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Despite the excellent properties of Pb(Zn1/3Nb2/3)O3-4.5PbTiO3 (PZN-4.5PT) single crystals, the greatest difficulty for their application on electronic devices is to make them to thin layers related to the difficulty to make them as ceramic materials. In this paper, we use the combined USAXS/SAXS/WAXS instrument at 9ID beamline at APS-ANL for in situ characterization of PZN-4.5PT inorganic perovskite nanoparticles thin films deposited on nanotextured silicon to understand the phase transitions and determine the observed microcrystals' structure. The sample was annealed from ambient to 1000°C. The results revealed structure changes in the nanoparticles' thin films which could be explained by the new phase that can be assigned to the Pb3(PO4)2-based component. The peak at 31° indicates the presence of the rhombohedral phase perovskites assigned to the nanoparticles. WAXS characterization permitted to identification of many transitions during thermal annealing like dehydration or dihydroxylation of phosphorus gel –OH bonds and internal water. [ABSTRACT FROM AUTHOR]

Photocatalytic reduction of O2 to generate H2O2 shows an excellent environment friendly nature and the controllable H2O2 concentrations and is found the prospect of applications in H2O2‐assisted redox. In this paper, MIL‐68(In) is chosen as a sacrifice precursor to construct a multi‐component photocatalyst of In2O3/In2S3/C by integrated in situ sulfidation and pyrolysis routes. The resulting In2O3/In2S3/C inherited the geometry of MIL‐68(In) and represents the hollow microtube with rough surface. The photocatalytic activity of the In2O3/In2S3/C in H2O2 generation is investigated systematically, and the contrast tests were conducted over the In2S3/MIL‐68 synthesized by in situ sulfidation but without subsequent pyrolysis, to explore the advantages of the In2O3/In2S3/C heterostructure. The best photocatalytic H2O2 evolution is observed by the In2O3/In2S3/C with a value of 934.6 μmol/L within 1 h, which is higher than that by In2S3/MIL‐68 and other previously reported photocatalysts. The photoelectrochemical analyses and ESR measurements clarify that contact heterojunction and matched band potentials are responsible for the effective separation of electrons and holes, and the O2·‐ are the main active species in the photocatalytic H2O2 evolution. The outstanding photocatalytic activity, structure stability, and the easily regulated H2O2 concentrations render the In2O3/In2S3/C the prospect applications in the H2O2‐assisted redox reactions. [ABSTRACT FROM AUTHOR]

In this paper, ZnO‐containing coatings were prepared on the surface of AZ31B magnesium alloy by a simple one‐step micro‐arc oxidation method using zinc gluconate as the zinc source. The microstructure, elemental distribution, phase composition and chemical composition of the coatings were analyzed by scanning electron microscopy (SEM), energy spectrometry (EDS), X‐ray diffractometry (XRD) and X‐ray photoelectron spectroscopy (XPS), potentiodynamic polarization tests and electrochemical impedance spectroscopy were carried out in simulated body fluids to study the corrosion behavior of the coatings. The results show that introducing Zn2+ into the coatings reduces the number of pores and changes the microstructure of the coatings, resulting in improving corrosion resistance. In addition, the corrosion current density of the coatings prepared by adding 6 g/L of zinc gluconate was approximately two orders of magnitude lower than that of the coatings prepared without adding zinc gluconate. [ABSTRACT FROM AUTHOR]

The biodeterioration of cultural heritage monuments is a worldwide phenomenon, closely linked to the presence of microorganisms and macroorganisms. Microbial colonization leads to physical, chemical damage and esthetic changes. Synthetic polymers, particularly acrylics, are often used to consolidate and protect monuments and artistic stone surfaces. To increase acrylics performances regarding to durability and antimicrobials' activity, nanoparticles (NPs) were added to polymers. In this study, silver NP was biosynthesized by Malva sylvestris aqueous extract. Furthermore, the in situ method was used for nanocomposite synthesis, which would be simplified the procedure of synthesis. For this, the precursors including the plant aqueous extract, AgNO3 solution and polymer were mixed, and nanocomposite was formed. The morphological characteristics of the obtained nanocomposite were determined using field emission scanning electron microscope (FESEM). The energy-dispersive X-ray (EDX) confirmed AgNPs existence in the composite. Next, the nanocomposite's antibacterial properties were tested on Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Cladosporium cladosporioides, Aspergillus niger, and Alternaria alternata. The antibacterial activity of bioengineered nanocomposite compared to acrylic polymer, alone. The results of antimicrobial experiments have shown that the number of bacterial and fungal cells was decreased by 1 logarithm in the polymer, and by 2 to 4 logarithms in the nanocomposite that the antimicrobial effect of latter was notably increased. This study was based on applying this nanocomposite to improve conservation strategies for stony cultural heritage. Further experiments should be performed to evaluate the efficacy of this nanocomposite on outdoor stony model. [ABSTRACT FROM AUTHOR]

In this paper, Al-CaB6 alloys were prepared by in situ melt reaction. The CaB6 particles through in situ growth are cubic with a regular shape, evenly distributed in the Al matrix. By edge-to-edge matching model’s calculation, mismatch between CaB6 particles and α-Al was ~2.34%, which is less than 6%, so CaB6 can serve as the core of α-Al nucleation. When the amount of CaB6 addition reaches 6 wt.%, hardness of the Al-CaB6 alloy reached 34.4 HV. Besides, CaB6-particle reinforced hypereutectic Al-Si composites were prepared, and the positive influence of CaB6 particles on microstructure and properties of hypereutectic Al-Si composites was studied. The CaB6 particles show significant effect on the modification of primary silicon. Owing to the addition of CaB6 particles, the hardness of hypereutectic Al-Si alloys increased and the hardness of Al-18Si-CaB6 reached 95.1 HV. The electrochemical test of the manufactured composites revealed that the corrosion resistance of Al-18Si-CaB6 composites improved as the amount of CaB6 particle content increased. This work serves as a reference for the investigation of Al and Al-Si composites reinforced with ceramic particles. [ABSTRACT FROM AUTHOR]

It is well-established that the structural, morphological and performance characteristics of nanoscale materials critically depend upon the dispersion state of the nanofillers that is, in turn, largely determined by the preparation protocol. In this report, we review synthetic strategies that capitalise on the in situ generation of nanoparticles on and within polymeric materials, an approach that relies on the chemical transformation of suitable precursors to functional nanoparticles synchronous with the build-up of the nanohybrid systems. This approach is distinctively different compared to standard preparation methods that exploit the dispersion of preformed nanoparticles within the macromolecular host and presents advantages in terms of time and cost effectiveness, environmental friendliness and the uniformity of the resulting composites. Notably, the in situ-generated nanoparticles tend to nucleate and grow on the active sites of the macromolecular chains, showing strong adhesion on the polymeric host. So far, this strategy has been explored in fabrics and membranes comprising metallic nanoparticles (silver, gold, platinum, copper, etc.) in relation to their antimicrobial and antifouling applications, while proof-of-concept demonstrations for carbon- and silica-based nanoparticles as well as titanium oxide-, layered double hydroxide-, hectorite-, lignin- and hydroxyapatite-based nanocomposites have been reported. The nanocomposites thus prepared are ideal candidates for a broad spectrum of applications such as water purification, environmental remediation, antimicrobial treatment, mechanical reinforcement, optical devices, etc. [ABSTRACT FROM AUTHOR]

The addition of nanostructures to polymeric materials allows for a direct interaction between polymeric chains and nanometric structures, resulting in a synergistic process through the physical (electrostatic forces) and chemical properties (bond formation) of constituents for the modification of their properties and potential cutting-edge materials. This study explores a novel in situ synthesis method for PDMS-%SiO2 nanoparticle composites with varying crosslinking degrees (PDMS:TEOS of 15:1, 10:1, and 5:1); particle concentrations (5%, 10%, and 15%); and sol-gel catalysts (acidic and alkaline). This investigation delves into the distinct physical and chemical properties of silicon nanoparticles synthesized under acidic (SiO2-a) and alkaline (SiO2-b) conditions. A characterization through Raman, FT-IR, and XPS analyses confirms particle size and agglomeration differences between both the SiO2-a and SiO2-b particles. Similar chemical environments, with TEOS and ethanol by-products, were detected for both systems. The results on polymer composites elucidate the successful incorporation of SiO2 nanoparticles into the PDMS matrix without altering the PDMS's chemical structure. However, the presence of nanoparticles did affect the relative intensities of specific vibrational modes over composites from −35% to 24% (Raman) and from −14% to 59% (FT-IR). The XPS results validate the presence of Si, O, and C in all composites, with significant variations in atomic proportions (C/Si and O/Si) and Si and C component analyses through deconvolution techniques. This study demonstrates the successful in situ synthesis of PDMS-SiO2 composites with tunable properties by controlling the sol-gel and crosslinking synthesis parameters. The findings provide valuable insights into the in situ synthesis methods of polymeric composite materials and their potential integration with polymer nanocomposite processing techniques. [ABSTRACT FROM AUTHOR]

The aerobic photooxidation of sulfides into sulfoxides in eco-friendly solvents, notably water, at room temperature, represents a significant interest in the domain of synthetic chemistry. This study introduces four highly stable hexadentate Ir(III) complexes: [Ir(fpqen)](PF6) (1), [Ir(btqen)](PF6) (2), [Ir(bmpqen)](PF6) (3), and [Ir(bnqen](PF6) (4) (where bfpqen is N,N′-bis(2-(4-fluorophenyl)quinolin-8-yl)ethane-1,2-diamine, btqen is N,N′-bis(2-(4-tolyl)quinolin-8-yl)ethane-1,2-diamine, bmpqen is N,N′-bis(2-(4-methoxyphenyl)quinolin-8-yl)ethane-1,2-diamine, and bnqen is N,N′-bis(2-naphthylquinolin-8-yl)ethane-1,2-diamine). These complexes were synthesized utilizing an in situ inter-ligand C-N cross-coupling photoreaction of the precursors [Ir(L)2(en)](PF6) (L is 2-(4-fluorophenyl)quinoline, (2-(4-tolyl)quinoline, 2-(4-methoxyphenyl)quinoline or 2-naphthylquinoline, and en is 1,2-diamine) under benign conditions. This methodology furnishes a valuable and complementary approach for the in situ generation of multidentate complexes through a post-coordination inter-ligand-coupling strategy under mild conditions. Moreover, these hexadentate Ir(III) complexes exhibit pronounced catalytic activity and chemo-selectivity toward the aerobic photooxidations of sulfides into sulfoxides in aqueous media at room temperature, offering a new avenue for the sustainable synthesis of sulfoxides. [ABSTRACT FROM AUTHOR]

Nowadays, due to the increasing number of diseases and injuries related to bone tissue, there is an acute problem of creating a material that could be incorporated into the bone tissue structure and contribute to accelerated bone regeneration. Such materials can be represented by a polymeric matrix that holds the material in the bone and an inorganic component that can be incorporated into the bone structure and promote accelerated bone regeneration. Therefore, in this work we investigated polyvinyl alcohol-based composite cryogels containing an in situ deposited inorganic filler, hydroxyapatite. The freezing temperature was varied during the synthesis process. The composition of the components was determined by infrared spectroscopy and the phase composition by X-ray phase analysis, from which it was found that the main phase of the composite is hydroxyapatite and that the particle size decreases with increasing freezing temperature. The elemental composition of the surface is dominated by carbon, oxygen, phosphorus and calcium; no impurities of other elements not typical for polyvinyl alcohol/ hydroxyapatite cryogels were found. Higher mechanical properties and melting points were observed at −15 °C. Cryogenic treatment parameters did not affect cell viability; however, cell viability was above 80% in all samples. [ABSTRACT FROM AUTHOR]