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We describe a study of the magneto-optical properties of Ag + -doped CdSe colloidal nanoplatelets (NPLs) that were grown using a novel doping technique. In this work, we used magnetic circularly polarized luminescence and magnetic circular dichroism spectroscopy to study light-induced magnetism for the first time in 2D solution-processed structures doped with nominally nonmagnetic Ag + impurities. The excitonic circular polarization (P X ) and the exciton Zeeman splitting (ΔE Z ) were recorded as a function of the magnetic field (B) and temperature (T). Both ΔE Z and P X have a Brillouin-function-like dependence on B and T, verifying the presence of paramagnetism in Ag + -doped CdSe NPLs. The observed light-induced magnetism is attributed to the transformation of nonmagnetic Ag + ions into Ag 2+ , which have a nonzero magnetic moment. This work points to the possibility of incorporating these nanoplatelets into spintronic devices, in which light can be used to control the spin injection.

Current polymeric transfer methods of 2D materials often bring about the presence of wrinkles, cracks, and polymer residue, limiting the quality of the transferred materials and performance of devices. Herein, we report a transfer approach combining pretreatment by liquid nitrogen and lithium ion intercalation with polymer composite of small molecules and polystyrene to achieve high-fidelity transfer of 2D transition metal dichalcogenides (TMDs) grown by chemical vapor deposition. In this method, the as-grown samples were pretreated by liquid nitrogen and lithium ion intercalation to weaken the bonding between the TMD and the substrate. A polymer composite incorporating small molecules, namely camphor or naphthalene, was used to increase the dissolution of the polymer film. These two processes work synergistically to enable nearly 100% transfer of monolayer TMDs virtually free of wrinkles, cracks, or organic residue with retained optical properties. Our technique can be generalized for the efficient and high quality transfer of other 2D materials.

The objective of the present work is to explore the ratio of polyoxometalate charge to size together with the effect of the cation in coordination assemblies. In this regard, 12-borotungstic acid as a Keggin-type polyoxometalate which has a high negative charge density and is very rare in hybrid categories is used toH 2 pydc = 2,6-pyridinedicarboxylic acid) under hydrothermal conditions and characterized by elemental analysis, FT-IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. Single crystal X-ray diffraction analyses show that complexes 1 and 2 feature a 2D hybrid coordination polymer which further expands to a 3D supramolecular network through a dense layer of water chains, while compound 3 exhibits a 3D hybrid inorganic-organic network through μ 2 -OH bridges. Compounds 4-6 are isostructural and each consist of tetramer units to construct cationic sheets where the POMs interconnect these sheets to make 3D covalent hybrid frameworks. Furthermore, a CSD survey was carried out on the cation and ligand roles in the structure formation.