Publications

In order to prepare fiber-type nanohybrid composites for electrochemical and antimicrobial applications, polypyrrole was combined with carboxymethylcellulose and multiwalled carbon nanotubes (PPy/CMC/MWCNTS). These composite materials were synthesized using ultrasonication and in situ polymerization. By using analytical methods, the structure and morphology of the synthesized nanohybrid composite material were confirmed. Slurry of fiber-type PPY/CMC/MWCNT composites synthesized in ethanol was deposited as a thin-uniform layer with conductive nafion (5% ethanolic solution of nafion) binder. Based on electrochemical measurements in a phosphate buffer medium, Sb3+ ions have linear responses between 0.1 nM and 0.01 mM, which is known as linear dynamic range (LDR). A sensor’s sensitivity (22.4304 µAµM−1cm−2) is calculated using the LDR slope by considering the GCE surface area (0.0316 cm2). A signal-to-noise ratio of 3 is used to estimate the lower limit of detection which is equal to 96.82 ± 4.84 pM. Moreover, the antibacterial activity of the obtained polypyrrole/carboxymethylcellulose/MWCNT composite has also been evaluated “against Gram-positive bacteria B. subtilis along with S. aureus, as well as Gram-negative bacteria, P. aeruginosa along with Escherichia coli by utilizing” autoclave of agar media. In electrochemical analysis, the proposed Sb3+ cationic sensor exhibits appreciable reproducibility, response time, stability, and outstanding outcome in analysis of real samples. In the field of metal ion sensor, this reliable method might be prospective in the recent future.

Spiro-type molecules have been extensively explored as hole-transporting materials (HTMs) in perovskite solar cells (PSCs). However, a closer look at the rule of design of such molecules is missing, and a combined experimental and theoretical study is needed. In this work, three spiro-[cyclopenta[1,2-b:5,4-b′]dithiophene-4,9′-fluorene] (SDTF) derivatives decorated with triphenylamine have been designed and synthesized. The thermal and optoelectronic properties, single-crystal structures, and charge-transport properties have been extensively investigated to reveal the impact of the linkage position of triphenylamine groups by combining experimental and theoretical methods, and the results are consistent with each other. Moreover, transfer integrals and reorganization energies in these molecules are also calculated to predict hole mobility. Our comprehensive studies show that SDTF-2 with a suitable energy alignment, good hole injection/transportability, and high theoretical hole mobility can be employed for efficient perovskite solar cells, achieving a high power conversion efficiency of 19.3%. In addition, first-principle calculations reveal that the strong interactions between SDTF-2 and the perovskite surface can facilitate fast hole extraction. Our way of study has provided useful information as part of the Materials Genome Initiative. We hope our investigation will offer a reliable path to predict or find the potential of novel spiro-type HTMs to become the alternative choice of spiro-OMeTAD.

Here, we have designed an efficient multipurpose photocatalytic system based on iron-doped tin oxide (Fe-SnO2) which exhibited excellent catalytic activity toward dyes degradation and hydrogen production. The synthesized photocatalyst was characterized using different spectroscopic techniques. Fe-SnO2 was tested in degradation of different dyes i.e., congo red (CR), acridine orange (ArO) and methyl orange (MO) and among these dyes, Fe-SnO2 was more efficient and selective toward CR which was degraded more than 95% in 30 min. Further, the catalytic efficiency of Fe-SnO2 was also evaluated toward photocatalytic hydrogen generation from aqueous solutions of methanol, ethanol, propanol, potassium hydroxide and Na2S + Na2SO3, where Fe-SnO2 displayed high catalytic activity toward hydrogen generation from methanol solution under sunlight. Moreover, the catalytic activity of Fe-SnO2 toward CR degradation and hydrogen production was optimized by using different combinations of operating conditions and no major loss in activity was observed upon running the same photocatalyst sample in different batches.

Highly dispersed Co nanoparticles on biomass Juncus derived carbon achieve superb nitrite reduction performances with a faradaic efficiency of 96.9% and an NH 3 yield of 2.8 mol h −1 g Co −1 . The catalytic mechanism is revealed by DFT calculations.

Three-coordinate copper halide complexes with a bidentate phosphine ligand have received much attention. Here, a series of three-coordinate dinuclear copper halide complexes containing a diphenylamino monodentate phosphine ligand, [CuX(dpnp)]2 (dpnp = N-[2-(diphenylphosphino)-4,5-dimethylphenyl]-N-phenylaniline, X = I (1), Br (2) and Cl (3)), were synthesized, and their molecular structures and photophysical properties were investigated. The structural analysis reveals that two copper(I) centers are bridged by two halogen ligands to form a dinuclear structure with a four-membered Cu2X2 ring. Crystal structures of 1–3 contain 1-D supramolecular arrays constructed by intermolecular C–H⋯π interactions. These complexes exhibit blue emission in the solid state at room temperature and have peak emission wavelengths at 483–487 nm with microsecond lifetimes (τ = 13.9–38.1 μs) and low emission quantum yields (<0.01%). The emission of complex 1 mainly originates from intraligand (IL) transition, whereas the emissions of complexes 2 and 3 are from a combination of MLCT, XLCT and IL transitions. The three complexes displayed good thermal stability.

Abstract With the use of traditional Haber‐Bosch N 2 fixation, a huge amount of CO 2 emission bring a huge burden to the environment. Electrochemical N 2 reduction provides an environmental‐friendly and sustainable alternative to NH 3 synthesis at ambient conditions. Herein, we report our recent experimental finding that Ag composited with TiO 2 can greatly improve the N 2 reduction reaction performance of TiO 2 toward ambient conversion. In 0.1 M Na 2 SO 4 (pH=7), such electrocatalyst achieves a large NH 3 yield rate of 14.88 μg h −1 mg −1 cat. with a Faradaic efficiency of 6.2 % at −0.70 V vs. reversible hydrogen electrode. Besides, it also demonstrates high electrochemical and structural stability for NH 3 generation.