Facile Methodology Research Articles

Quantitative analysis of peel-off degree for printed electronics

We suggest a facile methodology of peel-off degree evaluation by image processing on printed electronics. The quantification of peeled and printed areas was performed using open source programs. To verify the accuracy of methods, we manually removed areas from the printed circuit that was measured, resulting in 96.3% accuracy. The sintered patterns showed a decreasing tendency in accordance with the increase in the energy density of an infrared lamp, and the peel-off degree increased. Thus, the comparison between both results was presented. Finally, the correlation between performance characteristics was determined by quantitative analysis.

Decorating biomass-derived porous carbon with Fe2O3 ultrathin film for high-performance supercapacitors

It is a challenge to make good use of biomass resources for energy storage applications. In this study, wheat straw, a common agricultural waste, is used as the precursor for synthesizing biomass-derived porous carbon (BPC), which is then decorated with Fe2O3 ultrathin film through a facile methodology. Benefiting from the hierarchical structure and synergetic effect, the BPC/Fe2O3 nanocomposite exhibits high performances for supercapacitors, i.e., large specific capacitance up to 987.9 F g−1 (219.5 mAh g−1) at a current density of 1 A g−1, great rate capability (423.8 F g−1 at 30 A g−1), and superior cyclability (82.6% capacitance retention after 3000 cycles). In addition, an aqueous asymmetric supercapacitor (ASC) is assembled with BPC/Fe2O3 as the anode material. The ASC delivers high specific energy of 96.7 Wh kg−1 and high specific power of 20.65 kW kg−1, making it one of the best performed ASC devices reported to date. The results of this study manifest great potential of constructing BPC/metal oxide heterostructures for efficient energy storage devices.

Facile and cost-effective methodology to fabricate MoS2 counter electrode for efficient dye-sensitized solar cells

Interests in the development of economical and high-efficiency counter electrodes (CEs) of dye-sensitized solar cell (DSSC) to replace the excessively cost and scarce platinum (Pt) CEs have been increased. In this report, we demonstrate a facile chemical bath deposition (CBD) route to prepare layered MoS2/fluorine-doped tin oxide (FTO) films that directly act as the CEs of DSSCs. A DSSC containing the CBD-synthesized MoS2/FTO CE (prepared at 0.03 M Mo source concentration, 90 °C bath temperature and 30 min deposition time) exhibits high power conversion efficiency (PCE) of 7.14%, which is approaching that of DSSC with Pt/FTO CE (8.73%). The electrocatalytic activity of the MoS2/FTO and Pt/FTO CEs are discussed in detail with their cyclic voltammetry (CV), Tafel polarization curves, and electrochemical impedance spectra (EIS). The observed results indicate that our low-cost CE has a high electrocatalytic activity for the reduction of triiodide to iodide and a low charge transfer resistance at the electrolyte–electrode interface with a comparable state to that of a Pt/FTO CE.

Enhanced self-assembly of block copolymers by surface modification of a guiding template

The formation of highly ordered patterns of block copolymers (BCPs) with high χ is important for next-generation lithography applications. We demonstrate here a surface-engineering methodology to enhance the self-assembly of poly(styrene-b-dimethylsiloxane) (PS-b-PDMS) BCPs with high χ by employing a hydroxyl-terminated polystyrene (PS-OH) brush. By precisely controlling the molecular weight (MW) and weight percent of PS-OH, well-ordered sub-20-nm BCP patterns were obtained over a large area in a short annealing time (<10 min) with the use of guiding templates. We systemically analyzed how the PS-OH brush affects the self-assembly kinetics of BCPs with various MWs and volume fractions. Moreover, the transmission electron microscopy (TEM) results strongly support that the PS-modulated surface plays an important role in the ordering of BCP patterns. We also achieved well-aligned 12 nm line and 18 nm dot patterns within 3 min by means of binary solvent vapor annealing at a moderate temperature under the optimum PS-OH brush conditions. These results provide a new platform for effective engineering and manipulation of the self-assembly of other BCPs for advanced BCP nanotechnologies. A facile and practical surface-engineering methodology to enhance the self-assembly of PS-b-PDMS BCPs with high χ by precisely controlling the molecular weight and weight percent of PS brushes. Highly ordered sub-20-nm BCP patterns were successfully obtained in a few minutes under the optimum PS brush condition.

Synthesis of microsize Fe/Cu bimetallic particles using in situ acid‐mediated coating: Application on decolorization of azo dye acid orange 7

Iron‐based bimetallic particle has become an attractive material in environmental remediation, particularly for wastewater treatment. However, it is yet to be applied in large scale processes, mainly due to the requirement of multistep syntheses for the desired materials, as well as the rigorous control of the conditions for its synthesis. This study introduces a facile methodology to synthesize micro‐size iron/copper bimetallic particles (mFe/Cu‐BPs) by in situ coating of Cu on the surface of Fe in an acidic media for the removal of azo dye Acid Orange 7 (AO7) in aqueous media. Morphological analyses showed that Cu planted on the surface of the particles exhibit a dense leaf‐like structure with great connectivity and electron movement between Fe0 core and Cu shell. In addition, the effects on the decolorization of AO7 via key parameters such as theoretical Cu mass loading (TMLCu), initial pH, dosage, and initial AO7 concentration were assessed. Experimental results revealed that the decolorization efficiency of AO7 was highly dependent on the operational conditions. Under optimal conditions (TMLCu of 0.6 g Cu/g Fe, initial pH of 3.0, mFe/Cu‐BP dosage of 45 g/L, and initial AO7 concentration of 1000 mg/L), decolorization of AO7 as a function of reaction time was investigated via UV‐vis spectrometry, which confirmed that the azo bond of AO7 successfully cleaved by mFe/Cu‐BPs. The maximum decolorization, COD, and TOC removal efficiencies were found to be 99.55, 83.91, and 73.81% after 30 min of reaction time, respectively. Lastly, the potential mechanism for the decolorization of AO7 is proposed. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1901–1907, 2018

Simultaneous determination of codeine and its co-formulated drugs acetaminophen and caffeine by utilising cerium oxide nanoparticles modified screen-printed electrodes

We report a facile and low-cost methodology for the simultaneous determination of codeine (COD) and its common co-formulated drugs acetaminophen (APAP) and caffeine (CAF) utilising cerium oxide nanoparticles modified screen-printed electrodes (CeO2-SPEs) for the first time. Interestingly, CeO2-SPEs offer a promising, sensitive, robust and chemically stable non-enzymatic electrochemical sensor for the simultaneous determination of APAP, COD and CAF without any interference / overlapping of voltammetric peaks/signals. The electro-analytical sensing of APAP, COD and CAF were explored using CeO2-SPEs over a wide concentration range with competitively low detection limits (3S/N) of 0.051, 0.043 and 2.4 μmol L−1 respectively. The CeO2-SPEs with nanoscale CeO2 architectures exhibit practical analytical utility for the accurate and simultaneous determination of APAP, COD and CAF in human serum samples with excellent recoveries. The results show exceptional electrochemical performance of CeO2-SPEs in term of simplicity, stability and sensing abilities that can effectively reduce processing costs for scalable production and routine analysis.

Ultrafast Nanoscale Polymer Coating on Porous 3D Structures Using Microwave Irradiation

AbstractThin polymer coatings are very popular, but the coatings on uneven surfaces or porous 3D structures are difficult to obtain with traditional methods. The pores are easily clogged due to nonuniform polymer curing processes caused by inevitable macroscale temperature gradients from their hotter outer to colder inner sides. Here an ultrafast and simple fabrication method is developed to obtain nanoscale coating layers on the inner and outer surfaces of a porous 3D sponge‐like carbon nanotube (CNT). Microwave irradiation rapidly and selectively heats the CNT immersed in a mixture solution of an uncured polymer and a diluent solvent, solidifying the polymer only adjacent to the CNT with five repeated 3 s microwave irradiation. The coating layers can be controlled by adjusting the concentration of the uncured polymer in the solution and controlling the CNT temperature via microwave power and irradiation time. The nanoscale coating strongly ties the junction between CNTs without filling the pores with the polymer, resulting in excellent resilience to compressive stress with large strains (≈180 kPa at 60%), which is maintained throughout repeated 8000 cycles of 0–60% strain. The unfilled pores allow for maintaining the low thermal conductivity, ≈26 mW m−1 K−1, and the electrical resistance is varied with strain. This facile selective polymer curing methodology can be utilized in processing various materials with uneven surfaces or pores.

Roll-to-Roll Production of Layer-Controlled Molybdenum Disulfide: A Platform for 2D Semiconductor-Based Industrial Applications.

A facile methodology for the large-scale production of layer-controlled MoS2 layers on an inexpensive substrate involving a simple coating of single source precursor with subsequent roll-to-roll-based thermal decomposition is developed. The resulting 50 cm long MoS2 layers synthesized on Ni foils possess excellent long-range uniformity and optimum stoichiometry. Moreover, this methodology is promising because it enables simple control of the number of MoS2 layers by simply adjusting the concentration of (NH4 )2 MoS4 . Additionally, the capability of the MoS2 for practical applications in electronic/optoelectronic devices and catalysts for hydrogen evolution reaction is verified. The MoS2 -based field effect transistors exhibit unipolar n-channel transistor behavior with electron mobility of 0.6 cm2 V-1 s-1 and an on-off ratio of ≈10³. The MoS2 -based visible-light photodetectors are fabricated in order to evaluate their photoelectrical properties, obtaining an 100% yield for active devices with significant photocurrents and extracted photoresponsivity of ≈22 mA W-1 . Moreover, the MoS2 layers on Ni foils exhibit applicable catalytic activity with observed overpotential of ≈165 mV and a Tafel slope of 133 mV dec-1 . Based on these results, it is envisaged that the cost-effective methodology will trigger actual industrial applications, as well as novel research related to 2D semiconductor-based multifaceted applications.

Convenient use of ortho-formylphenyl thioglycoside for regioselective conjugation with glycosyl acceptors towards regioselective 1,2-cis-glycosylation

GRAPHICAL ABSTRACT

Cu@Pd core-shell nanostructures for highly sensitive and selective amperometric analysis of histamine

We demonstrate a facile and rapid methodology for preparation of Cu@Pd core-shell nanostructures on a cost-effective pencil graphite substrate. Galvanic replacement reaction was carried out for palladium modification on template electrodeposited copper nanostructures on pencil graphite substrate. The nanostructures are shown to be very stable with excellent electrocatalytic activities. Under optimised conditions, they could be used for histamine sensing at a very low oxidation potential of +0.55V vs. Ag/AgCl. The low oxidation potential enabled sensitive and selective analysis of histamine using chronoamperometry without any interference from oxygen evolution reactions. We have demonstrated that the sensor shows excellent selectivity towards histamine even in the presence of many of the common interfering biogenic amines. The sensor exhibited a sensitivity of 0.082 μ A/μ M/cm 2 with a limit of detection as low as 3.2 ± 0.1nM. The oxidation potential and limit of detection obtained using this sensor are much superior to the results reported so far in the literature. Practical feasibility of the developed sensor was manifested by histamine analysis in canned tuna fish samples, where the chronoamperometric estimation was also validated by conventional HPLC analysis.

One-Pot Facile Methodology to Synthesize Chitosan-ZnO-Graphene Oxide Hybrid Composites for Better Dye Adsorption and Antibacterial Activity.

Novel chitosan–ZnO–graphene oxide hybrid composites were prepared using a one-pot chemical strategy, and their dye adsorption characteristics and antibacterial activity were demonstrated. The prepared chitosan and the hybrids such as chitosan–ZnO and chitosan–ZnO–graphene oxide were characterized by UV-Vis absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. The thermal and mechanical properties indicate a significant improvement over chitosan in the hybrid composites. Dye adsorption experiments were carried out using methylene blue and chromium complex as model pollutants with the function of dye concentration. The antibacterial properties of chitosan and the hybrids were tested against Gram-positive and Gram-negative bacterial species, which revealed minimum inhibitory concentrations (MICs) of 0.1 µg/mL.

Improved performance of inkjet-printed Ag source/drain electrodes for organic thin-film transistors by overcoming the coffee ring effects

Inkjet printing is a promising technology for the scalable fabrication of organic electronics because of the material conservation and facile patterning as compared with other solution processing techniques. In this study, we have systematically investigated the cross-sectional profile control of silver (Ag) electrode via inkjet printing. A facile methodology for achieving inkjet-printed Ag source/drain with improved profiles is developed. It is demonstrated that the printing conditions such as substrate temperature, drop spacing and printing layers affect the magnitude of the droplet deposition and the rate of evaporation, which can be optimized to greatly reduce the coffee ring effects for improving the inkjet-printed electrode profiles. Ag source/drain electrodes with uniform profiles were successfully inkjet-printed and incorporated into organic thin-film transistors (OTFTs). The resulting devices showed superior electrical performance than those without special treatments. It is noted to mention that the strategy for modulating the inkjet-printed Ag electrodes in this work does not demand the ink formulation or complicated steps, which is beneficial for scaling up the printing techniques for potential large-area/mass manufacturing.

Organic Solvent-Free Fabrication of Durable and Multifunctional Superhydrophobic Paper from Waterborne Fluorinated Cellulose Nanofiber Building Blocks.

In view of a great demand for paper-based technologies, nonwettable fibrous substrates with excellent durability have drawn much attention in recent years. In this context, the use of cellulose nanofibers (CNFs), the smallest unit of cellulosic substrates (5-20 nm wide and 500 nm to several microns in length), to design waterproof paper can be an economical and smart approach. In this study, an eco-friendly and facile methodology to develop a multifunctional waterproof paper via the fabrication of fluoroalkyl functionalized CNFs in the aqueous medium is presented. This strategy avoids the need for organic solvents, thereby minimizing cost as well as reducing safety and environmental concerns. Besides, it widens the applicability of such materials as nanocellulose-based aqueous coatings on hard and soft substrates including paper, in large areas. Water droplets showed a contact angle of 160° (±2°) over these surfaces and rolled off easily. While native CNFs are extremely hydrophilic and can be dispersed in water easily, these waterborne fluorinated CNFs allow the fabrication of a superhydrophobic film that does not redisperse upon submersion in water. Incorporated chemical functionalities provide excellent durability toward mechanochemical damages of relevance to daily use such as knife scratch, sand abrasion, spillage of organic solvents, etc. Mechanical flexibility of the chemically modified CNF composed paper remains intact despite its enhanced mechanical strength, without additives. Superhydrophobicity induced excellent microbial resistance of the waterproof paper which expands its utility in various paper-based technologies. This includes waterproof electronics, currency, books, etc., where the integrity of the fibers, as demonstrated here, is a much-needed criterion.

Rapid Sonochemical Approach Produces Functionalized Fe3O4Nanoparticles with Excellent Magnetic, Colloidal, and Relaxivity Properties for MRI Application

Functionalized Fe3O4 nanoparticles (NPs) have emerged as a promising contrast agent for magnetic resonance imaging (MRI). Their synthesis and functionalization methodology strongly affect their performance in vivo. The methodology most used in the literature for the synthesis of Fe3O4 NPs is thermal decomposition, which has proven to be time-consuming, expensive, and laborious, as it requires further ligand exchange strategies to transfer the as-synthesized nanoparticles from organic to aqueous solvents. This work describes a rapid and facile sonochemical methodology to synthesize and functionalize Fe3O4 NPs with excellent physicochemical properties for MRI. This sonochemistry approach was used to produce, in 12 min, Fe3O4 NPs functionalized with polysodium acrylate (PAANa), trisodium citrate (CIT), branched polyethylenimine (BPEI), and sodium oleate. X-ray diffraction and transmission electron microscopy demonstrated that the NPs were composed of a single inverse spinel phase with an average diameter of ...

In situ one step synthesis of Fe inserted octaethylporphyrin/polyindole: A multifunctional hybrid material with improved electrochemical and electrical properties

We report a facile and novel methodology for synthesis of Fe(II)-octaethylporphyrin/polyindole (Fe-OEP/PIn) hybrid material for electronic and electrochemical applications. The novelty of the work lies in coordination of iron in the OEP cavity and polymerization of indole monomer in a single step at room temperature. The ferric chloride used as oxidizing agent for polymerization of indole and the reduced Fe(II) ions are allowed to occupy the OEP cavity due to strong attraction of Fe(II) state towards porphyrinic cavity. The as synthesised hybrid materials are characterized and further used for fabrication of Schottky diode using a sandwiched structure Al/Fe-OEP-PIn/ITO which shows 0.21 cm2/Vs mobility, 2.1 ideality factor, and 0.60 eV barrier height. The improvement in electrochemical and electronic properties is discussed taking into account of outcome of various characterizations. Our study demonstrates the facile and novel synthesis of Fe-OEP/PIn hybrid material and its electrochemical and organic device applications.

Structural, morphological and magnetic properties of Sr0.3La0.48Ca0.25n[Fe(2−0.4/n)O3]Co0.4 (n = 5.5, 5.6,5.7,5.8, 5.9, 6.0) hexaferrites prepared by facile ceramic route methodology

In present work, M-type strontium hexaferrite with chemical composition of Sr0.3La0.48Ca0.25n[Fe(2−0.4/n)O3]Co0.4 (n = 5.5, 5.6, 5.7, 5.8, 5.9, 6.0) magnetic powder were synthesized by using facile ceramic route methodology. The structural, morphological and magnetic properties of the products were investigated by using X-rays diffraction (XRD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM) techniques, respectively. There is a single magnetoplumbite phase in the magnetic powders containing (5.5 ≤ n ≤5.8) and (n ≥ 5.9) magnetic some impurities begin to seem in the structure. The magnets have shaped hexagonal structures. Magnetic properties of the samples were metric by permanent magnetic measuring equipment Vibrating Sample Magnetometer, respectively. We report our investigation of n-aggregation iron content on crystalline size characterization and magnetic properties of the specimen. It is originate that the desirable quantity of n-aggregation iron content substitution may curiously increase saturation magnetization (Ms) and intrinsic coercivity (Hc). With the iron addition for the same sintering temperature at 1260 °C, (Ms) and (Hc) first increase and then decrease gradually.

Molecular Hybridization‐Guided Construction of Convolutamydine A‐fused β‐Ionone Scaffolds and their Biological Evaluation for Anticancer Activities

Described herein is a facile and efficient methodology toward the synthesis of novel convolutamydine A‐incorporated β‐ionone scaffold 3 from an Aldol addition event of β‐ionone to isatins via enamine Et2NH catalysis. Products featuring a quaternary carbon center were smoothly obtained in good yields (up to 96% yield). This protocol also represents the first construction of ionone skeleton‐fused oxindole molecules, thus leading to new knowledge in the fields of both molecular complexity and diversity‐oriented synthesis and the lead compound discovery. Furthermore, their biological activities against human leukemia cells K562 have been preliminarily demonstrated by in vitro assays. The results demonstrated that most of these compounds obtained by this protocol showed comparable with or even much better than the positive control of Cisplatin.

Facile One-Pot Synthesis Methodology for Nitrogen-Containing Heterocyclic Derivatives of 3,5-Disubstituted 4,5-Dihydro-1H-Pyrazole, Their Biological Evaluation and Molecular Docking Studies

A series of 2-pyrazoline derivatives (PS-1 to PS-16) were synthesized by reacting different aromatic/heteroaromatic aldehydes and ketones, in a two-step reaction through Claisen – Schmidt condensation, followed by cyclization of the resulting chalcones with hydrazine hydrate in the presence of a base using conventional and microwave approaches. The synthesized derivatives were characterized by various physicochemical methods including IR, 1H-NMR, 13C-NMR, and mass spectroscopic data and elemental analysis. The antidepressant and anti-anxiety activities were evaluated using suitable animal models. Compounds PS-3, and PS-14 showed noticeable antidepressant activity, by reducing the duration of immobility in both tests, while compounds PS-9 and PS-12 were found to possess good anxiolytic activity (by increasing the number of arm entries and open arm exploratory time) at the tested doses (50 and 100 mg/kg b.w.) in comparison to standard drugs imipramine and diazepam, respectively. In order to elucidate binding interactions of the synthesized derivatives to the MAO-A target protein, molecular docking was employed which demonstrated the key interactions with amino acid residues Phe208, Asn181, and Tyr407 at the binding site. Further, the ADME properties of the synthesized derivatives were predicted and found to fall within the stated limits.

Hydrothermally derived zinc sulfide sphere-decorated titanium dioxide flower-like composites and their enhanced ethanol gas-sensing performance

Zinc sulfide (ZnS) sphere-decorated titanium dioxide (TiO2) flowers at various ZnS hydrothermal synthesis durations were synthesized using a two-step facile hydrothermal methodology. The ZnS hydrothermal synthesis duration affected the content and distribution of ZnS spheres decorated on the surfaces of TiO2 petals. Thus, the separate and random distribution of these spheres, without considerable aggregation, could be obtained by adequately controlling the ZnS hydrothermal synthesis duration. A structural analysis demonstrated that the as-synthesized ZnS spheres and TiO2 flowers were in crystalline cubic zinc blend and rutile phases, respectively. Moreover, the gas-sensing response of the TiO2 flowers to ethanol vapor markedly enhanced after the decoration of the ZnS spheres. An optimal ZnS hydrothermal synthesis duration of 2 h for the TiO2–ZnS composites was determined to result in the highest gas-sensing response at the given gas-sensing test condition. The strongly favorable ion–species interactions in the gas sensing of ZnS spheres and the formation of TiO2/ZnS heterojunctions in the TiO2–ZnS composites accounted for the enhanced gas-sensing responses of TiO2 flowers decorated with ZnS spheres in this study.

Electrostatically Assembled Magnetite Nanoparticles/Graphene Foam as a Binder-Free Anode for Lithium Ion Battery.

Lithium ion batteries (LIBs) are promising candidates for energy storage, with the development of novel anode materials. We report the fabrication of Fe3O4 nanoparticles/graphene foam via electrostatic assembly and directly utilize it as a binder-free anode for LIBs. Owing to the integrated effect of the well-dispersed Fe3O4 nanoparticles and the conductive graphene foam network, such composite exhibited remarkable electrochemical performances. It delivered a large reversible specific capacity reaching to ∼1198 mAh g-1 at a current density of 100 mA g-1, a good rate capacity, and an excellent cyclic stability over 400 cycles. This work demonstrated a facile methodology to design and construct high-performance anode materials for LIBs.