Navinchandra G. Shimpi

Synthesis and sensing applications of polyaniline nanocomposites: a review

A comprehensive review on the synthesis of PANI nanocomposites and their applications as gas sensors and biosensors has been presented. The multi-functionality of PANI nanocomposites have been extensively exploited in diverse applications with impressive results. The synergistic effects between the constituents have made these materials particularly attractive as sensing elements for gases and biological agents. Not only do PANI nanocomposites allow room temperature sensing of a large number of combustible or toxic gases and pollutants with high selectivity and sensitivity, they also enable immobilization of bioreceptors such as enzymes, antigen–antibodies, and nucleic acids onto their surfaces for detection of an array of biological agents through a combination of biochemical and electrochemical reactions. Efforts are on towards understanding the working mechanism of PANI nanocomposites which will increase their potential fields of applications.

Performance of hybrid nanostructured conductive cotton materials as wearable devices: an overview of materials, fabrication, properties and applications

Smart wearable devices can be fabricated using flexible and linear cable-type materials for applications in energy, electronics, sensing and healthcare products. Such wearable devices have been prepared by incorporating conductive nanostructures, metallic nanomaterials, hybrid nanocomposites and polymer nanocomposites on the surface of flexible and permeable cotton materials (threads, fibers, yarns and fabrics). In this paper, we present an overview of preparation methods of various conductive nanomaterials, hybrids and polymer nanocomposites and their embedment on cotton based flexible materials. The embedment of these functional hybrid nanostructures on the porous and permeable materials has provided the necessary potential for the development of wearable smart devices with improved characteristic properties. Moreover, the diversity of these characteristic properties and potential applications of functionalized cotton materials has been also discussed. This review paper will boost encouragement for the development of next generation smart and flexible devices which could be worn by human beings.

Performance of hybrid nanostructured conductive cotton threads as LPG sensor at ambient temperature: preparation and analysis

The present research work explores the feasibility of a novel sensor based on nanostructured cotton threads. These threads were functionalized using carbon nanotubes (CNTs) and PAni/γ-Fe2O3 nanostructures. To begin with, we prepared catalyst nanoparticles by a hydrothermal method. These nanofabricated catalyst particles were used to grow CNTs by a newly designed catalytic chemical vapor deposition set up. The resulting CNTs were subjected to strategic purification steps. Both nanofabricated catalyst and decontaminated CNTs were analysed to study their size, shape, surface morphology and crystalline structure. Pure CNTs were successfully incorporated on permeable cotton threads using basic submersion in a CNT-ink under an ultrasound environment. These profoundly conductive cotton threads were functionalized using PAni/γ-Fe2O3 nanostructures by facile ultrasound assisted in situ polymerization. The hybrid nanostructured cotton threads were prepared at different loadings of both CNTs and PAni/γ-Fe2O3 nanocomposite and their influence was further investigated to study their surface morphology, electrical behavior and sensing performance for the detection of LPG. A quick response time and maximum response value (Rres = 0.91) were observed for low concentration (50 ppm) detection of LPG at ambient temperature. So these hybrid nanostructured cotton based sensing threads could be easily woven into the textile materials which will be useful as wearable gadgets for LPG detection in household kitchens, manufacturing sites and industries. Also this work will boost an essential encouragement for the development of wearable smart sensing gadgets.

Microwave assisted one pot three component synthesis of propargylamine, tetra substituted propargylamine and pyrrolo[1,2-a]quinolines using CuNPs@ZnO–PTh as a heterogeneous catalyst

The present work deals with the investigation and catalytic activity analysis of copper nanoparticles (CuNPs) supported on a zinc oxide–polythiophene (ZnO–PTh) nanocomposite. CuNPs@ZnO–PTh was prepared using a simple impregnation method and characterized using various techniques (XRD, XPS, FT-IR, SEM, ICP-AES, TEM, TEM-EDS and EDAX). HR-TEM indicates that CuNPs supported on ZnO–PTh were of spherical shape and distributed uniformly over the nanocomposite with a particle size of ∼2–8 nm. Further, the synthesized CuNPs@ZnO–PTh was used as a heterogeneous catalyst for the synthesis of propargylamine, tetra substituted propargylamine (A3 and KA2 coupling reactions) and pyrrolo[1,2-a]quinoline (A3 coupling reactions) using a microwave technique in ethylene glycol as a recyclable, green and biodegradable solvent with 98% yield. The high catalytic activity of CuNPs@ZnO–PTh was due to the high surface area and synergetic effect of both the CuNPs and ZnO–PTh nanocomposite, which makes it cost effective and environmentally benign with high atom economy. Considering all above facts, this protocol was found to be more efficient and sustainable as compared to the available commercial methods.

Process Optimization for the Synthesis of Silver (AgNPs), Iron Oxide (α-Fe2O3NPs) and Core-Shell (Ag-Fe2O3CNPs) Nanoparticles Using the Aqueous Extract of Alstonia Scholaris: A Greener Approach

RESEARCH ARTICLE Process Optimization for the Synthesis of Silver (AgNPs), Iron Oxide (α-Fe2O3NPs) and Core-Shell (Ag-Fe2O3CNPs) Nanoparticles Using the Aqueous Extract of Alstonia Scholaris: A Greener Approach Navinchandra G. Shimpi, Mujahid Khan, Sharda Shirole and Shriram Sonawane Department of Chemistry, University of Mumbai, Sant Cruz (E) 400 098, India University Institute of Chemical Technology, North Maharashtra University, Jalgaon, India Department of Chemical Engineering Visvesvaraya National Institute of Technolog, Nagpur

Reusable zinc oxide nanoflowers for the synthesis of α-aminophosphonates under solvent-free ultrasonication

Abstract A simple wet chemical method is used to prepare zinc oxide nanoflowers (ZnO NFs) which were subjected to various characterization techniques such as XRD, FTIR, UV–Vis, FE-SEM, and XPS. XRD pattern indicates pure, crystalline, and monodispersed form with hexagonal wurtzite phase. The 3-D flower shape morphology with hexagonal ZnO nanorods was confirmed in FE-SEM. The synthesized ZnO NFs was used to study catalytic behavior in Kabachnik–Fields reaction under controlled ultrasound cavitation technique. High surface-to-volume ratio of ZnO NFs and the effect of ultrasonication enhances the yield of α-aminophosphonate. The catalyst was recycled and reused four times without any significant loss of its catalytic activity. Moreover, existing method becomes attractive and practical due to its easy, clean, fast, cost-effective, and eco-friendly procedure. Graphical Abstract

Green synthesis of zero valent colloidal nanosilver targeting A549 lung cancer cell: In vitro cytotoxicity

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