Sharifah Mohamad

Bio: Sharifah Mohamad is an academic researcher from University of Malaya. The author has contributed to research in topics: Ionic liquid & Extraction (chemistry). The author has an hindex of 27, co-authored 121 publications receiving 2200 citations. Previous affiliations of Sharifah Mohamad include Universiti Putra Malaysia & King Abdulaziz University.

Synthesis and Characterization of the Inclusion Complex of β-cyclodextrin and Azomethine

Abstract: A β-cyclodextrin (β-Cyd) inclusion complex containing azomethine as a guest was prepared by kneading method with aliquot addition of ethanol. The product was characterized by Fourier Transform Infrared (FTIR) spectrometer, 1H Nuclear Magnetic Resonance (1H NMR) and Thermogravimetric Analyzer (TGA), which proves the formation of the inclusion complex where the benzyl part of azomethine has been encapsulated by the hydrophobic cavity of β-Cyd. The interaction of β-Cyd and azomethine was also analyzed by means of spectrometry by UV-Vis spectrophotometer to determine the formation constant. The formation constant was calculated by using a modified Benesi-Hildebrand equation at 25 °C. The apparent formation constant obtained was 1.29 × 104 L/mol. Besides that, the stoichiometry ratio was also determined to be 1:1 for the inclusion complex of β-Cyd with azomethine.

SrTiO₃ Nanocube-Doped Polyaniline Nanocomposites with Enhanced Photocatalytic Degradation of Methylene Blue under Visible Light.

Abstract: The present study highlights the facile synthesis of polyaniline (PANI)-based nanocomposites doped with SrTiO₃ nanocubes synthesized via the in situ oxidative polymerization technique using ammonium persulfate (APS) as an oxidant in acidic medium for the photocatalytic degradation of methylene blue dye. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), UV⁻Vis spectroscopy, Brunauer⁻Emmett⁻Teller analysis (BET) and Fourier transform infrared spectroscopy (FTIR) measurements were used to characterize the prepared nanocomposite photocatalysts. The photocatalytic efficiencies of the photocatalysts were examined by degrading methylene blue (MB) under visible light irradiation. The results showed that the degradation efficiency of the composite photocatalysts that were doped with SrTiO₃ nanocubes was higher than that of the undoped polyaniline. In this study, the effects of the weight ratio of polyaniline to SrTiO₃ on the photocatalytic activities were investigated. The results revealed that the nanocomposite P-Sr500 was found to be an optimum photocatalyst, with a 97% degradation efficiency after 90 min of irradiation under solar light.

Synthesis and characterization of Co3O4 nanocube-doped polyaniline nanocomposites with enhanced methyl orange adsorption from aqueous solution

Abstract: In the present study, Co3O4 nanocube-doped polyaniline nanocomposites have been successfully synthesised via an in situ oxidative polymerisation technique using ammonium persulfate (APS) as an oxidant in acidic medium for efficient removal of methyl orange (MO) from aqueous solution. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Brunauer–Emmett–Teller analysis (BET) and Fourier transform infrared spectroscopy (FT-IR) measurements were used to characterise the prepared nanocomposites. The adsorption efficiencies of the PANI homopolymer and Co3O4 nanocube-doped nanocomposites were evaluated by monitoring the adsorption of methyl orange model dye from aqueous solution. The results revealed that the adsorption efficiency of the nanocomposites that were doped with Co3O4 nanocubes was higher than that of the undoped PANI and the adsorption kinetics followed a pseudo-second order reaction. Moreover, the nanocomposite with 4 wt% Co3O4 nanocubes with respect to aniline exhibited a superior adsorption capacity (107 mg g−1) as compared to other absorbents.

Synthesis of Polyaniline-Coated Graphene Oxide@SrTiO₃ Nanocube Nanocomposites for Enhanced Removal of Carcinogenic Dyes from Aqueous Solution.

Abstract: The present investigation highlights the synthesis of polyaniline (PANI)-coated graphene oxide doped with SrTiO₃ nanocube nanocomposites through facile in situ oxidative polymerization method for the efficient removal of carcinogenic dyes, namely, the cationic dye methylene blue (MB) and the anionic dye methyl orange (MO). The presence of oxygenated functional groups comprised of hydroxyl and epoxy groups in graphene oxide (GO) and nitrogen-containing functionalities such as imine groups and amine groups in polyaniline work synergistically to impart cationic and anionic nature to the synthesised nanocomposite, whereas SrTiO₃ nanocubes act as spacers aiding in segregation of GO sheets, thereby increasing the effective surface area of nanocomposite. The synthesised nanocomposites were characterised by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The adsorption efficiencies of graphene oxide (GO), PANI homopolymer, and SrTiO₃ nanocubes-doped nanocomposites were assessed by monitoring the adsorption of methylene blue and methyl orange dyes from aqueous solution. The adsorption efficiency of nanocomposites doped with SrTiO₃ nanocubes were found to be of higher magnitude as compared with undoped nanocomposite. Moreover, the nanocomposite with 2 wt % SrTiO₃ with respect to graphene oxide demonstrated excellent adsorption behaviour with 99% and 91% removal of MB and MO, respectively, in a very short duration of time.

Ultracapacitors: Why, How, and Where is the Technology

Abstract: The science and technology of ultracapacitors are reviewed for a number of electrode materials, including carbon, mixed metal oxides, and conducting polymers. More work has been done using microporous carbons than with the other materials and most of the commercially available devices use carbon electrodes and an organic electrolytes. The energy density of these devices is 3¯5 Wh/kg with a power density of 300¯500 W/kg for high efficiency (90¯95%) charge/discharges. Projections of future developments using carbon indicate that energy densities of 10 Wh/kg or higher are likely with power densities of 1¯2 kW/kg. A key problem in the fabrication of these advanced devices is the bonding of the thin electrodes to a current collector such the contact resistance is less than 0.1 cm2. Special attention is given in the paper to comparing the power density characteristics of ultracapacitors and batteries. The comparisons should be made at the same charge/discharge efficiency.

Modelling and Interpretation of Adsorption Isotherms

Abstract: The need to design low-cost adsorbents for the detoxification of industrial effluents has been a growing concern for most environmental researchers. So modelling of experimental data from adsorption processes is a very important means of predicting the mechanisms of various adsorption systems. Therefore, this paper presents an overall review of the applications of adsorption isotherms, the use of linear regression analysis, nonlinear regression analysis, and error functions for optimum adsorption data analysis.