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Herein, the catalytic performance of palladium nanoparticles grafted on the polymeric TSNH2 (Tentagel-S-NH2) resin was investigated for continuous-flow liquid-phase hydrogenation of two industrially relevant chemicals: 2-methyl-3-butyn-2-ol and nitrocyclohexane. We investigated the effect of process parameters such as temperature and pressure on PdTSNH2 activity and selectivity. Depending on the reaction conditions, well-dispersed PdNPs with average size of about 2 nm have shown very high flexibility in terms selectivity toward the desired products: 2-methyl-3-buten-2-ol or 2-methyl-2-butanol in the case of 2-methyl-3-butyn-2-ol hydrogenation and cyclohexanone oxime or cyclohexylamine as the main product in the case of nitrocyclohexane conversion. The optimal reaction conditions for 2-methyl-3-buten-2-ol formation were estimated at 25 °C and 5 bar, and in the case of cyclohexanone oxime formation at 40 °C and 10 bar. We demonstrated the general trend in the catalytic performance of 2.2 wt% Pd grafted on Tentagel-S-NH2. Independently of the hydrogenated substrate, the increase in conversion leads to decreased selectivity to 2-methyl-3-buten-2-ol and cyclohexanone oxime at the expense of increasing the selectivity to 2-methyl-2-butanol or cyclohexylamine. Graphic abstract

A novel conjugation of guar gum with xanthate groups via facile aqueous xanthation reaction has been reported. Density of grafted xanthate on guar gum product (GG-X) is as high as 4.4%, thus GG-X is conceivably characterized and confirmed by various spectrometric, electrochemical, thermogravimetric, and microscopic methods. Complexation of GG-X with numerous borderline and soft metal ions (e.g. Fe

A 44-year-old woman was admitted to hospital with end-stage renal failure, productive cough, and decreased exercise tolerance. She had owned nine cats, which resulted in long-term exposure (18 years) to silica-containing bentonite cat litter. High-resolution computed tomography of the chest showed micronodular lesions in the lungs, and mild mediastinal lymphadenopathy. A lung biopsy revealed multinucleated giant cells, some of which had birefringent material and Schaumann bodies. X-ray photoelectron spectroscopy revealed the presence of silicon in the lung biopsy specimen, as well as in the patient’s cat litter. The pulmonary condition was suggestive of sarcoid-like lung disease, rather than silicosis, sarcoidosis, or hypersensitivity pneumonitis, according to the clinicopathological findings. Renal failure appeared to be a result of chronic hypercalcemia due to extrarenal calcitriol overproduction in activated alveolar macrophages. Ultimately, the patient was diagnosed with sarcoid-like lung disease complicated by end-stage renal failure from exposure to bentonite cat litter. Therapy with steroids, in addition to elimination of the bentonite cat litter exposure, resulted in a significant improvement in the health condition. At a follow-up visit after 4 months, an almost complete resolution of the lung lesions and a significant improvement in renal function were observed.

WOS:000795749600001 Atomic layer deposition (ALD) has been considered as an efficient method to deposit high quality and uniform thin films of various electron transport materials for perovskite solar cells (PSCs). Here, the effect of deposition sequence in the ALD process of aluminum-doped zinc oxide (AZO) films on the performance and stability of PSCs is investigated. Particularly, the surface of AZO film is terminated by diethylzinc (DEZ)/H2O (AZO-1) or trimethylaluminum (TMA)/H2O pulse (AZO-2), and investigated with surface-sensitive X-ray photoelectron spectroscopy technique. It is observed that AZO-2 significantly enhances the thermal stability of the upcoming methylammonium lead iodide (MAPbI(3)) layer and facilitates charge transport at the interface as evidenced by photoluminescence spectroscopes and favorable interfacial band alignment. Finally, planar-type PSC with AZO-2 layer exhibits a champion power conversion efficiency of 18.09% with negligible hysteresis and retains 82% of the initial efficiency after aging for 100 h under ambient conditions (relative humidity 40 +/- 5%). These results highlight the importance of atomic layer engineering for developing efficient and stable PSCs.

The step-by-step growth of yttrium oxide layer was controlled in situ using X-ray photoelectron spectroscopy (XPS). The O/Y atomic concentration (AC) ratio in the surface layer of finally oxidized Y substrate was found to be equal to 1.48. The as-grown yttrium oxide layers were then analyzed ex situ using combination of Auger electron spectroscopy (AES), elastic-peak electron spectroscopy (EPES) and scanning electron microscopy (SEM) in order to characterize their surface chemical composition, electron transport phenomena and surface morphology. Prior to EPES measurements, the Y oxide surface was pre-sputtered by 3 kV argon ions, and the resulting AES-derived composition was found to be Y0.383O0.465C0.152 (O/Y AC ratio of 1.21). The SEM images revealed different surface morphology of sample before and after Ar sputtering. The oxide precipitates were observed on the top of un-sputtered Y oxide layer, whereas the oxide growth at the Ar ion-sputtered surface proceeded along defects lines normal to the layer plane. The inelastic mean free path (IMFP) characterizing electron transport was evaluated as a function of energy in the range of 0.5–2 keV from the EPES method. Two reference materials (Ni and Au) were used in these measurements. Experimental IMFPs determined for the Y0.383O0.465C0.152 and Y2O3 surface compositions, λ, were uncorrected for surface excitations and approximated by the simple function λ = kEp at electron energies E between 500 eV and 2000 eV, where k and p were fitted parameters. These values were also compared with IMFPs resulting from the TPP–2 M predictive equation for both oxide compositions. The fitted functions were found to be reasonably consistent with the measured and predicted IMFPs. In both cases, the average value of the mean percentage deviation from the fits varied between 5% and 37%. The IMFPs measured for Y0.383O0.465C0.152 surface composition were found to be similar to the IMFPs for Y2O3.

In search a hydrogen source, we synthesized TiO2-Cu-graphene composite photocatalyst for hydrogen evolution. The catalyst is a new and unique material as it consists of copper-decorated TiO2 particles covered tightly in graphene and obtained in a fluidized bed reactor. Both, reduction of copper from Cu(CH3COO) at the surface of TiO2 particles and covering of TiO2-Cu in graphene thin layer by Chemical Vapour Deposition (CVD) were performed subsequently in the flow reactor by manipulating the gas composition. Obtained photocatalysts were tested in regard to hydrogen generation from photo-induced water conversion with methanol as sacrificial agent. The hydrogen generation rate for the most active sample reached 2296.27 µmol H2 h−1 gcat−1. Combining experimental and computational approaches enabled to define the optimum combination of the synthesis parameters resulting in the highest photocatalytic activity for water splitting for green hydrogen production. The results indicate that the major factor affecting hydrogen production is temperature of the TiO2-Cu-graphene composite synthesis which in turn is inversely correlated to photoactivity.

Lithium titanium oxide (Li4Ti5O12) particles were surface-modified with 1–5% wt. of multi-walled carbon nanotubes (MWCNT) using a new low temperature method (LTM). Subsequent techniques have been applied to characterize all materials: X-ray powder diffraction (XRD), Raman and X-ray photoelectron (XPS) spectroscopy, scanning electron (SEM), transmission (STEM), and atomic force (AFM) microscopy. The selected materials have been subjected to preliminary electrochemical analysis. The effect of the synthesis conditions on the obtained series of LTO/1–5% wt. MWCNT nanocomposites was analyzed. X-ray diffraction showed that the crystal structure of LTO is not affected by the multi-walled carbon nanotubes (MWCNT) modification. Raman spectroscopy confirms the XRD results that the MWCNTs do not affect the LTO structure and all nanocomposites show similar levels of defects and/or degree of graphitization. The XPS measurements showed the most intense line at the binding energy of 284.5 eV, which corresponds to the C=C/C-C bonding in carbon atoms in the graphitic structure on the surface of the LTO material. Additionally, the peak at 285.3 eV was attributed to aliphatic structures, edges, and defects in the graphitic nanotube structure, whereas the peaks at 286.1, 287.6, 289.0 and 290.1 eV, correspond to C O, C O, HO-C=O, and OCOO, carbon atoms attached to different oxygen-containing moieties, respectively. CNTs were well distributed between LTO particles, as revealed by STEM observations. Single CNTs or agglomerates by joining LTO particles created cross-links for electron transfer. The relationship and effect between the structural and morphological analysis of spinel Li4Ti5O12 structure modified with carbon nanotubes was examined for the first time in this work. The performed preliminary electrochemical measurements revealed that the best electrochemical properties was obtained for LTO powder modified with 1%wt. of MWCNT. After 50 cycles of charge/discharge processes at the current rate of 1 C, the LTO/1%wt. MWCNT powder retained more than 98% of its specific capacity.

The effect of Pd doping on nano-Ni catalyst hydrogenation aptitude in sulcatone (6-methyl-5-hepten-2-one) hydrogenation was investigated. Obtained results demonstrated that the addition of non-catalytic amounts of Pd to the surface of parent Ni catalyst improves the activity to the extent that it surpassed the activity of 2.16 wt% Pd catalyst (model catalyst) at optimal reaction conditions in the flow hydrogenation of an unsaturated ketone. Pd doping improves hydrogen activation on the catalyst, which was found to be a rate-limiting step using kinetic isotopic measurements and theoretical calculations.

Anodic oxidation of VT1-0 titanium and E-125 zirconium alloy in aqueous electrolyte solutions based on H2SO4 and K4P2O7 was used to obtain oxide coatings composed of Zr/ZrO2, Ti/TiO2, and mixed oxide systems Ti/TinOm ∙ ZrxOy. It was shown that, depending on the electrolyte рН, the films contained from 0.17 to 2.1% wt. of zirconium. The catalytic activity of the synthesized coatings in the oxidation reaction of the methyl orange azo dye under UV irradiation was established. The process rate constants and synergy factors for the mixed systems were calculated.