Joanna Wojciechowska

Bio: Joanna Wojciechowska is an academic researcher from Lodz University of Technology. The author has contributed to research in topics: Nanoparticle & Particle size. The author has an hindex of 1, co-authored 1 publications receiving 7 citations.

Solar Light Induced Photon-Assisted Synthesis of TiO₂ Supported Highly Dispersed Ru Nanoparticle Catalysts.

Abstract: Ru/TiO₂ are promising heterogeneous catalysts in different key-reactions taking place in the catalytic conversion of biomass towards fuel additives, biofuels, or biochemicals. TiO₂ supported highly dispersed nanometric-size metallic Ru catalysts were prepared at room temperature via a solar light induced photon-assisted one-step synthesis in liquid phase, far smaller Ru nanoparticles with sharper size distribution being synthesized when compared to the catalysts that were prepared by impregnation with thermal reduction in hydrogen. The underlying strategy is based on the redox photoactivity of the TiO₂ semi-conductor support under solar light for allowing the reduction of metal ions pre-adsorbed at the host surface by photogenerated electrons from the conduction band of the semi-conductor in order to get a fine control in terms of size distribution and dispersion, with no need of chemical reductant, final thermal treatment, or external hydrogen. Whether acetylacetonate or chloride was used as precursor, 0.6 nm sub-nanometric metallic Ru particles were synthesized on TiO₂ with a sharp size distribution at a low loading of 0.5 wt.%. Using the chloride precursor was necessary for preparing Ru/TiO₂ catalysts with a 0.8 nm sub-nanometric mean particle size at 5 wt.% loading, achieved in basic conditions for benefitting from the enhanced adsorption between the positively-charged chloro-complexes and the negatively-charged TiO₂ surface. Remarkably, within the 0.5⁻5 wt.% range, the Ru content had only a slight influence on the sub-nanometric particle size distribution, thanks to the implementation of suitable photo-assisted synthesis conditions. We demonstrated further that a fine control of the metal Ru nanoparticle size on the TiO₂ support was possible via a controlled nanocluster growth under irradiation, while the nanoparticles revealed a good resistance to thermal sintering.

Ru nanoclusters confined in porous organic cages for catalytic hydrolysis of ammonia borane and tandem hydrogenation reaction.

Abstract: The fabrication of narrow-sized metal nanoclusters for heterogeneous catalysis has attracted widespread research attention. Nevertheless, it is still a significant challenge to fabricate highly dispersed metal-nanocluster-based catalysts with high activity and stability. In this study, 1,3,5-benzenetricarboxylate and 1,2-diaminocyclohexane were used as precursors to fabricate porous organic cages (POCs), CC3-R. CC3-R exhibited a high specific surface area and a microporous–mesoporous structure. In addition, ultrafine Ru nanoclusters were successfully encapsulated in CC3-R with high dispersion via impregnation and subsequent reduction, affording Ru nanoclusters with a precisely controlled size of ∼0.65 nm. As-obtained Ru(1.45%)@CC3-R exhibited significantly enhanced catalytic activities toward the hydrolysis of ammonia borane (AB) and exhibited high conversion and selectivity for the tandem hydrogenation of nitroarenes and hydrogenation of quinoline in water under mild conditions. In addition, the Ru(1.45%)@CC3-R catalyst exhibited high stability and good recyclability. This study should provide a novel strategy for fabricating highly dispersed ultrafine nanocluster-based catalysts for various catalysis applications.

Advances In The Chemistry of The Coordination Compounds

Abstract: basic scientific contributions in the field of pharmacology. This volume covers 15 scientific subjects of major interest. The basic scientific principles of pharmacology rather than the use of drugs as therapeutic agents is stressed throughout. The introductory chapter by Gaddum tracing the growth of pharmacology in Edinburgh is followed by the highlights of pharmacology in China, India and Central Europe. These brief reviews are entirely inadequate and serve only to give adequate bibliographies of the original papers. Chapters are included on the biochemical aspects of drug action, structure-activity relationships, mechanisms of drug absorption and excretion with reference to the central nervous system, drug biotransformation, nervous transmission in the invertebrates, parasite chemotherapy, central depressants, renal pharmacology and pharmacological control of adrenal and gonadal secretion. Maickel and Weissbach discuss the relatively new techniques of spectrophotofluorometry, gas-liquid chromatography and tritium gas exposure labeling and have compiled a useful list of references regarding chemical and biochemical assay techniques. The review of reviews by Chauncey Leake is highly recommended. The editors of this book are to be congratulated for this valuable addition to current pharmacological literature. This volume is a collection of 76 papers and lectures presented by participants from 17 nations at the Proceedings of the Sixth International Conference on Coordination Chemistry held at Wayne State University in the summer of 1961. Approximately half of these papers are of a purely physical-chemical nature and often do little more than present tables of raw experimental data. Very little effort is made to correlate these experimental results with broader aspects of coordination chemistry which is, after all, the main value of such a conference. Furthermore, there is no apparent order to the presentation of the papers and the general effect is that of a bound collection of articles chosen at random from the chemical literature. In spite of these shortcomings, there are many pearls of interesting information scattered throughout the pages of this book. A useful reference work could have resulted if an exhaustive subject index had been included. The lack of any subject index whatsoever seems inexcusable. The Ciba Foundation and the Editors are to be congratulated for publishing yet one more of their stimulating symposia which will be widely read. The symposium is divided into two parts. The first part, in which papers were presented and discussions held before an invited audience, involves current problems in theoretical pharmacology, such as enzymes as primary points …

Carbon-based ruthenium nanomaterial-based electroanalytical sensors for the detection of anticancer drug Idarubicin.

Abstract: In this work, a novel nanosensing platform was suggested based on ruthenium for the sensitive determination of Idarubicin anticancer drugs. Ruthenium/Vulcan carbon-based nanoparticles were synthesized ultrasonication method and then characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The mean particle size of the nanoparticles calculated by the TEM analysis was found to be 1.98 nm ± 0.29 nm, and the Ru nanoparticles were mostly dispersed on the support material. Glassy carbon electrode (GCE) surface was modified with Ruthenium/Vulcan carbon-based nanomaterials (Ru@VC), and characterization of the nanosensor was performed using electrochemical impedance spectroscopy and cyclic voltammetry. The limit of detection (LOD) and limit of quantification (LOQ) values were found as 9.25 × 10–9 M and 2.8 × 10–8 M in buffer samples. To demonstrate the applicability and validity of developed nanosensor, it was used for the determination of Idarubicin in Idamen® IV (10 mg/10 mL vial) and human serum sample. The results of recovery studies showed that the Ru@VC/GCE nanosensor was free from excipient interferences in the dosage forms of injection, and it can be successfully applied to biological samples.

Experimental and Theoretical Advances on Single Atom and Atomic Cluster‐Decorated Low‐Dimensional Platforms towards Superior Electrocatalysts

Abstract: The fundamental relationship between structure and properties, which is called “structure‐property”, plays a vital role in the rational designing of high‐performance catalysts for diverse electrocatalytic applications. Low‐dimensional (LD) nanomaterials, including 0D, 1D, 2D materials, combined with low‐nuclearity metal atoms, ranging from single atoms to subnanometer clusters, are currently emerging as rising star nanoarchitectures for heterogeneous catalysis due to their well‐defined active sites and unbeatable metal utilization efficiencies. In this work, a comprehensive experimental and theoretical review is provided on the recent development of single atom and atomic cluster‐decorated LD platforms towards some typical clean energy reactions, such as water‐splitting, nitrogen fixation, and carbon dioxide reduction reactions. The upmost attractive structural properties, advanced characterization techniques, and theoretical principles of these low‐nuclearity electrocatalysts as well as their applications in key electrochemical energy devices are also elegantly discussed.

Hydrodeoxygenation of lignin derived phenolics over a hydrous ruthenium oxide based catalyst(s): role of surface water molecules and acidity of the support

Abstract: The synthesis of efficient and engineered noble metal catalysts for selective conversion of waste renewable lignin to valuable chemical building blocks is crucial for the economic viability of current biorefineries. Motivated by the water effect in promoting catalytic activity, hydrous ruthenium oxide (HRO) incorporating acidic systems (H-ZSM5, HY zeolite, γ-Al2O3, and SiO2) were investigated for selective hydrodeoxygenation of lignin-derived phenols in the aqueous phase. The results indicated that the hydrous form (surface bonded water molecules) of ruthenium and high acidity of the support promote the hydrogenolysis activity of the as-prepared catalysts and increase the yield of alkylated cyclohexanols. Among all catalysts, HRO@Y showed the best performance and afforded the highest selectivity to cyclohexanols. Intensive catalyst characterization demonstrated that in situ metal formation, a large number of acid sites, good metal dispersion, and high adsorption capacity of HRO@Y for polar fractions were responsible for the efficient activity. Water considerably improved the selective hydrodeoxygenation activity of the catalyst by promoting hydrogenation and demethoxylation and hindering dehydration.