Here, ruthenium nanoparticles (1@RuNPs, 2@RuNPs, 3@RuNPs) stabilized with monodentate phosphoramidide ligands based on binanaphthyl skeletons with different steric properties (R: methyl(1), ethyl(2) and isopropyl(3)) were synthesized. To our knowledge, this study reports the first use of phosphoramidide ligands as stabilizers for ruthenium nanoparticles and systematically demonstrates their catalytic efficiency in hydrogen production via NaBH4 methanolysis. Their physical and chemical properties were elucidated using advanced characterization techniques, and accordingly, phosphoramidide ligands effectively stabilize ruthenium nanoparticles, producing particles with a narrow size distribution, small dimensions (1.36-1.41 nm) and a monodisperse structure. The catalytic performance during NaBH4 solvolysis was investigated, and 2@RuNPs catalyzed NaBH4 methanolysis 1.48 times faster than the others, reaching a hydrogen production rate of 452.9k mL H 2 /(gcat *min) in 10 s (k = 10 3 , HPR10sec). During kinetic studies for NaBH4 methanolysis, activation energies for those catalyzed by 1@RuNPs, 2@RuNPs, and 3@RuNPs were calculated as 19.80 +/- 0.53, 25.43 +/- 0.27, and 44.57 +/- 0.50 kJmol-1 , respectively.

This work presents the catalytic application of nanostructured nanorod (NR)- and nanowire (NW)-La2O3 catalysts systematically prepared by hydrothermal methods on hydrogen production from NaBH4 solvolysis reactions (hydrolysis/methanolysis). These fresh and spent nanostructured catalysts were characterized by advanced spectroscopic techniques. As a result of the solvolysis reactions of NaBH4 carried out in the presence of nanostructured La2O3 catalysts at 298 K, the methanolysis reaction and the NR-La2O3 catalyst were clearly prominent, with both 4.03 equivalents hydrogen and a hydrogen production rate of 6936 mLH2(gcat & sdot;min)- 1 in 0.5 min (HPR0.5m). According to the zero-order law kinetic model, the activation energy of NR-La2O3 was found to be 31.07 kJmol- 1. Storability tests showed that the NR-La2O3 catalyst had almost the initial activity even after 3 months. As a result, it was understood that the highly capable NR-La2O3 catalyst with its oxygen vacancies and adsorption capabilities could be a pioneer for many catalytic processes, especially NaBH4 methanolysis.

Catalyst design is of great importance for hydrogen production from solid hydrogen storage materials such as NaBH4. For this purpose, lanthanum-based La2O3 and La2O2CO3 nanowire catalysts were synthesized via a hydrothermal method, followed by calcination at different temperatures (700 degrees C and 500 degrees C, respectively) to obtain the desired crystalline phases. Their activities in NaBH4 solvolysis were then investigated. Accordingly, La2O2CO3 nanowire catalyst catalyzed NaBH4 methanolysis 3.4 times faster than the other reactions, exhibiting the highest hydrogen production rate at 0.5 min (HPR0.5m, 6939 mLH2/(gcat*min)) and equivalent H2 (4.03) values. Kinetic studies of NaBH4 methanolysis in the presence of the La2O2CO3 nanowire catalyst calculated the activation energy as 32.09 kJ/mol. Furthermore, even after 3 months of isolation, the reused La2O2CO3 nanowire catalyst retained 76.67% of its catalytic activity. All findings indicate that La2O3 and La2O2CO3 nanowire catalysts significantly increase hydrogen production efficiency, highlighting their potential for practical application in clean energy and hydrogen storage technologies.

In this study, which was carried out with priority given to the environment, CuNPs were tested as a phytocatalyst for dimethylamine-borane (Me2NHBH3) hydrolysis after being loaded in situ into three different OSS-replaced cements (CuNPs@OSS®CEM, OSS = Oil Seed Shells, hazelnut (HS), walnut (WS) and almond (AS) shells). These three catalysts with nearly monodisperse size were synthesized in situ through Me2NHBH3 hydrolysis in water at 25.0 ± 0.1 °C and characterized by advanced analysis. From TEM images, black CuNPs@HS®CEM and CuNPs@AS®CEM were calculated to have a unique monodisperse distribution in hexane and have particle sizes of 29.41 nm and 18.18 nm, respectively. Also, from the TEM image of CuNPs@WS®CEM, these nanoparticles were measured to be close to monodispersity and the average particle size was 26.77 ± 0.23 nm. Detailed kinetic studies were carried out on Me2NHBH3 hydrolysis using these three phytocatalysts and TON and TOF values of 24,896, 22,586 and 22,385 (for 50 h) and 498, 452 and 448 h− 1 were obtained for CuNPs@HS®CEM, CuNPs@WS®CEM and CuNPs@AS®CEM, respectively. In summary, this study encourages the use of these three CuNPs@OSS®CEMs with high activity on hydrogen production as building materials in another study. Synthesis of copper nanoparticles loaded on oilseed shells (OSS)-replaced cement. Use of oilseed shells (OSS) as agro-waste supporter for copper nanoparticles. Making CuNPs@OSS-replaced cement candidates for innovative hydrolysis of Me2NHBH3. In-depth characterization of oilseed shells (OSS) and their copper nanoparticles. Detailed kinetic studies of copper nanoparticles loaded on oilseed shells (OSS).

The extract of Glycyrrhiza glabra (licorice root), including the active compound glycyrrhizic acid (GZA), has garnered significant interest from researchers for its many use as a food sweetener. The research effort focuses on ecologically sustainable bio-hydrogen generation technology via green synthesis methods. This research includes, for the first time, the use of Glycyrrhiza glabra extract as bio-modification material for zinc oxide nanoflakes (ZnONFs) and hydrogen generation by catalytic NaBH4-methanolysis (SB-methanolysis) utilizing the synthesized nanoflakes. Detailed kinetic examinations were carried out on SB-methanolysis, revealing that the activation energy and lifetime of Glycyrrhiza glabra modified ZnONFs were 50.1 kJ/mol and about 134k mol H2 (mol Zn)- 1, respectively. The both chemical and physical structures of Glycyrrhiza glabra modified ZnONFs and the extract were characterized, and the average particle size of the nanoflakes was revealed to be 25.70 +/- 4.85 nm. Furthermore, it was understood from the SEM micrographs that average cluster size and thickness of Glycyrrhiza glabra modified ZnONFs were 8.29 +/- 2.91 mu m and 64.12 +/- 14.37 nm, respectively. XRD data showed that ZnONFs, consisting of an average of 73.069 % Zn metal, had a hexagonal wurtzite crystal structure. In conclusion, Glycyrrhiza glabra modified ZnONFs prepared by green synthesis technique were presented in this study as an ideal phytocatalyst candidate for hydrogen production with their amazing properties and high catalytic activities.

Recently, "Bacillus atrophaeus", which has a cell wall structure consisting of peptidoglycan layers, has attracted the attention of researchers due to its different usage areas. In particular, research focuses on the technology of obtaining bio‑hydrogen with various techniques. This research involves, for the first time, the use of the Bacillus atrophaeus bacteria as a bio-supporting material for monodisperse copper nanoparticles (CuNPs@Bacillus atrophaeus) and the manufacture of hydrogen through catalytic NaBH4-methanolysis (SB-methanolysis) in the presence of the resulting nanoparticles. Here, detailed kinetic studies were carried out during the SB-methanolysis by taking CuNPs and bacteria in varying amounts and at varying temperatures, and the activation energy and lifetime of monodisperse CuNPs@Bacillus atrophaeus was found to be 31.76 kJ mol-1 and 30,903 mol H2 (mol Cu)-1, respectively. The chemical and physical structure of the CuNPs@Bacillus atrophaeus was observed during the SB-methanolysis, so only detailed characterization of bacteria and monodisperse CuNPs@Bacillus atrophaeus was performed, and the particle size of the catalyst was calculated as 3.29 nm. The results showed that the monodisperse CuNPs@Bacillus atrophaeus, which has superior features and high catalytic activity, is a "clean", very well methanol-soluble, and quite surprising catalyst in terms of hydrogen production.

Aliphatic/aromatic nitrogen-substituted ligands have a very important role in ruthenium chemistry. Polydentate ligands with N-substituted pyridine rings are notable for their ability to easily modify the electronic and steric properties of ruthenium. In this study, the catalytic and biological activities of the [RuCl2(NNN)(CH3CN)] (NNN: 2,6-di(1H-pyrazol-3-yl)pyridine)) complex were examined for two different applications. Firstly, the superb Ru(II) complex was used to catalyze the methanolysis of NaBH4, and its initial rate was calculated as 69360 mLH(2)min(-1)g(cat)(-1). Secondly, the biological activities of the superb Ru(II) complex were examined. Accordingly, it was determined that this homogeneous complex showed anti-microbial activity on all bacteria used in the study, among the Gram-positive bacteria used in the study, the best result belongs to the Bacillus cereus EMC 19 bacterium with 8 mm, while among the Gram-negative bacteria, the best zone diameter belongs to the Pseudomonas aeruginosa DSM 50071 bacterium with 5 mm. However, it was observed that zone diameters varied between 8 mm and 3 mm. Compared to the control group, it was determined that 0.25 mg/mL concentration had 94.87%, 0.5 mg/mL concentration 96.10%, 1 mg/mL concentration 96.50%, and 2 mg/mL concentration 97.09% cytotoxic activity on the SH-SY5Y cell line. it was determined that all doses of the superb Ru(II) complex used in the study showed anti-cancer activity, but the anticancer activity shown at low doses was statistically more significant at the p < 0.05 level.

Recently, the single-celled green freshwater microalgae species " Chlorella vulgaris" " has attracted the attention of researchers due to its different usage areas. In particular, research focuses on the technology of obtaining bio-hydrogen with various techniques. This research involves, for the first time, the use of the microalga Chlorella vulgaris as a bio-supporting material for magnetite Fe3O4 3 O 4 nanoparticles (Fe3O4NPs@Chlorella 3 O 4 NPs@ Chlorella vulgaris) ) and the production of hydrogen through catalytic hydrolysis of NaBH4 4 (sodium borohydride, SB) in the presence of the resulting magnetite nanoparticles. Here, detailed kinetic studies were carried out during the SB-hydrolysis by taking magnetite Fe3O4NPs@Chlorella 3 O 4 NPs@ Chlorella vulgaris and SB in varying amounts and at varying temperatures, and the activation energy and lifetime of magnetite Fe3O4NPs@Chlorella 3 O 4 NPs@ Chlorella vulgaris was found to be 23.49 kJ mol-1- 1 and 93,280 mol H2 2 (mol Fe3O4)-1 , 3 O 4 )- 1 , respectively. No change in the chemical and physical structure of the biocatalyst was observed during the hydrolysis of SB, so only detailed characterization of microalgae and magnetite Fe3O4NPs@Chlorella 3 O 4 NPs@ Chlorella vulgaris was performed, and the particle size of the catalyst was calculated as 10.19 +/- 2.17 nm. The results showed that these Fe3O4NPs@Chlorella 3 O 4 NPs@ Chlorella vulgaris , , which can be easily separated magnetically and have high catalytic activity, are a "clean" and quite surprising catalyst in terms of hydrogen production.

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Different health management strategies may need to be implemented in different regions to cope with diseases. The current work aims to evaluate the relationship between air quality parameters and the number of new COVID-19 cases in two different geographical locations, namely Western Anatolia and Western Black Sea in Turkey. Principal component analysis (PCA) and regression model were utilized to describe the effect of environmental parameters (air quality and meteorological parameters) on the number of new COVID-19 cases. A big difference in the mean values for all air quality parameters has appeared between the two areas. Two regression models were developed and showed a significant relationship between the number of new cases and the selected environmental parameters. The results showed that wind speed, SO2, CO, NOX, and O-3 are not influential variable and does not affect the number of new cases of COVID-19 in the Western Black Sea area, while only wind speed, SO2, CO, NOX, and O-3 are influential parameters on the number of new cases in Western Anatolia. Although the environmental parameters behave differently in each region, these results revealed that the relationship between the air quality parameters and the number of new cases is significant.

This work covers the results of a detailed study on the in-situ formation and catalytic use of metal nanoparticles [Ru(0), Ni(0) and Cu(0)] stabilized on starch, a biodegradable and natural polymer, in the absence of a solvent by aiming to develop a green approach providing sustainable system for hydrogen production from the dehydrogenation of dimethylamine borane (DMAB) at about room temperature, 35.0 +/- 0.1 degrees C. All three metals were well-stabilized on the surface of starch with a particle size about 10.0 nm and highly active, long-lived in hydrogen production from the dehydrogenation of DMAB at 35.0 +/- 0.1 degrees C with an extraordinary initial TOF and TTON values of 173 h(-1) and 23000 TTON for Ru(0); 130 h(-1) and 13000 TTON for Cu(0) and 37 h(-1) and 4900 TTON for Ni(0) nanoparticles. Starch stabilized metal(0) nanoparticles could be isolated from the solution and characterized by UV-vis, XRD, TGA, TEM, SEM, EDX, and XPS.

Herein, the results of in-situ synthesis of four different metal(0) nanoparticles (Pd, Cu, Ru, and Ni) loaded on the surface of cellulose (MNPs@Cellulose) separately and their catalytic use in the solventless dimethylamine-borane (DMAB) dehydrogenation at 35.0 +/- 0.1 degrees C are reported. Based on the detailed kinetic studies on the solventless DMAB dehydrogenation catalyzed using MNPs@Cellulose, the following results were obtained: (i) Optimum metal loading percentage on the surface of cellulose was determined for Pd@Cellulose to be 4.0 wt.%Pd (152.39 h(-1)), Ni@Cellulose to be 3.0 wt.%Ni (59.09 h(-1)), Cu@Cellulose to be 3.0 wt.%Cu (55.45 h(-1)) and Ru@Cellulose to be 4.0 wt.%Ru (46.06 h(-1)) and by determining total turnover frequency values in average 10(th) minutes (TOF10), which provided the highest catalytic activity. (ii) The optimum amount of cellulose for each metal was found to be 50.0 mg for Pd, Cu, and Ru, and 40.0 mg for Ni. (iii) The Arrhenius activation energies were determined for each metal nanoparticles and calculated to be 69 +/- 2, 34 +/- 2, 35 +/- 2 and 42 +/- 2 kj.mol(-1) for Pd@Cellulose, Ni@Cellulose, Cu@Cellulose, and Ru@Cellulose, respectively.

Generally, white-flowering horse-chestnut seed (WFHC) found in roadsides, parks and gardens, which spills around and causes environmental pollution, is defined as waste-bio material. This study is quite remarkable as it gives WFHC a new field of usage and literally prioritizes the environment. Here, waste-bio WFHC was tested as supporter for tri-metallic RuNiPd nanoclusters in the eco-friendly dehydrogenation of dimethylamine-borane (DMAB). Core-shell-looking tri-metallic RuNiPd@WFHC, with 264.09 +/- 45.55 nm particle size, were in-situ synthesized throughout dehydrogenation of DMAB at 35.0 +/- 0.1 degrees C. The WFHC and tri-metallic Ru2.00Ni1.86Pd1.00@WFHC NCs were characterized by advanced analysis and their surface morphologies were studied in detail using adsorption models. The N2 adsorption-desorption and logarithmic-Freundlich plots indicated that surface morphologies have heterogeneous multi-layer and typical Type-III isotherm with meso-porous surfaces. Also, detailed kinetic studies were actualized on the dehydrogenation of DMAB catalyzed by tri-metallic Ru2.00Ni1.86Pd1.00@WFHC NCs with 158 h-1 TOF value.(c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

In this work, the findings of the work on the green dehydrogenation behavior of molten dimethylamine borane (DMAB) catalyzed by the precatalyst copper(II) acetylacetonate (Cu(acac)2) in solvent-free medium (green) at near room temperature (nRT, 30.0+0.1°C) were reported. Herein, a complete study has been presented, which includes the following steps: (i) synthesis and catalytic activity of Cu(0) NCats in solvent-free medium, (ii) determination of activation energy for Cu(0) NCats catalyzed green dehydrogenation of DMAB, (iii) demonstration of catalytic lifetime of Cu(0) NCats, (iv) test of isolability and reusability of Cu(0) NCats, (v) poisoning experiments using carbon disulfide on a per-active-copper-atom basis, (vii) characterization of Cu(0) NCats by UV-vis, XRD, XPS and TEM/HRTEM/TEM-EDX spectroscopies. In addition, ATR-FTIR and 11B NMR techniques were use to characterize the cyclic aminoborane product obtained as a result of dehydrogenation of dimethylamine-borane.

For the first time in this innovative study, microorganisms such as Bacillus simplex bacteria, mostly used in biological activity studies, are used as a bio-supporter agent of iron to release hydrogen from sodium borohydride hydrolysis at 25.0 +/- 0.1 degrees C. The goal is to investigate thoroughly sodium borohydride hydrolysis catalyzed by Fe2O3 nanoparticles impregnated on microorganism such as Bacillus simplex (BS) bacteria (Fe2O3@BS NPs) known with strong antibacterial properties, which makes innovative them a candidate for hydrolysis reaction. This study was focused on the preparation, identification, and catalytic use of biocatalyst-like Fe2O3@BS NPs for hydrogen release from the sodium borohydride hydrolysis at 25.0 +/- 0.1 degrees C. The characterization results made after and before hydrolysis reaction using by SEM/SEM-EDX, FT-IR, XRD, UVevis, XPS, DLS, ELS Zeta potential, ESR, and TEM techniques reveal the formation of highly active, stable, durable, and long-lived biocatalysts-like Fe2O3@BS NPs. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

In this study, we report a superior dehydrogenation catalyst for dimethylamine borane, which exhibited one of the best catalytic activities. The newly formed catalyst system contains well dispersed ruthenium-copper nanomaterials on reduced graphene oxide (3.86 +/- 0.47 nm), which was prepared by using the ultrasonic double reduction technique. The characterization of monodisperse ruthenium-copper alloy nanoparticles was performed using some advanced analytical methods such as TEM, HRTEM, XPS, Raman spectroscopic analysis. The experiments results revealed that the monodisperse ruthenium-copper alloy catalyst (RuCu@rGO) has one of the highest catalytic activity compared to previous studies, having a high turnover frequency value (256.70 h(-1)). The detailed kinetic parameters such as activation energy, enthalpy, and entropy values were also calculated for the dehydrogenation of dimethylamine borane at room temperature. Also, the results showed that the monodisperse RuCu@rGO catalyst has high durability and reusability as retained its 81% initial catalytic activity even after 4th runs for the dehydrogenation of dimethylamine borane. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

In this work, we reported a new catalyst consistent of graphene oxide (GO) - poly(N-vinyl-2-pyrrolidone) (PVP) hybrid supported ruthenium nanoparticles and called as Ru@GO-PVP. The GO-coupled PVP nanosheets were prepared with a new and straightforward pathway. The prepared Ru@GO-PVP nanocatalysts were characterized using some advanced analytic measurements such as XPS (X-ray photoelectron spectroscopy), XRD (X-ray diffraction), TEM/HRTEM (Transmission electron microscopy/high resolution transmission electron microscopy), Raman and ICP (Inductively coupled plasma). The mean particle size of the catalyst was found to be 2.09 nm, and this catalyst having small particle size showed one of the highest catalytic activities with a very high TOF value of 896.54 h(-1) in dehydrogenation of DMAB at room temperature. Therefore, the proposed hybrid and supported catalyst offer a new pathway to enhance the catalytic dehydrogenation of DMAB greatly, and this study presents a universal and powerful technique for such applications. (C) 2019 Elsevier B.V. All rights reserved.

Herein we report for the first time the preparation and catalytic use of the ceria supported manganese(0) nanoparticles in hydrogen generation from the hydrolysis of sodium borohydride. They are in situ formed from the reduction of manganese(II) ions on the surface of ceria nanopowders during the catalytic hydrolysis of sodium borohydride in aqueous solution at room temperature. Manganese(0) nanoparticles are isolated from the reaction solution by centrifugation and characterized by a combination of analytical techniques. Nanoceria supported manganese(0) nanoparticles are highly active and long-lived catalysts providing a turnover frequency of 417 h(-1) and 45,000 turnovers in hydrogen generation from the hydrolysis of sodium borohydride at 25.0 +/- 0.1 degrees C. They also have high durability as they retain 55% of their initial catalytic activity after the fifth cycle of hydrolysis providing a release of 4 equivalent H-2 gas per mol of sodium borohydride. The noticeable activity loss in successive runs of hydrolysis is attributed to the deactivation due to agglomeration. High activity and stability of ceria supported manganese(0) nanoparticles are ascribed to the unique nature of reducible cerium oxide. The formation of cerium(III) defects under catalytic conditions provides strong binding for the manganese(0) nano particles to oxide surface which makes the catalytic activity and stability favorable. Our report also includes the results of kinetic study of catalytic hydrolysis of sodium borohydride depending on the temperature, catalyst and substrate concentration. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.