Publications de Andrzej Sienkiewicz

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Efficient inorganic UV shields, mostly based on refracting TiO2 particles, have dramatically changed the sun exposure habits. Unfortunately, health concerns have emerged from the pro-oxidant photocatalytic effect of UV-irradiated TiO2, which mediates toxic ...

Anionic Ln(iv) complexes were synthesised by tuning the reaction condition, demonstrating the possibility of accessing charged Pr(iv) complexes as a tool to manipulate the redox potential and therefore lead to more stable complexes. Structurally characterized Pr(IV) complexes are limited to four examples because the ligands and reaction conditions capable of stabilizing Pr(IV) remain elusive. Here we identify reaction conditions allowing the synthesis of Pr(IV) complexes that were originally thought difficu

The crystals of a novel family of rare-earth borate-nitrate compounds, Ln(7)(BO3)(3) (NO3)N3O (Ln = Pr, Nd), were grown at high-pressure in KAs flux and their crystal structure was determined. The new type of the crystalline structure consists of parallel ...

We employed electron spin resonance (ESR) technique in the investigation of a series of graphene flakes with different size distributions. Graphene oxide (GO) samples with three distinct size distributions were prepared by the Brodie method. Large flakes of similar to 2500 mu m(2), intermediate size flakes of similar to 1 mu m(2), and small ones of 500 nm(2) have been characterized by ESR in the 4-295 K temperature range. Already for GO flakes the magnetic response strongly varies with their size. Large GO

Radical-bridged diuranium complexes are desirable for their potential high exchange coupling and single molecule magnet (SMM) behavior, but remain rare. Here we report for the first time radical-bridged diuranium(IV) and diuranium(III) complexes. Reaction ...

The development of the molecular chemistry of lanthanides in the +4 oxidation state has encountered significant challenges due to their limited solution stability. Here, we demonstrate that combining siloxide ligands with oxo ligands leads to highly stable PrIV complexes. We report that the PrIII/PrIII oxo-bridged complex, [K(tol)K4{PrIII(OSiMe3)5}{PrIII(OSiMe3)4}(μ-O)], 4, can be easily prepared by controlled hydrolysis of the pentakis–siloxide complex [K2PrIII(OSiMe3)5]2, 2, followed by deprotonation. Oxi

Trinuclear molecular complexes of europium (II)and ytterbium(II) [Ln3{(Ph2SiO)2O}3(THF)6],1-Ln3L3(Ln = Euand Yb), supported by the dianionic tetraphenyl disiloxanediolateligand, were synthesized via protonolysis of the [Ln{N-(SiMe3)2}2(THF)2] complexes. In ...

We demonstrate that single crystals of methylammonium lead bromide (MAPbBr(3)) could be grown directly on vertically aligned carbon nanotube (VACNT) forests. The fast-growing MAPbBr3 single crystals engulfed the protogenetic inclusions in the form of indiv ...

Photoinduced charge separation in supramolecular aggregates of π‐conjugated molecules is a fundamental photophysical process, and a key criterion for the development of advanced organic electronics materials. Here, we report on the self‐assembly of novel l ...

We present a newly-developed microwave probe for performing sensitive high-field/multi-frequency electron spin resonance (ESR) measurements under high hydrostatic pressures. The system consists of a BeCu-made pressure-resistant vessel, which accommodates t ...

The performance of organic-inorganic metal halide perovskites-based (MHPs) photovoltaic devices critically depends on the design and material properties of the interface between the light-harvesting MHP layer and the electron transport layer (ETL). Therefo ...

Magnetic properties of a large assembly of ultrathin graphitic particles obtained by heavy sonication of graphite powder dispersed in N-methylpyrrolidone were measured by electron-spin resonance (ESR). The ESR signal was decomposed into one narrow and one ...

Spatial positioning of nanocrystal building blocks on a solid surface is a prerequisite for assembling individual nanoparticles into functional devices. Here, we report on the graphoepitaxial liquid-solid growth of nanowires of the photovoltaic compound CH ...

X-ray absorption spectroscopy is used to determine the local atomic structure around the iron atom from a soluble synthetic analogue of malaria pigment (hemozoin), cf. ferrimesoporphyrin IX of mesohematin anhydride, in the absence or presence of chloroquin ...

Various domains present the challenges of responding to stimuli in a specific manner, with the desired sensitivity or functionality, and only when required. Stimuli-responsive systems that are appropriately designed can effectively meet these challenges. H ...

The chemistry of lanthanides is limited to one electron transfer reactions due to the difficulty of accessing multiple oxidation states. Here we report that a redox-active ligand combining three siloxides with an arene ring in a tripodal ligand can stabili ...

We have attempted to prepare graphene samples by mechanical exfoliation of HOPG (highly oriented pyrolytic graphite) using scotch tape. Random testing of the flakes by AFM has shown in majority single layer graphene. Nevertheless, the presence of ultrathin ...

The uptake and movement of iron nanoparticles in elodea plants have been detected by the ESR method. This method is applied for the first time for the monitoring of the translocation, movement and uptake iron nanoparticles in plant organs. Exposition of st ...

This is a comparative study of photolytic degradation under exposure to UV254 nm and solar-simulator irradiation of a mixture of eight equally concentrated relevant micropollutants (atenolol, benzotriazole, clarithromycin, gabapentin, methylbenzotriazole, metformin, metoprolol and primidone; 2 µM of each compound) in the presence of H2O2 and Fe(II) in ultrapure water, Lake Geneva water, and effluent from a wastewater treatment plant (WWTP). The results indicate that the oxidation rate increased in the prese

Andrzej Sienkiewicz

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Cerium oxide nanoparticles, combining antioxidant and UV shielding properties, prevent UV-induced cell damage and mutagenesis

Accessing homoleptic neutral and anionic five-coordinate Pr(iv) siloxide complexes

High-Pressure Synthesis of Rare-Earth Borate-Nitrate Crystals for Second Harmonic Generation

Size dependence of the magnetic response of graphite oxide and graphene flakes - an electron spin resonance study

Assembling diuranium complexes in different states of charge with a bridging redox-active ligand

Synthesis and Properties of Stable Oxo-Bridged Dinuclear Pr IV Complexes

Structure and Reactivity of Polynuclear Divalent Lanthanide Disiloxanediolate Complexes br

Three-Dimensionally Enlarged Photoelectrodes by a Protogenetic Inclusion of Vertically Aligned Carbon Nanotubes into CH3NH3PbBr3 Single Crystals

Long‐Lived Photocharges in Supramoelcular Polymers of Low‐Bandgap Chromophores

Continuous-wave far-infrared ESR spectrometer for high-pressure measurements

Light-induced charge transfer at the CH3NH3PbI3/TiO2 interface-a low-temperature photo-electron paramagnetic resonance assay

Magnetism in nanoscale graphite flakes as seen via electron spin resonance

Controlled growth of CH3NH3PbI3 nanowires in arrays of open nanofluidic channels

Understanding Chloroquine Action at the Molecular Level in Antimalarial Therapy: X-ray Absorption Studies in Dimethyl Sulfoxide Solution

Light-responsive polymer nanoreactors: a source of reactive oxygen species on demand

Isolation and redox reactivity of cerium complexes in four redox states

Towards electron spin resonance of mechanically exfoliated graphene

Uptake and intracellular trafficking of superparamagnetic iron oxide nanoparticles (SPIONs) in plants

Degradation of Eight Relevant Micropollutants in Different Water Matrices by Neutral Photo-Fenton Process under UV254 and Simulated Solar Light Irradiation – a comparative study

Comparative behavior of relevant micropollutants in different water matrices by uv254 and simulated solar light irradiation and neutral photo-fenton process