Nanocrystalline FeS and FeSe compounds were prepared by solvothermal decomposition of a precursor complex [Fe(3)(μ(3)-O)(μ(2)-O(2)CCH(2)Cl)(6)(H(2)O)(3)]NO(3)·H(2)O in the presence of thiourea and sodium selenite, respectively. The as-obtained products were characterized by X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and UV-vis spectroscopic techniques. Structural analyses revealed that the FeS and FeSe nanoparticles (NPs) are composed of needle-like and spherical particles, respectively. The FeS and FeSe NPs showed photocatalytic activity for the decomposition of rose bengal (RB) and methylene blue (MB) dyes under white light illumination. They also showed good catalytic activity toward oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H(2)O(2) and followed Michaelis-Menten kinetics. In addition, both FeS and FeSe NPs exhibited electrocatalytic activity toward reduction of hydrogen peroxide, which on immobilization on glassy carbon (GC) electrodes perform as amperometric sensors for detection of H(2)O(2). At pH 7.0, the FeS/GC showed a linear range for detection of H(2)O(2) from 5 to 140 μM, while for FeSe/GC the range was 5 to 100 μM.

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A new structure-directing agent, hexadecyl-2-pyridinyl-methylamine, L 16 , was prepared through Schiff base condensation between pyridine-2-carboxaldehyde and hexadecylamine followed by reduction of the imine with NaBH 4 . Mesoporous and supermicroporous tin oxide particles with crystalline pore walls were obtained through a low-temperature sol-gel synthesis process by using an anionic surfactant, sodium dodecylsulfate, and hexadecyl-2-pyridinyl-methylamine, respectively, as templates. Powder X-ray diffraction, transmission electron microscopy-energy-dispersive spectrometry, field emission scanning electron microscopy, CHN chemical analysis, N 2 sorption, 1 H and 13 C NMR, high-resolution mass spectrometry, Fourier transform infrared spectroscopy, and UV-vis absorption spectroscopic tools were employed to characterize L 16 and nanostructured SnO 2 materials. X-ray diffraction and transmission electron microscopy image analyses suggested that these porous materials have a wormhole-like disordered arrangement of pores, whereas the pore walls are crystalline. Nitrogen physisorption studies show high specific surface areas up to 555 m 2 g -1 , and the uniform nanoscale pore size distribution ranged from supermicropore to mesopores for these materials. These SnO 2 materials showed drastic reduction of dielectrics with the induction of porosity vis-à-vis bulk SnO 2 . These unique optical and electrical properties of porous SnO 2 materials over bulk SnO 2 could be attributed to the quantum confinement effect.

Creation of an innovative composite photocatalyst, to advance its performance, has attracted researchers to the field of photocatalysis. In this article, a new photocatalyst based on polyaniline/reduced graphene oxide (PANI/RGO) composites has been prepared via the in situ oxidative polymerization method employing RGO as a template. For thermoelectric applications, though a higher percentage (50 wt %) of RGO has been used, for photocatalytic activity, lesser percentages (2, 5, and 8 wt %) of RGO in the composite have given a significant outcome. Furthermore, photoluminescence (PL) spectra, time-resolved fluorescence spectra, and Brunauer–Emmett–Teller surface area analyses confirmed the improved photocatalytic mechanism. PANI/RGO composites under visible light irradiation exhibit amazingly improved activity toward the degradation of cationic and anionic dyes in comparison with pristine PANI or RGO. Here, a PANI/RGO composite, with 5 wt % RGO(PG2), has emerged as the best combination with the degradation percentages of 99.68, 99.35, and 98.73 for malachite green, rhodamine B, and congo red within 15, 30, and 40 min, respectively. Experimental findings show that the introduction of RGO can relieve the agglomeration of PANI nanoparticles and enhance the light absorption of the materials due to an increased surface area. Moreover, the PG2 composite also showed excellent photocatalytic activity to reduce noxious Cr(VI). The effective removal of Cr(VI) up to 94.7% at pH 2 was observed within only 15 min. With the help of the active species trapping experiment, a plausible mechanism for the photocatalytic degradation has been proposed. The heightened activity of the as-synthesized composite compared to that of neat PANI or RGO was generally because of high concentrations of • OH radicals and partly of • O 2 – and holes (h + ) as concluded from the nitroblue tetrazolium probe test and photoluminescence experiment. It is hoped that the exceptional photocatalytic performance of our work makes the conducting polymer-based composite an effective alternative in wastewater treatment for industrial applications.