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In this work, we have synthesized composites of BiOCl with carbon nanotubes (CNTs) via a hydrothermal method. Different compositions of CNTs were used to study their influence on the physicochemical properties of BiOCl. Based on the interesting results obtained, various significant correlations were made. This study explored how use of CNTs and different hydrothermal crystallization conditions can influence the photocatalytic activity of composites. The CNTs have an impact on the primary crystallite size and morphology of BiOCl. Also, a higher degree of crystallization was obtained in the case of samples containing CNTs. However, in some cases, the synthesis parameters such as high temperature and longer duration also promoted crystallinity in BiOCl/CNT samples. Further, the samples were investigated for their photocatalytic activity to study the photodegradation of RhB and phenol, as model pollutants, under visible and UV light, respectively. The maximum degradation efficiency of 83% for RhB under visible light and almost 40% for phenol under UV light was obtained using BiOCl/CNT composites. Surprisingly, pure BiOCl showed higher performance for the removal of both the pollutants. This is why some comparisons and correlations between the structural and optical properties of BiOCl and CNTs were made. Finally, this study illustrates how a nanostructure like conductive multiwalled carbon nanotubes can sometimes have detrimental effects on the overall photocatalytic properties of a photocatalyst like BiOCl under certain conditions. Therefore, understanding the synergy between physico-chemical properties of BiOCl and nanostructured-modifiers like CNTs could help in designing a photocatalyst system which could benefit wastewater treatment.

The novel photoactive membranes have grabbed the attention in the field of environmental protection by employing wastewater treatments and the removal of microorganisms or organic pollutants from wastewater. Here we present a promising self-supported photoactive hybrid membrane for future antimicrobial and water treatment applications. In this study, the efficiency of bacterial cellulose (BC) - zinc oxide (ZnO) - multi walled carbon nanotube (MWCNT) hybrid membranes in the adsorption and photocatalytic degradation of methylene blue (MB) under UV radiation and the removal of Escherichia coli (E. coli) was investigated. It was found that the photocatalytic efficiency is strongly dependent on both the preparation method and the amount of ZnO-MWCNT additives loaded into the hybrid membranes. The characterization of BC-ZnO-MWCNT membranes was done using scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), and X-ray micro computed tomography (μCT) to study the morphological and porosity aspect of the prepared-membranes. The promising results of this study could provide a new pathway in the field of photocatalysed-based water treatment technology by the application of hybrid membranes.

Reaction of [Al(OPri)3] with K(OPri), in 1:1 molar ratio in refluxing anhydrous tetrahydrofuran yields a polymeric complex [(THF)K(μ-OPri)2Al(μ-OPri)2]n. The complex is characterized by spectroscopic studies and single crystal X-raydiffraction analysis.

In this work, we have prepared BiOI/CNT composites by hydrothermal method and studied the impact of CNT and hydrothermal treatment conditions (temperature and time) simultaneously on phenomena such as crystallization. The samples were studied using X-ray Diffraction (XRD), nitrogen sorption (Brunauer–Emmett–Teller (BET) specific surface areas), Scanning Electron Microscopy assisted with Energy Dispersive X-Ray spectroscopy (SEM-EDX), High Resolution Transmission Electron Microscopy (HRTEM), UV–vis Diffuse Reflectance spectroscopy (DRS), Raman spectroscopy and photoluminescence spectroscopy (PL). The different heat treatments applied and varied amount of CNT was found to have a profound effect on the structural, morphological, compositional and optical properties of the prepared composites. The distinguishable changes in the above-mentioned properties were clearly visible for the samples prepared at higher temperature and longer duration (150 °C, 6.30 h). Surprisingly, the presence of other phases of BiOI, such as Bi7O9I3, Bi4O5I2, Bi5O7I, also co-existed at the same time, although in low amount. Finally, for the study, the photocatalytic efficiency of the prepared samples was tested for phenol and RhB, as model pollutants, under visible light irradiation for 240 min and 120 min, respectively. The results revealed that the composites prepared at higher temperature with longer duration showed superior performance for the photodegradation of phenol and RhB. Additionally, the composites performed better than their respective reference samples in each case. Interestingly, the introduction of CNT promoted the crystallinity in the composites and promising results for the removal of phenol and RhB were achieved by the use of low power ordinary visible lamps.

Pharmaceutical effluents released from industries are accountable to deteriorate the aquatic and soil environment through indirect toxic effects. Microbes are adequately been used to biodegrade pharmaceutical industry wastewater and present study was envisaged to determine biodegradation of pharmaceutical effluent by Micrococcus yunnanensis. The strain showed 42.82% COD (Chemical oxygen demand) reduction before optimization. After applying Taguchi's L8 array as an optimization technique, the biodegradation rate was enhanced by 82.95% at optimum conditions (dextrose- 0.15%, peptone 0.1%, inoculum size 4% (wv−1), rpm 200, pH 8 at 25 °C) within 6 h. The confirmation of pharmaceuticals degradation was done by 1H NMR (Nuclear magnetic resonance) studies followed by elucidation of transformation pathways of probable drugs in the effluent through Q-Tof-MS (Quadrupole Time of Flight- Mass Spectrometry). The cytotoxicity evaluation of treated and untreated wastewater was analyzed on Human Embryonic Kidney (HEK 293) cells using Alamar Blue assay, which showed significant variance.

Bismuth oxybromide (BiOBr) is a novel visible light photocatalyst and when combined with multiwalled carbon nanotubes (CNT), it could lead to low electron/hole recombination rates, thus enhancing its photocatalytic activity. In this work, hierarchal BiOBr and BiOBr/CNT composites were successfully synthesized via hydrothermal method. The samples prepared were characterized for structural, morphological and optical properties via XRD, SEM, TEM and DRS. The influence of carbon nanotubes on various properties of BiOBr were studied and correlated. The impact of synthesis parameters (time and temperature) on structural properties was also studied. The photocatalytic degradation of phenol as model pollutant was carried out under visible light source to determine its photocatalytic activity. It was found that the presence of CNTs induced a growth in the crystallite size of the particles, which somewhat lowered the photocatalytic activity. As the CNT content increased in the sample so does the activity, due to the CNTs' visible light absorption capacity. Furthermore, a crystal orientation changes (crystallographic plane of (003)) were induced by varying several parameters, which were found to be influencing the activity as well, while the formation of Bi6O6(OH)3(NO3)3·1.5H2O was also observed. Its presence enhanced the photocatalytic activity but induced an instability problem.

Modification of [VO(OPri)3] with oximes in different molar ratios, yielded new class of vanadia precursors, [VO{OPri}3−n{L}n] {where, n = 1–3 and LH = C9H16C=NOH (1–3) and (CH3)2C=NOH (4–6)}.All the products are yellow in colour. (1) and (2) are liquid/viscous liquid, while others are solids. Molecular weight measurements of all these derivatives and the ESI-mass spectral studies of (1), (2), (3) and (5) indicate their monomeric nature. 1H and 13C{1H} NMR spectra suggest that the oximato moieties are monodentate in solution which was further confirmed by the 51V NMR signals, appeared in the region expected for tetra-coordinated oxo-vanadium atoms. On ageing, a disproportionation reaction occurs in (1) and some crystals appeared. Single crystal X-ray diffraction analyses of the crystals obtained from (1) as well as from (3) were found to be the same and indicate the presence of side-on {dihapto η 2-(N, O)} binding modes of the oximato ligands, leading to the formation of seven coordination environment around the vanadium atom. Thermogravimetric curve of (1) exhibits multi-step decomposition with the formation of V2O5 as the final product at ~850 °C. Sol–gel transformation of (3) yielded (a) VO2 sintered at 300 °C and (b) V2O5 at 600 °C. Similarly, sol–gel transformations of (1) and (2) yielded V2O5 (c) and (d) at 600 °C, respectively. Formation of monoclinic phase in (a) and orthorhombic phase in (b), (c) and (d) were confirmed by powder XRD patterns.

Non-aqueous reactions of aluminum isopropoxide with 8-hydroxyquinoline (Hq = HONH6C9) in 1:1, 1:2 and 1:3 molar ratios in anhydrous benzene yield complexes of the type [qnAl(OPri)3−n] {where n = 1 (1), n = 2 (2), n = 3 (3)}. Progress of the reactions were monitored by estimating liberated 2-propanol in benzene-2-propanol azeotrope by oxidimetric method. All the products were fluorescent green powders, sparingly soluble in CHCl3. They were characterized by elemental analysis, FT-IR and (1H, 13C and 27Al) NMR studies. The ESI mass spectral studies indicate dimeric nature for (1) and (2) and monomeric nature for the compound (3). The XRD spectra of (1–3) showed crystalline nature with the average particle size of 45, 32 and 27 nm respectively, as evaluated from Debye–Scherrer equation. The XRD spectrum of (3) also suggests the formation of β-crystalline polymorphs of Alq3. The SEM images appear to indicate granular morphology for (1) and formation of cylindrical shaped rods for (2) and (3). Sol–gel hydrolysis of (1), (2) or (3) in presence of a strong acid as well as of the precursor, Al(OPri)3,without acid or base catalyst, followed by sintering at 950 °C yielded tetragonal primitive phase of nano-sized δ-alumina in all the cases, as reflected by their powder X-ray diffraction pattern. The IR, SEM and EDX studies also support the formation of transition alumina.

Reactions of bis(N-phenylsalicylidene iminato)aluminium-di-μ-isopropoxo-di-isopropoxo aluminium(III), [C 6 H 4 O{CH=N(C 6 H 4 )}] 2 Al(μ-OPr i ) 2 A(OPr i ) 2 with glycols in 1:1 molar ratio in refluxing anhydrous benzene yieldedbinuclear complexes of the type, [C 6 H 4 O{CH=N(C 6 H 5 ))} 2 Al(μ-OPr i ) 2 Al(O-G-O) [where G = (CH 2 ) 2 , CH 2 CH(CH 3 ), CH 2 CH(C 2 H 5 ), CH(CH 3 )CH(CH 3 ), (CH 2 ) 5 , C(CH 3 ) 2 CH 2 CH(CH 3 ), (CH 2 ) 6 ],respectively. All these binuclear complexes have been characterised by elemental analysis, molecular weight measurements and spectroscopic(IR and NMR) studies.

Some Schiff’s base complexes of aluminum(III) of the type (CH3COCHCOCH3)2Al(µ-OPri)2AlLn(OPri)2-n [where LH=OHC(R)=CHC(R′)=NC6H5; R=R′=CH3,C6H5; R=CH3, R′=C6H5; LH=C6H4(OH)CH=NC6H5 and n=1 or 2] were prepared and characterized by various spectroscopic techniques. The molecular weight measurements indicated their binuclear nature. The 27Al nuclear magnetic resonance spectra of representative compounds [(CH3COCHCOCH3)2Al(µ-OPri)2Al{OC(C6H5)=CHC(C6H5)=NC6H5}(OPri)] [3] and [(CH3COCHCOCH3)2 Al(µ-OPri)2Al{OC(CH3)=CHC(CH3)=NC6H5}2] [6] suggest the presence of aluminum(III) atoms in different coordination states.

A novel heterocyclic derivative of aluminium(III) [C6H4O{CHN(C6H5)}]2Al(μ-OPri)2Al(OPri)21 has been synthesized by the reaction of aluminium isopropoxide with N-phenylsalicylidene imine in 1 ∶ 1 molar ratio in refluxing anhydrous benzene. Reactions of 1 with alkoxyalkanols in 1 ∶ 1 and 1 ∶ 2 molar ratios in refluxing anhydrous benzene yielded binuclear complexes of the types, [C6H4O{CHN(C6H5)}]2Al(μ-OPri)2Al(OCH2CH2OR)(OPri) and [C6H4O{CHN(C6H5)}]2Al(μ-OPri)2Al(OCH2CH2OR)2 (where RCH3, C2H5 and C4H9n), respectively. All of these binuclear complexes have been characterized by elemental analysis, molecular weight measurements, and spectral studies. The FAB mass spectrum and 27Al NMR spectrum of 1 indicate that it is a discrete unsymmetrical dimer containing four- and six-coordinated aluminium(III) atoms as confirmed by its single crystal X-ray structure.