Dilbag Singh Rana

Hexagonal cadmium oxide nanodisks: Efficient scaffold for cyanide ion sensing and photo-catalytic applications

Herein, we report the large-scale low-temperature aqueous solution based synthesis of hexagonal-shaped cadmium oxide (CdO) nanodisks. The synthesized nanodisks were characterized in detail to investigate the morphological, structural, optical and compositional properties using various analytical tools. The detailed characterizations revealed that the synthesized CdO nanodisks are grown in high-density, possessing well-crystallinity with cubic crystal phase and exhibiting good optical properties. Further, the prepared CdO nanodisks were used as efficient scaffold for cyanide ion sensor and photocatalyst applications. A luminescent sensor for the determination of cyanide ion in aqueous solution was fabricated based on synthesized CdO nanodisks. The fabricated luminescent sensor exhibited an extremely low detection limit (~1.40μmolL(-1)) towards cyanide ion which is significantly lower than the maximum permitted value of cyanide ion by United States Environmental Protection Agency (EPA) for drinking water (7.69μmolL(-1)). The interference studies of the fabricated sensor also demonstrate excellent selectivity towards cyanide ions compared to other coexisting ions. As a photocatalyst, the synthesized CdO nanodisks exhibited high photodegradation (~99.7%) of toxic methyl orange dye just in 90min using 0.25g of CdO nanodisks.

Solvation Behaviour of some Copper (I), Silver (I) and Tetraalkylammonium Salts in Actonitrile + Adiponitrile Mixtures

Abstract Solvation behaviour of some copper (I), silver (I) and tetrabutylammonium salts has been investigated in binary mixtures of acetonitrile and adiponitrile containing 100, 90, 80, 70, 60 and 50 mol % AN at 298 K using molar conductance and viscosity measurements. The conductance data have been analyzed by using the Shedlovsky method to calculate limiting molar conductance (Λo) of the electrolytes. The solvated radii for various ions indicate that tetrabutylammonium (Bu4N+) and tetraphenylborate (BPh4–) are not solvated in all AN+ADN mixtures. The anions are poorly solvated but Cu+ and Ag+ are highly solvated in AN+ADN mixtures. The extent of solvation of Cu+ is greater then that of Ag+. The solvation of these both ions increases in ADN rich region of the mixtures. The viscosity data have been analyzed by using the Jones-Dole equation to calculate viscosity B-coefficients of electrolytes. The ionic B± coefficients for individual ions have been evaluated. The results show that anions are weakly solvated in whole composition range of AN + ADN mixtures. The B+ coefficients for Cu+ and Ag+ increase with increase in ADN composition i.e. these are better solvated in ADN rich region of binary mixtures. The viscosity results are in good agreement with the results obtained from the conductance studies.

Volumetric and Compressibility Studies of Some 1 : 1 Electrolytes in the Presence of Furosemide Using Transport Properties

Abstract Sound velocities (v) and densities (d) for some alkali metal chlorides in aqueous solutions containing 0, 0.001, 0.005 and 0.01 M Furosemide have been measured at different temperature (293, 303 and 313 K). The data was used to apparent molar volume (ϕv) and apparent molar adiabatic compressibility (ϕk). The above calculated parameters were found to be sensitive to the prevailing in the Furosemide-Na+/K+-water system. These parameters have been examined as a function of Furosemide concentration and temperature to understand the consequences of interactions between these two components. Debye Hückel limiting law is used for the assessment of the contributions of various types of solute-solvent interactions. Viscosity B-coefficients have also been evaluated for these salts in the presence of Furosemide. Jones–Dole viscosity equation is used to calculate viscosity B-coefficient which is known to provide information concerning the solvation of ions and their effects on the structure of the solvent in the near environment of the solute particles. It is related to measure the solute–solvent interaction and is interpreted in terms of the solvent structure-making and breaking effect of the electrolyte in solution. A reasonably good qualitative correlation is found to exist with regard to the Furosemide-Na+/K+ interaction obtained from the experimental data, from different techniques.

Isentropic Compressibility Studies of Some Salts in Acetonitrile + N,N-dimethylacetamide Mixtures at 298 K

Abstract Ultrasonic velocities and densities of some copper(I) and silver(I) salts have been measured in the concentration range 0.002–0.28 mol kg−1 in binary mixtures of acetonitrile (AN) + N,N-dimethylacetamide (DMA) containing 100, 80, 60, 40, 20 and 0 mol % AN at 298 K. The isentropic compressibility (Ks) and apparent molal isentropic compressibility in various solvent systems have been calculated by using ultrasonic velocity (u) and partial molal volume (Vφ) respectively. Limiting apparent molal isentropic compressibilities (Ks,φ0) for various salts have been evaluated from vs.m1/2 plots and split into the contributions of individual ions (Ks,φ0)±. The (Ks,φ0)± values for copper(I) and silver(I) ions are found to be negative over the entire composition range which indicate strong solvation of these complex ions. The (Ks,φ0)± values for these ions increase with increase in DMA composition shows that the extent of solvation increases with increase in DMA composition.

Transport Studies of Some 1:1 Copper(I) Perchlorate Complexes in Acetonitrile-Dimethylsulphoxide Mixtures

Abstract Solvation behaviour of some copper(I) perchlorate complexes has been investigated in binary mixtures of acetonitrile (AN) and dimethylsulphoxide (DMSO) containing 1.0, 0.8, 0.6, 0.4, 0.2 and 0 mol fraction of AN at 298 K by molar conductances and viscosity measurements. The conductance data have been analyzed by using the Shedlovsky method to calculate limiting molar conductance (Λo) and the viscosity data by the Jones–Dole equation to evaluate viscosity B-coefficients of various salts. Limiting ion conductances (λio), solvated radii (ri) and ionic viscosity B± coefficients in all solvent systems have been evaluated using Gill´s modification based on Bu4NBPh4 as a reference electrolyte. The studies show that all copper(I) complexes are solvated and the extent of solvation is stronger in AN and AN rich regions than in DMSO and DMSO rich regions. The ClO4- ion is poorly solvated in AN+DMSO mixtures. The viscosity results are in good agreement with the results obtained from the conductance studies.

Preparation of Some Novel Copper(I) Complexes and their Molar Conductances in Organic Solvents

Abstract Attempts have been made to prepare some novel copper(I) nitrate, sulfate, and perchlorate complexes. Molar conductances of these complexes have been measured in organic solvents like acetonitrile (AN), acetone (AC), methanol (MeOH), N,N-dimethylformamide (DMF), N,Ndimethylacetamide (DMA), and dimethylsulfoxide (DMSO) at 298 K. The molar conductance data have been analyzed to obtain limiting molar conductances (λ0) and ion association constants (KA) of the electrolytes. The results showed that all these complexes are strong electrolytes in all organic solvents. The limiting ionic molar conductances (λo± ) for various ions have been calculated using Bu4NBPh4 as reference electrolyte. The actual radii for copper(I) complex ions are very large and different in different solvents and indicate some solvation effects in each solvent system

A Comparative Nuclear Magnetic Resonance Study of the Solvation of CuClO4 in Binary Mixtures of Acetonitrile with Pyridine and Picolines at 298K

63Cu nuclear magnetic resonance (NMR) and viscosity studies of 0:064M CuClO4 solutions have been reported in binary mixtures of acetonitrile (AN) with pyridine (Py) and 2, 3, and 4-picolines (2,3,4-Pic) at 298 K using a Bruker 500 MHz NMR spectrometer and an Ubbelohde viscometer, respectively. Chemical shift d and linewidth D for the 63Cu signals have been recorded referenced to a 0:064M CuClO4 solution in anhydrous AN. The copper quadrupole coupling constants (e2Qq=h) have been calculated in all cases. The variation of the d and e2Qq=h values as a function of mol fraction of the co-solvent show that all these bases interact with Cu+ more strongly than AN. They replace AN from the Cu+ complexed with AN in the form [Cu(AN)4]+ and form a mixed complex of the type [Cu(AN)4-x(S)x]+ (x=1 - 4) where S stands for the base. At relatively high mole fraction of the co-solvents, the mixed solvated complex gradually changes to a more symmetrical complex of the type [Cu(S)4]+ which remains stable in the solution. The solvating effect of 2-Pic and 4-Pic is observed to be stronger than that of Py and 3-Pic.

Preparation, Characterization, X-Ray Structure Determination and Solution Properties of some Novel Copper(I) Bisulfate and Sulfate Salts and Their Stable Derivatives

Two highly unstable copper(I) salts, i. e. copper(I) bisulfate tetraacetonitrile, [Cu(CH3CN)4]HSO4, and dicopper(I) sulfate octaacetonitrile, [Cu(CH3CN)4]2SO4, and their stable derivatives with 2,9- dimethyl-1,10-phenanthroline (DMPhen) have been prepared in pure form and characterized by elemental, spectral and chemical analysis. Single-crystal X-ray studies of [Cu(CH3CN)4]HSO4 and its derivative [Cu(DMPhen)2]HSO4 have been carried out. The solution behavior of both of these salts and their derivatives have been investigated using UV/Vis, IR, 63Cu NMR spectroscopy and molar conductance in a number of non-aqueous solvents. Furthermore, a simple method for the preparation of Cu2SO4 is presented. Graphical Abstract Preparation, Characterization, X-Ray Structure Determination and Solution Properties of some Novel Copper(I) Bisulfate and Sulfate Salts and Their Stable Derivatives