Indian Institute of Technology Ropar

About: Indian Institute of Technology Ropar is a education organization based out in Ropar, India. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 1014 authors who have published 2878 publications receiving 35715 citations.

A novel zinc(II) and hydrogen sulphate selective fluorescent “turn-on” chemosensor based on isonicotiamide: INHIBIT type's logic gate and application in cancer cell imaging

Abstract: We have developed a novel isonicotiamide-based fluorescent “turn-on” chemosensor 1 for the selective detection of Zn2+ and HSO4−. The sensor 1 can detect Zn2+ and HSO4− with a detection limit down to the nanomolar level by forming a complex in 1 : 1 stoichiometry in the presence of other anions and 2 : 1 in presence of cations in aqueous solution. Density functional theory calculations on 1 and the 1-Zn2+/HSO4− complexes are consistent with the experimental results. We have successfully utilized the above cation and anion for the fabrication of INHIBIT molecular logic gates. Furthermore the receptor 1 successfully detected the Zn2+ and HSO4− ions in HeLa cells cultured in Zn2+ and HSO4− enriched medium.

Lewis Acid Catalyzed Annulation of Cyclopropane Carbaldehydes and Aryl Hydrazines: Construction of Tetrahydropyridazines and Application Toward a One-Pot Synthesis of Hexahydropyrrolo[1,2-b]pyridazines

Abstract: In this report, a facile synthesis of tetrahydropyridazines via a Lewis acid catalyzed annulation reaction of cyclopropane carbaldehydes and aryl hydrazines has been demonstrated. Moreover, the generated tetrahydropyridazine further participated in a cycloaddition reaction with donor–acceptor cyclopropanes to furnish hexahydropyrrolo[1,2-b]pyridazines. We also performed these two steps in one pot in a consecutive manner. In addition, a monodecarboxylation reaction of hexahydropyrrolo[1,2-b]pyridazine was achieved with a good yield.

Bilayer graphene/HgCdTe based very long infrared photodetector with superior external quantum efficiency, responsivity, and detectivity

Abstract: We present a high-performance bilayer graphene (BLG) and mercury cadmium telluride (Hg1−xCdx=0.1867Te) heterojunction based very long wavelength infrared (VLWIR) conductive photodetector. The unique absorption properties of graphene enable a long carrier lifetime of charge carriers contributing to the carrier-multiplication due to impact ionization and, hence, large photocurrent and high quantum efficiency. The proposed p+-BLG/n-Hg0.8133Cd0.1867Te photodetector is characterized and analyzed in terms of different electrical and optical characteristic parameters using computer simulations. The obtained results are further validated by developing an analytical model based on drift-diffusion, tunneling and Chu's methods. The photodetector has demonstrated a superior performance including improved dark current density (∼1.75 × 10−14 µA cm−2), photocurrent density (∼8.33 µA cm−2), internal quantum efficiency (QEint ∼ 99.49%), external quantum efficiency (QEext ∼ 89%), internal photocurrent responsivity (∼13.26 A W−1), external photocurrent responsivity (∼9.1 A W−1), noise equivalent power (∼8.3 × 10−18 W), total noise current (∼1.06 fA), signal to noise ratio (∼156.18 dB), 3 dB cut-off frequency (∼36.16 GHz), and response time of 9.4 ps at 77 K. Furthermore, the effects of different external biasing, light power intensity, and temperature are evaluated, suggesting a high QEext of 3337.70% with a bias of −0.5 V near room temperature.

Silver nanoparticle decorated polyaniline–zeolite nanocomposite material based non-enzymatic electrochemical sensor for nanomolar detection of lindane

Abstract: In this study, a silver nanoparticle decorated polyaniline-nanocrystalline zeolite organic–inorganic hybrid material was synthesized. The material was characterized by the complementary combination of X-ray diffraction, N2-adsorption, scanning/transmission electron microscopy, and thermogravimetric analysis. An electrochemical sensor based on the silver nanoparticle decorated polyaniline-nanocrystalline zeolite was developed for the nanomolar detection of lindane in an aqueous solution of methanol with high electro-catalytic activity, stability, sensitivity, and selectivity. The sensor exhibited a wide linear range from 10 nM to 900 μM with a limit of detection of 5 nM under the optimum conditions. The analytical performance of the developed sensor was demonstrated for the determination of lindane in different water bodies with satisfactory recovery.

Fluorometric sensing of Hg2+ ions in aqueous medium by nano-aggregates of a tripodal receptor

Abstract: Two new tripodal receptors (1–2) have been synthesized and characterized by various spectroscopic techniques. The nano-aggregates of 1 and 2 (N1 and N2) have been prepared by a re-precipitation method in aqueous medium and have shown different photo-physical properties. Nano-aggregates of 1 (N1) can selectively recognize Hg(2+) in aqueous medium in the presence of other metal ions with enhancement in fluorescent intensity. The response was linearly proportional to the concentration of Hg(2+) in the range 0–10 μM with a detection limit of 2.4 nM. The mechanism of selective binding of Hg(2+) by N1 has also been supported by theoretical studies. To the best of our knowledge, this work represents the first report on substituted thiourea based nano-aggregates for nano-molar detection of mercury in aqueous medium.