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Abstract Porous In 2 O 3 nanoplates with polycrystalline structure (pp-In 2 O 3 NPs) and single-crystalline structure (ps-In 2 O 3 NPs) were synthesized through a facile solvothermal combined with a post calcination process. The gas sensing performance of the In 2 O 3 nanoplates with different crystallinity and porosity was investigated. Compared with the pp-In 2 O 3 nanoplates, the ps-In 2 O 3 nanoplates exhibited significantly enhanced gas sensitivity and selectivity towards triethylamine (TEA). The enhancement of the gas response of the ps-In 2 O 3 NPs can be attributed to the larger pore size and single-crystalline structure. Larger pore size can facilitate the target gas to diffuse into the inner surface of the sensing materials and increase the contacting chances of target gas and surface adsorbed oxygen species, while single-crystalline structure can decrease a part of grain boundary junction barrier and enhance the conductivity of the sensing film. This work would be important for further understanding the gas sensing mechanism and developing high promising In 2 O 3 gas-sensing materials. Graphical abstract Image 1 Highlights • Porous single-crystalline and polycrystalline In 2 O 3 nanoplates were controllable prepared. • The morphology and structure of the products were analyzed thoroughly. • The ps-In 2 O 3 nanoplates exhibited enhanced gas sensing performance to triethylamine. • The porous and single-crystalline structure contributed to the sensing properties. [ABSTRACT FROM AUTHOR]

Abstract: Hematite (α-Fe2O3) nanostructures with different morphologies have been synthesized by a simple ethylene glycol (EG)/H2O system using FeCl3 and urea as raw materials without adding any additives. Structure and morphology of the products were characterized by powder X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results indicated that the as-prepared samples are α-Fe2O3 microflowers, nanospindles, nanoparticles and nanorhombohedra. The magnetic properties and visible light photocatalytic properties of the products were investigated. The magnetic hysteresis measurements showed interesting magnetic property evolution among these α-Fe2O3 products, which can be attributed to their superstructure or the shape anisotropy. The photocatalytic measurements indicated that the α-Fe2O3 samples exhibit good photocatalytic property for Rhodamine B. [Copyright &y& Elsevier]

Abstract: Nanostructured CuO film was prepared using glass or stainless steel slices as substrate via a simple ammonia-assisted solution route at 60°C. The obtained CuO film was made up of well-crystallized nanosheets of 50–360nm in thickness and 0.7–4.5μm in width. The reaction time and the substrate have significant effects not only on the thickness, width, arrangement of the nanosheets but also on the morphology and the thickness of the films. The CuO film was characterized by SEM, TEM, XRD, IR, and Raman spectroscopy techniques. [Copyright &y& Elsevier]

Chitosan- N -2-hydroxypropyl trimethyl ammonium chloride (QTS) was prepared by reaction of chitosan (CS) and glycidyl trimethylammonium chloride. Later, O -acetyl-chitosan- N -2-hydroxypropyl trimethyl ammonium chloride (AQTS) was synthesized by reaction of QTS with acetic acid in the presence of SOCl 2 . Both derivatives were characterized by FTIR, 1 H NMR, TGA, and XRD techniques. The degree of quaternization of QTS was 85.5%, and the degree of acetyl (DA) of AQTS was from 1.63 to 2.31. Compared with CS, the solubility of QTS and AQTS was improved at different levels, especially AQTS, it could be dissolved in many organic solvents, water, and aqueous solution. Notably, the solubility of AQTS in organic solvents increased as DA increased, while the solubility in water was reversed. The results of CS, QTS, and AQTS against Escherichia coli and Staphylococcus aureus showed that QTS and AQTS exhibited higher antibacterial activity than CS, and the antibacterial activity of AQTS decreased with increased DA. Moreover, the inhibition effect was AQTS1 (DA 1.63) > AQTS2 (DA 2.02) > QTS > AQTS3 (DA 2.31). On the basis of the results of the present study, it could be emphasized that hydrophobicity and positive charge density might strongly affect the antibacterial activity of quaternary ammonium chitosan derivatives. [ABSTRACT FROM AUTHOR]