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This work describes a simple, inexpensive, and robust method to prepare a flexible "all in one" integrated hydrogel supercapacitors (HySCs). Preparing smart hydrogels with high electrical conductivity, ability to stretch significantly, and excellent mechanical properties is the last challenge for tailored wearable devices. In this paper, we employed a physical crosslinking process that involves consecutive freezing and thawing cycles to prepare a polyvinyl alcohol (PVA)-based hydrogel. Exploiting the self-healing properties of these materials, the assembly of the different layers of the HySCs has been performed. The ionic conductivity within the electrolyte layer arises from the inclusion of an H2SO4 solution in the hydrogel network. Instead, the electronic conductivity is facilitated by the addition of the conductive polymer PANI-PAMPSA into the hydrogel layers. Electrochemical measures have highlighted newsworthy properties related to our HySCs, opening their use in wearable electronic applications. [ABSTRACT FROM AUTHOR]

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Metal–organic frameworks (MOFs) are a class of crystalline porous materials with outstanding physical and chemical properties that make them suitable candidates in many fields, such as catalysis, sensing, energy production, and drug delivery. By combining MOFs with polymeric substrates, advanced functional materials are devised with excellent potential for biomedical applications. In this research, Zeolitic Imidazolate Framework 8 (ZIF-8), a zinc-based MOF, was selected together with cellulose, an almost inexhaustible polymeric raw material produced by nature, to prepare cellulose/ZIF-8 composite flat sheets via an in-situ growing single-step method in aqueous media. The composite materials were characterized by several techniques (IR, XRD, SEM, TGA, ICP, and BET) and their antibacterial activity as well as their biocompatibility in a mammalian model system were investigated. The cellulose/ZIF-8 samples remarkably inhibited the growth of Gram-positive and Gram-negative reference strains, and, notably, they proved to be effective against clinical isolates of Staphylococcus epidermidis and Pseudomonas aeruginosa presenting different antibiotic resistance profiles. As these pathogens are of primary importance in skin diseases and in the delayed healing of wounds, and the cellulose/ZIF-8 composites met the requirements of biological safety, the herein materials reveal a great potential for use as gauze pads in the management of wound infections. [ABSTRACT FROM AUTHOR]

A copper-containing metal organic framework was prepared using the new organic linker 5-(2-{[(prop-2-yn-1-yloxy)carbonyl]-amino}ethoxy)isophthalic acid [1,3-H2YBDC (where Y = alkYne and BDC = Benzene DiCarboxylate)] and functionalized with gold particles by reaction with HAuCl4 under thermal treatment in methanol. The resulting system was investigated by complementary techniques to obtain information on its structure and morphology. In the present work, x-ray photoelectron spectroscopy (XPS) was employed to analyze the chemical composition of a representative specimen. Besides wide scan spectra, data obtained by the analysis of the C 1s, O 1s, N 1s, Cu 2p, and Au 4f signals are presented and critically discussed. The results highlight the reduction of Au(III) to mostly Au(I) species. Overall, the data presented herein may act as useful guidelines for the eventual tailoring of material properties and their possible implementation toward functional applications in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

The development of green, low cost and sustainable synthetic routes to produce metal nanoparticles is of outmost importance, as these materials fulfill large scale applications in a number of different areas. Herein, snail slime extracted from Helix Aspersa snails was successfully employed both as bio-reducing agent of silver nitrate and as bio-stabilizer of the obtained nanoparticles. Several trials were carried out by varying temperature, the volume of snail slime and the silver nitrate concentration to find the best biogenic pathway to produce silver nanoparticles. The best results were obtained when the synthesis was performed at room temperature and neutral pH. UV–Visible Spectroscopy, SEM-TEM and FTIR were used for a detailed characterization of the nanoparticles. The obtained nanoparticles are spherical, with mean diameters measured from TEM images ranging from 15 to 30 nm and stable over time. The role of proteins and glycoproteins in the biogenic production of silver nanoparticles was elucidated. Infrared spectra clearly showed the presence of proteins all around the silver core. The macromolecular shell is also responsible of the effectiveness of the synthesized AgNPs to inhibit Gram positive and Gram negative bacterial growth. [ABSTRACT FROM AUTHOR]

Ultrathin-film composite membranes wereintroduced in a general approach for designing chemical sensors. A prototype electrochemical glucose sensor was prepared and evaluated to demonstrate the feasibility of this new approach for sensor design. Fast response time, simplicity of construction and applicability to a number of molecular recognition chemistries and signal transduction schemes were validated as the potential advantages of the sensor.

The studies of the synthesis, characterization, and evaluation of the main structural and electronic properties of new mono- and dinuclear complexes in which aromatic 5-substituted tetrazolates such as [4-TBN](super -) and [BTB](super 2-) are coordinated to one or two Ru(tpy)(bpy) units are reported. This highlights rather good luminescence efficiency and a poor bridge-mediated electronic communication between the metal centers of the dinuclear complexes.

Indium tin oxide (ITO) substrates were functionalized with fluoroalkylsilanes (FAS) having formula R F C(O)N(R)(CH 2 ) 3 Si(OMe) 3 ( 1 , R = H, R F  = C 5 F 11 ; 2 , R = CH 3 , R F  = C 5 F 11; 3 , R = H, R F  = C 3 F 7 ) and containing embedded amide moieties between the perfluoroalkyl chain and the syloxanic moiety. Subsequently, Au nanoparticle deposition (AuNP) onto the ITO-FAS functionalized surfaces was carried out by immersion into a solution of citrate-stabilized AuNP. The ITO-FAS and AuNP/ITO-FAS modified systems were characterized by various complementary techniques and compared with AuNP/ITO modified with R F (CH 2 ) 2 Si(OEt) 3 ( 4 , R F  = C 6 F 13 ), free from functional groups between the fluorinated tail and the syloxanic moiety. The results showed that only ITO glasses modified with 1 , 2 and 3 displayed an oleophobic, as well as hydrophobic, behaviour and that the AuNP Surface Coverage (SC %) directly depended on the fluoroalkylsilane nature with the following trend: 60% ITO-2  > 16% ITO-3  > 9% ITO-1  > 3% ITO-4 . The obtained results revealed that, in organosilane 2 , the presence of a methyl group on the amide nitrogen increases the steric hindrance in the rotation around the N CO bond, resulting in the co-presence of two stable conformers in comparable amounts. Their co-presence in solution, combined with the lack of intermolecular N H⋯OC N hydrogen bonds among the anchored molecules, has dramatic influences on the functionalized ITO, yielding a disorderedly packed coating able to accommodate a large quantity of AuNP. These results indicate that AuNP can act as excellent probes to evaluate the coating layer quality but, at the same time, it is possible to tune the gold loading on electroactive surfaces depending on the chemical structure of the used fluorinated silane. [ABSTRACT FROM AUTHOR]

The synthesis and properties of three copolymers obtained through a Knoevenagel polycondensation are reported. They are soluble in organic solvents, filmable, and solvatochromic. They are characterized through gel permeation chromatography, NMR and UV-vis spectroscopies, cyclic voltammetry, and atomic force microscopy. They display some proneness to form p-stacks, broad absorptions up to about 700 nm, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies that fit those of [6,6]-phenyl-C61-butyric acid methyl ester ([60]PCBM). The polymers are incorporated in blends with PCBM within bulk heterojunction devices. The best results are found for polymer solar cells obtained from P1 (2.7% power conversion efficiency). The insertion of alkylsulfanyl chains improves the photovoltaic performances, with respect to those of alkyl-substituted analogous polymers. The Jsc of the devices are greatly enhanced, supporting the employment of (alkylsulfanyl)thienyl units as base units in photoactive materials. [ABSTRACT FROM AUTHOR]

Self-supporting membranes built entirely of carbon nanotubes have been prepared by wet methods and characterized by Raman spectroscopy. The membranes are used as supports for the electrodeposition of Pt nanoparticles without the use of additional additives and/or stabilizers. The Pt precursor is an ad hoc synthesized ammonium-ethylimidazolium chloroplatinate(IV) salt, [NH3(CH2)2MIM)][PtCl6]. The Pt complex was characterized using NMR spectroscopy, XRD, ESI-MS, and FTIR spectroscopy. The interaction between the Pt-carbon nanotubes nanocomposites and hydrogen is analyzed using electrochemical and quartz microbalance measurements under near-ambient conditions. The contribution of the Pt phase to the hydrogen adsorption on nanotube is found and explained by a kinetic model that takes into account a spillover event. Such a phenomenon may be exploited conveniently for catalysis and electrocatalysis applications in which the hybrid systems could act as a hydrogen transfer agent in specific hydrogenation reactions. [ABSTRACT FROM AUTHOR]

Metal/organosilane/oxide sandwich structures were prepared via a two-step self-assembly method. First, indium tin oxide (ITO) substrates were functionalized with the following fluoroalkylsilanes (FAS): R F C(O)N(H)(CH 2 ) 3 Si(OMe) 3 ( 1 , R F = C 5 F 11 ), containing an embedded amide between the perfluoroalkyl chain and the syloxanic moiety, and R F (CH 2 ) 2 Si(OEt) 3 ( 2 , R F = C 6 F 13 ). Subsequently, Au nanoparticles (Au NPs ) introduction in the obtained systems was carried out by controlled immersion into a solution of citrate-stabilized Au NPs . The physico-chemical properties of the target materials were thoroughly investigated by using various complementary techniques. Finally, the application of such systems as catalysts for methanol electro-oxidation under alkaline conditions was investigated, revealing the synergistical role played by FAS and Au NPs in promoting a remarkable electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Raman and IR spectroscopy were used to investigate the changes induced in yak hair keratin by the straightening treatment based on glyoxylic acid. The amino acidic residues that appeared involved in the reaction with glyoxylic acid were serine and lysine; the involvement of the latter was deduced by the spectroscopic detection of iminic species, resulting from the reaction between the aminic group of lysine and the carbonyl group of glyoxylic acid. The reaction with glyoxylic acid induced conformational rearrangements that mainly involved the fibre bulk rather than the cuticle. Changes in the average tyrosine environment and its hydrogen-bonding state were detected: at increasing glyoxylic acid incorporation, the tyrosine residues appeared more exposed, probably because of H-bond interactions with the COOH group. The distribution of the disulfide bridge conformation was also affected, although no cleavage of the S-S bond was detected, in agreement with the shiny and healthy appearance of the fibres. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This work describes a new one-step method for the preparationofAuNP/LDH nanocomposites via the polyol route. The novelty of thisfacile, simple synthesis is the absence of additional reactants suchas reductive agents or stabilizer, which gives the possibility toobtain phase-pure systems free of undesiderable effect. The AuNP formationis confirmed by SEM, TEM, PXRD, and XAS; moreover, the electrochemicalcharacterization is also reported. The electrocatalytic behavior ofAuNP/LDH nanocomposites has been investigated with respect to theoxidation of methanol in basic media and compared with that of pristineNiAl-Ac. The 4-fold highest catalytic efficiency observed with AuNP/LDHnanocomposites suggests the presence of a synergic effect betweenNi and AuNP sites. The combination of these experimental findingswith the low-cost synthesis procedure paves the way for the exploitationof the presented nanocomposites materials as catalysts for methanolfuel cells. [ABSTRACT FROM AUTHOR]

Abstract: A polymeric membrane-based ion-selective electrode (ISE) for the determination of l-ascorbic acid (l-AA) was developed. The sensor was fabricated by modifying glassy carbon electrodes with molecularly imprinted polypyrrole (PPy) synthesized by electropolymerization of the monomer in the presence of ascorbate. A comparison between the non-imprinted modified electrode (PPy-NIP) and the molecularly imprinted polymer (PPy-MIP) is reported. The molecularly imprinted polymer improves the performances of the sensor, especially if the PPy film has been submitted to an oxidation treatment. The PPy-MIPox electrode shows near-Nernstian response (approx. −57mV/decade) to the ascorbate over the concentration range between 5×10−6 M and 2×10−3 M and it can be used for more than 3 weeks without any considerable change in the measured response. The potentiometric sensor has been successfully applied to the determination of ascorbate in food and pharmaceutical samples (recoveries of about 100%). [Copyright &y& Elsevier]

Abstract: In this work the novel, robust, air- and moisture-stable gold(III)-aminoethyl imidazolium aurate salt [Cl3AuNH2(CH2)2ImMe][AuCl4] (1) has been employed as precursor for the electrosynthesis of gold nanoparticles (AuNPs) onto ITO electrodes in 0.5moldm−3 H2SO4 aqueous solution without the use of additional additives and/or stabilizers. The electrode termed ILNH2-AuNPs200 prepared at a fixed electrodeposition time (t d) of 200s was characterized with AFM, SEM, XRD diffraction as well as cyclic voltammetry (CVs) and compared with an electrode in which the AuNPs have been electrodeposited from KAuCl4 in the presence of KI as additive at the same t d (AuNPs200). The effect of the t d (i.e. 50s or 500s; electrodes ILNH2-AuNPs50 and ILNH2-AuNPs500, respectively) was also investigated together with the electrocatalytic activity towards methanol oxidation in alkaline medium of all the prepared electrodes. The comparison with AuNPs obtained with KI as additive shows that the presence of the amino-functionalized imidazolium moiety although not relevant in relation to the particle size, favours the metal electrodeposition process and plays an important role in the enhancement of the following parameters: (i) surface coverage (S.C.), (ii) electroactive particle coverage Φ p %, (iii) electroactive surface area σ red(exp)/σ red(theor) and (iv) catalytic efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Electrochemical polymerization of thiophene oligomers (n =4) bearing an hexamethylenic ω-methoxy functionalized side chain at the 3-3″′ position of the thiophene rings, was performed in different solvents and electrode surfaces. The degree of polymerization and the electrochemical behaviour of the different electrosynthetized polymers were compared with a polymer obtained by a chemical method. The polymeric films were characterized using cyclic voltammetry, FT-IR, AFM and SEM microscopy. [Copyright &y& Elsevier]

Abstract: A novel series of functionalized polythiophenes incorporating 3-(ω-bromoalkyl) pendants are synthesized by electrochemical polymerization. The effect of the solvent on the electrosynthesis is investigated. The polymeric films are characterized using cyclic voltammetry, FT-IR, AFM and SEM microscopy. The poly[3-(6-bromohexyl)thiophene] film cast on GC or ITO electrode surface is compared with a sample obtained by a chemical method. [Copyright &y& Elsevier]

This paper investigates the electrochemical properties of a new Cu(II)-based metal-organic framework (MOF). Noted as Cu-YBDC, it is built upon a linker containing the propargyl carbamate functionality and immobilized on a glassy carbon electrode by drop-casting (GC/Cu-YBDC). Afterward, GC/Cu-YBDC was treated with HAuCl4 and the direct electro-deposition of Au nanoparticles was carried at 0.05 V for 600 s (GC/Au/Cu-YBDC). The performance of both electrodes towards nitrite oxidation was tested and it was found that GC/Au/Cu-YBDC exhibited a better electrocatalytic behavior toward the oxidation of nitrite than GC/Cu-YBDC with enhanced catalytic currents and a reduced nitrite overpotential from 1.20 to 0.90 V. Additionally GC/Au/Cu-YBDC showed a low limit of detection (5.0 μM), an ultrafast response time (<2 s), and a wide linear range of up to 8 mM in neutral pH. [ABSTRACT FROM AUTHOR]

Abstract: A thin compact layer of TiO2 deposited on the conductive transparent substrate of a dye-sensitized solar cell photoanode, (blocking layer, BL) can enhance the performances of the entire device. In this paper, an optimized spin coating process using an alcoholic TiCl4 solution was developed and correlated to the final properties of the layer. The physicochemical characteristics of the precursor solution and the spin coating parameters were optimised to obtain a uniform layer. XRD, FE-SEM, UV–Vis spectroscopy, AFM, cyclic voltammetry and electrochemical impedance spectroscopy were used to evaluate the influence of the number of deposition cycles on the TiO2 layer. The results were compared with those obtained using a conventional dip coating technique, showing that the newly developed spin coating process produces blocking layers with superior properties. Finally, analyses of the photovoltaic performances of the complete cell confirmed that an optimized blocking layer can lead to an improvement of the solar conversion efficiency of about 84%. [Copyright &y& Elsevier]

In the past decade, hydrogels have attracted growing interest for emerging applications in flexible electronic devices, human-machine interactions, energy supply, or energy storage. Developing a multifunctional gel architecture with superior ionic conductivity and good mechanical flexibility is a bottleneck to overcome. Herein, poly(vinyl alcohol)/sulfuric acid (PVA-H 2 SO 4 ) hydrogels were prepared via a freeze-thaw method. With the aim of tuning the formulation in view of a possible application in energy storage, the effects of different combinations in terms of the molecular weight (MW) of PVA and PVA-H 2 SO 4 weight ratio were investigated. Moreover, exploiting the self-healing properties of these hydrogels and the easy possibility of functionalizing them, i.e., introducing a conducting polymer such as poly(2-acrylamido-2-methyl-1-propane) sulfonic acid doped polyaniline (PANI&#95;PAMPSA), a sandwiched all-in-one double-layer hydrogel (electrode/electrolyte configuration) was prepared (PVA-H 2 SO 4 -PANI&#95;PAMPSA/PVA-H 2 SO 4 ). Results showed that the water content is independent of the PVA amount and MW; the polymer concentration has a significant effect on the formation of crystalline domains and therefore on swelling degree, whereas the cross-linking degree depends on the MW. The PVA MW has the maximum effect on the swelling percentage normalized with respect to the polymer fraction and the tensile properties of the hydrogel. The assembled all-in-one electrode/electrolyte shows promising ionic conductivity (439.7 mS cm -1 ) and specific capacitance performance (0.297 mF cm -2 at a current density of 0.025 mA cm -2 ), as well as excellent flexibility and considerable self-healing properties. These results will promote the development of self-healing symmetrical supercapacitors for storage devices in wearable electronics., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The well-known ability to selectively drive nanomagnetic materials coated with anticancer drugs into tumor cells suggested the synthesis and the characterization of magnetic nanoparticles (MNPs) functionalized with ( R )-9-acetoxystearic acid, the acetic ester of ( R )-9-hydroxystearic acid (9-HSA), an antiproliferative agent active against different cancer cells. The acyl chloride of ( R )-9-acetoxystearic acid, synthesized in two steps from 9-HSA, was reacted with (3-aminopropyl)triethoxysilane, chosen as a linker between MNPs and the stearyl moiety. In the last step, the novel amide was bound to magnetite NPs by reaction with silyl groups. A detailed structural, chemical, and magnetic characterization of the obtained material proved that it possesses properties in agreement with the requirements for drug delivery, opening the possibility to further insights focused on the 9-HSA biomedical applications., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

The fabrication of silane-based fluorinated self-assembled monolayers (FSAMs) on indium tin oxide (ITO, a transparent electrode) was carried out making use of the following fluoroalkylsilanes (FAS): 2,2,3,3,4,4,5,5,6,6,6-undecafluoro-N-[3-(trimethoxysilyl)propyl]hexanamide (1; R(F) = C5F11) and 1,1,2,2,3,3,4,4,4-nonafluoro-N-[3-(trimethoxysilyl)propyl]butane-1-sulfonamide (2; R(F) = C4F9), containing an embedded amide and a sulfonamide group, respectively, between the short perfluoroalkyl chain (R(F) with C < 6) and the syloxanic moiety. The obtained FSAM-modified/ITO systems were characterized by X-ray photoelectron spectroscopy (XPS), contact angle (CA), surface energy measurements, and electrochemical impedance spectroscopy (EIS) and compared to ITO modified with a 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane (3; R(F) = C6F13), with the perfluoroalkyl group linked to the syloxanic moiety through a simple hydrocarbon chain. The results obtained show that the presence of the -NHCO- and -NHSO2- groups have a different mode of action and, with the former, despite the short perfluoroalkyl chain, the ITO-1 system presents a CA (Θ(water )= 113.5°) and surface energy (γl = 14.0 mJ m(-2)) typical of amphiphobic materials. These properties can be exploited in a variety of applications, such as self-cleaning, anti-fouling, and anti-fingerprint coatings, and in advanced microelectronic components.