WAXS) and Atomic Force Microscopy (AFM). SSA applies a series of successive cooling and heating runs to a self-nucleated sample that promotes the creation of a series of thermal fractions in the TPUs with a specific lamellar thicknesses and melting point distribution thanks to the multi-block structure of TPUs. The SSA fractionated samples experienced a general increase in lamellar thickness that has been revealed by both AFM and SAXS and a distribution of lamellar thickness estimated by DSC and AFM. The average lamellar thickness of SSA fractionated samples has been estimated by SAXS, AFM, and DSC. The values obtained are in quantitative agreement (within the errors involved in the techniques) when considering that phase segregation in the TPU samples has been promoted by crystallization. The refined crystalline structure obtained after SSA produced a number of clear WAXS reflections, as compared to the unfractionated materials, facilitating the determination of the TPUs crystallinity degree by WAXS.

Over the past decades, polymer mechanochemistry has focused on the development and application of advanced force application methods to better understand the mechanochemical response of mechanophores. In this regard, techniques such as ultrasonication and single-molecule force spectroscopy (SMFS) are used to activate and detect up to thousands of chemical events within a polymer single chain, allowing the researchers to probe the mechanochemical reactivity of these stress-responsive motifs. Here, the most recent contributions of the single-molecule force spectroscopy technique to this field are presented, putting emphasis on the fundamental parameters of the technique for triggering specific force responses and on the description of force–extension curves measured for single- and multi-mechanophore polymers. Moreover, new contributions of microscopy-based techniques in the field of polymer mechanochemistry, as well as the potential application of single-chain nanoparticles as mechanoresponsive materials, are highlighted.

A trigon structure formed by submonolayer gadolinium deposition onto Au(111) is revealed as a robust growth template for Co nanodot arrays. Scanning Tunneling Microscopy and X-Ray Magnetic Circular Dichroism measurements evidence that the Co nanoislands behave as independent magnetic entities with an out-of-plane easy axis of anisotropy and enhanced magnetic anisotropy values, as compared to other self-organized Co nanodot superlattices. The large strain induced by the lattice mismatch at the interface between Co and trigons is discussed as the main reason for the increased magnetic anisotropy of the nanoislands.

Microfluidic microdroplets have increasingly found application in biomolecular sensing as well as nanomaterials growth. More recently the synthesis of plasmonic nanostructures in microdroplets has led to surface-enhanced Raman spectroscopy (SERS)-based sensing applications. However, the study of nanoassembly in microdroplets has previously been hindered by the lack of on-chip characterization tools, particularly at early timescales. Enabled by a refractive index matching microdroplet formulation, dark-field spectroscopy is exploited to directly track the formation of nanometer-spaced gold nanoparticle assemblies in microdroplets. Measurements in flow provide millisecond time resolution through the assembly process, allowing identification of a regime where dimer formation dominates the dark-field scattering and SERS. Furthurmore, it is shown that small numbers of nanoparticles can be isolated in microdroplets, paving the way for simple high-yield assembly, isolation, and sorting of few nanoparticle structures.

Carbon nanotubes, gold nanorods, and silver nanoparticles can be transferred from water to organic solvents and back to water again by using polymeric ionic liquids (PILs) as vehicles (see scheme). The PILs are able to trap several nano-objects during their anion-exchange-induced precipitation in water. This reversible process provides a PIL/nano-object composite that is fully redispersible in organic solvents.