National Chemical Laboratory

About: National Chemical Laboratory is a facility organization based out in Pune, Maharashtra, India. It is known for research contribution in the topics: Catalysis & Nanoparticle. The organization has 8891 authors who have published 14837 publications receiving 387600 citations.

A Versatile CuII Metal–Organic Framework Exhibiting High Gas Storage Capacity with Selectivity for CO2: Conversion of CO2 to Cyclic Carbonate and Other Catalytic Abilities

Abstract: A linear tetracarboxylic acid ligand, H4 L, with a pendent amine moiety solvothermally forms two isostructural metal-organic frameworks (MOFs) LM (M=ZnII , CuII ). Framework LCu can also be obtained from LZn by post- synthetic metathesis without losing crystallinity. Compared with LZn , the LCu framework exhibits high thermal stability and allows removal of guest solvent and metal-bound water molecules to afford the highly porous, LCu '. At 77 K, LCu ' absorbs 2.57 wt % of H2 at 1 bar, which increases significantly to 4.67 wt % at 36 bar. The framework absorbs substantially high amounts of methane (238.38 cm3 g-1 , 17.03 wt %) at 303 K and 60 bar. The CH4 absorption at 303 K gives a total volumetric capacity of 166 cm3 (STP) cm-3 at 35 bar (223.25 cm3 g-1 , 15.95 wt %). Interestingly, the NH2 groups in the linker, which decorate the channel surface, allow a remarkable 39.0 wt % of CO2 to be absorbed at 1 bar and 273 K, which comes within the dominion of the most famous MOFs for CO2 absorption. Also, LCu ' shows pronounced selectivity for CO2 absorption over CH4 , N2 , and H2 at 273 K. The absorbed CO2 can be converted to value-added cyclic carbonates under relatively mild reaction conditions (20 bar, 120 °C). Finally, LCu ' is found to be an excellent heterogeneous catalyst in regioselective 1,3-dipolar cycloaddition reactions ("click" reactions) and provides an efficient, economic route for the one-pot synthesis of structurally divergent propargylamines through three-component coupling of alkynes, amines, and aldehydes.

Ultra-thin V2O5 nanosheet based humidity sensor, photodetector and its enhanced field emission properties

Abstract: We report the synthesis of V2O5 nanosheets by a simple hydrothermal method. The as synthesized V2O5 nanosheets were characterized by Raman spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM) and UV-Vis spectroscopy. The humidity sensing behaviors were investigated in the range of 11–97% relative humidity (RH) at room temperature. The maximum sensitivity of 45.3%, response time of ∼4 min and recovery time of ∼5 min were observed for the V2O5 nanosheet based sensor. We also demonstrated the V2O5 nanosheets as an ultra-violet photodetector with a sensing response time of ∼65 s and recovery time of ∼75 s with a maximum photoresponsivity of ∼6.2%. Further, we have also carried out field emission (FE) investigations of V2O5 nanosheets under a planar “Diode” assembly in an ultrahigh vacuum (UHV) chamber at a base pressure of ∼1 × 10−8 mbar. The turn on fields required to draw field emission current densities of 1 μA cm−2 and 10 μA cm−2 are found to be 1.15 V μm−1 and 1.72 V μm−1, respectively. We achieved a maximum field emission current density of 1.532 mA cm−2 at an applied electric field of 3.2 V μm−1. The field enhancement factors calculated from the slope of the Fowler–Nordheim (F–N) plot are found to be 8530 and 3530 at low field and high field regions, respectively. Our results open up several avenues towards the successful utilization of V2O5 nanosheets and other metal oxide nanosheets for various nanoelectronics device applications including sensors, photodetector and flat panel displays.

Facile synthesis and electrochemical evaluation of PANI/CNT/MoS2 ternary composite as an electrode material for high performance supercapacitor

Abstract: Synthesis of a novel ternary composite consisting of polyaniline (PANI), functionalized multi-walled carbon nanotubes (CNTs) and molybdenum disulfide (MoS 2 ), via an in-situ polymerization method is reported Detailed structural and electrochemical characterization shows that incorporation of a small amount of MoS 2 in PANI/CNT composite tends to eliminate agglomeration problem of CNT The PANI/CNT/MoS 2 ternary composite reaches a specific capacitance of 350 F/g at the current density 1 A/g corresponding to a 5% MoS 2 content This ternary composite shows good cycling stability even at a higher energy density of 10 A/g Further, PANI/CNT/MoS 2 composite electrode shows higher energy density (777 Wh/kg) and power density (2140 W/kg) as compared to PANI/CNT composite without MoS 2