Indian Association for the Cultivation of Science

About: Indian Association for the Cultivation of Science is a education organization based out in Kolkata, India. It is known for research contribution in the topics: Catalysis & Excited state. The organization has 3867 authors who have published 10457 publications receiving 220098 citations.

Ionic liquid integrated multiwalled carbon nanotube in a poly(vinylidene fluoride) matrix: formation of a piezoelectric β-polymorph with significant reinforcement and conductivity improvement.

Abstract: Multiwalled carbon nanotubes (MWNTs) are functionalized covalently with ionic liquid (IL, 3-aminoethyl imidazolium bromide) which helps good dispersion of IL-functionalized MWNTs (MWNT-IL) in the poly(vinylidene fluoride) (PVDF) matrix. Analysis of transmission electron microscopy (TEM) micrographs suggests ∼10 nm coating thickness of MWNTs by ILs, and the covalent linkage of ILs with MWNTs is confirmed from FT-IR and Raman spectra. PVDF nanocomposites with full β-polymorphic (piezoelectric) form are prepared using MWNT-IL by both the solvent cast and melt-blending methods. The FE-SEM and TEM micrographs indicate that IL-bound MWNTs are homogeneously dispersed within the PVDF matrix. Increasing MWNT-IL concentration in the composites results in increased β polymorph formation with a concomitant decrease of the α polymorph, and a 100% β polymorph formation occurs for 1 wt % MWNT-IL in both the fabrication conditions. A differential scanning calorimetry (DSC) study shows that the MWNT-ILs are an efficient n...

Stability and Performance of CsPbI2Br Thin Films and Solar Cell Devices

Abstract: In this manuscript, the inorganic perovskite CsPbI2Br is investigated as a photovoltaic material that offers higher stability than the organic–inorganic hybrid perovskite materials. It is demonstrated that CsPbI2Br does not irreversibly degrade to its component salts as in the case of methylammonium lead iodide but instead is induced (by water vapor) to transform from its metastable brown cubic (1.92 eV band gap) phase to a yellow phase having a higher band gap (2.85 eV). This is easily reversed by heating to 350 °C in a dry environment. Similarly, exposure of unencapsulated photovoltaic devices to water vapor causes current (JSC) loss as the absorber transforms to its more transparent (yellow) form, but this is also reversible by moderate heating, with over 100% recovery of the original device performance. NMR and thermal analysis show that the high band gap yellow phase does not contain detectable levels of water, implying that water induces the transformation but is not incorporated as a major componen...

A New Triazine-Based Covalent Organic Framework for High-Performance Capacitive Energy Storage.

Abstract: The new covalent organic framework material TDFP-1 was prepared through a solvothermal Schiff base condensation reaction of the monomers 1,3,5-tris-(4-aminophenyl)triazine and 2,6-diformyl-4-methylphenol. Owing to its high specific surface area of 651 m2 g−1, extended π conjugation, and inherent microporosity, TDFP-1 exhibited an excellent energy-storage capacity with a maximum specific capacitance of 354 F g−1 at a scan rate of 2 mV s−1 and good cyclic stability with 95 % retention of its initial specific capacitance after 1000 cycles at 10 A g−1. The π-conjugated polymeric framework as well as ionic conductivity owing to the possibility of ion conduction inside the micropores of approximately 1.5 nm make polymeric TDFP-1 a favorable candidate as a supercapacitor electrode material. The electrochemical properties of this electrode material were measured through cyclic voltammetry, galvanic charge–discharge, and electrochemical impedance spectroscopy, and the results indicate its potential for application in energy-storage devices.

Nitrogen-rich porous covalent imine network (CIN) material as an efficient catalytic support for C–C coupling reactions

Abstract: In an effort to expand the realm of possibilities of nitrogen-rich porous materials that could be used in catalysis, herein we report the synthesis of a new highly nitrogen rich (ca. 45%) porous covalent imine network (CIN-1) material employing simple Schiff base chemistry and further grafting its surface with palladium. Pd-loaded CIN-1 support acts as a truly heterogeneous catalyst towards Suzuki C–C coupling reaction between aryl halides with arylboronic acids. High surface area and excellent accessibility of the catalytic sites make it very efficient for heterogeneous catalysis. The stability of the catalyst due to intimate contact between nitrogen-rich organic support and metal allows several reuses with only a minor loss in catalytic activity.