Patterning of magnetic bimetallic coordination nanoparticles of Prussian blue derivatives by the Langmuir-Blodgett technique

Magnetic Hysteresis in a Monolayer of Oriented 6 nm CsNiCr Prussian Blue Analogue Nanocrystals

Prussian blue analogue nanocrystals of the Cs^INi^II[Cr^III(CN)₆] cubic network with 6 nm size were assembled as a single monolayer on highly organized pyrolytic graphite (HOPG). X-ray magnetic circular dichroism (XMCD) studies, at the Ni and Cr L_2,3 edges, reveal the presence of an easy plane of magnetization evidenced by an opening of the magnetic hysteresis loop (coercive field of ≈200 Oe) when the magnetic field, B, is at 60° relative to the normal to the substrate. The angular dependence of the X-ray natural linear dichroism (XNLD) reveals both an orientation of the nanocrystals on the substrate and an anisotropy of the electronic cloud of the Ni^II and Cr^III coordination sphere species belonging to the nanocrystals' surface. Ligand field multiplet (LFM) calculations that reproduce the experimental data are consistent with an elongated tetragonal distortion of surface Ni^II coordination sphere responsible for the magnetic behavior of monolayer.

Catalytic synergy of Au@CeO2–rGO nanohybrids for the reductive transformation of antibiotics and dyes

Changes in morphology of Au@CeO₂–rGO nanohybrids demonstrated synergistic effects of the ternary components for reductive transformation of antibiotics and dyes.

Spreading Films of Anthracene-Containing Gelator Molecules at the Air/Water Interface: Nanorod and Circularly Polarized Luminescence

Two enantiomeric gelator molecules containing anthracene moiety were assembled at the air/water interface and several new insights into the films of the gelator molecules were revealed. When these molecules were spread at the air/water interface, they formed the nanorod structured monolayers and could be subsequently transferred to the solid substrate. The formed Langmuir-Blodgett (LB) films showed both optical activity and circularly polarized luminescence (CPL) due to the chirality transfer upon assembling. The dissymmetric factors of the CPL in the LB films were enhanced nearly 5 times than those in gel systems. Through the formation of the organized nanofilms, the arrangement of the molecules become compact and the film showed enantioselectivity to chiral species, whereas the molecular solution could not.

Evolution of Nanoflowers and Nanospheres of Zinc Bisporphyrinate Tweezers at the Air/Water Interface

Although the sophisticated Langmuir and Langmuir-Blodgett (LB) techniques facilitate the fabrication of uniform ultrathin monolayer and films, they are also revealed as powerful tools for the bottom-up construction of the nanostructures through the air/water interface. In this paper, unique nanoflowers or nanospheres were constructed based on the synthesized m-phthalic diamide-linked zinc bisporphyrinate tweezers using the Langmuir and LB techniques. It was found that the two tweezer-type zinc bisporphyrinates could form stable two-dimensional spreading films at the air/water interface, which could be subsequently transferred onto solid substrates using the vertical lifting method. Atomic force microscopy (AFM) revealed that at the initial spreading stage, the compound formed flat disklike domains and then hierarchically evolved into nanoflowers or nanospheres upon compressing the floating film. Such nanostructures have not been reported before and cannot be fabricated using the other self-assembly methods.

Access to enhanced catalytic core–shell CuO–Pd nanoparticles for the organic transformations

This paper describes the biosynthesis of core–shell CuO–Pd nanocatalysts with the aid of a Cyperus rotundus rhizome extract.

Spontaneous Deposition of Prussian Blue on Multi-Walled Carbon Nanotubes and the Application in an Amperometric Biosensor

A simple method has been developed for the spontaneous deposition of Prussian blue (PB) particles from a solution containing only ferricyanide ions onto conducting substrates such as indium tin oxide glass, glassy carbon disk and carbon nanotube (CNT) materials. Formation of PB deposits was confirmed by ultraviolet-visible absorption spectrometry and electrochemical techniques. The surface morphology of the PB particles deposited on the substrates was examined by atomic force microscopy and scanning electron microscopy. CNT/PB composite modified glassy carbon electrodes exhibited an electrocatalytic property for hydrogen peroxide reduction. These modified electrodes exhibited a high sensitivity for electrocatalytic reduction of hydrogen peroxide at −0.05 V (vs. Ag|AgCl), probably due to the synergistic effect of CNT with PB. Then, CNT/PB modified electrodes were further developed as amperometric glucose biosensors. These biosensors offered a linear response to glucose concentration from 0.1 to 0.9 mM with good selectivity, high sensitivity of 0.102 A M⁻¹ cm⁻² and short response time (within 2 s) at a negative operation potential of −0.05 V (vs. Ag|AgCl). The detection limit was estimated to be 0.01 mM at a signal-to-noise ratio of 3.