Mohd Hasmizam Razali

Adsorption of methyl orange by synthesized and functionalized-CNTs with 3-aminopropyltriethoxysilane loaded TiO2 nanocomposites

This study aims to develop a highly efficient adsorbent material. CNTs are prepared using a chemical vapor deposition method with acetylene and synthesized mesoporous Ni-MCM41 as the carbon source and catalyst, respectively, and are then functionalized using 3-aminopropyltriethoxysilane (APTES) through the co-condensation method and loaded with commercial TiO2. Results of X-ray powder diffraction (XRD), Raman spectra, and Fourier transform infrared spectroscopy (FTIR) confirm that the synthesized CNTs grown are multi-walled carbon nanotubes (MWNTs). Transmission electron microscopy shows good dispersion of TiO2 nanoparticles onto functionalized-CNTs loaded TiO2, with the diameter of a hair-like structure measuring between 3 and 8xa0nm. The functionalized-CNTs loaded TiO2 are tested as an adsorbent for removal of methyl orange (MO) in aqueous solution, and results show that 94% of MO is removed after 10xa0min of reaction, and 100% after 30xa0min. The adsorption kinetic model of functionalized-CNTs loaded TiO2 follows a pseudo-second order with a maximum adsorption capacity of 42.85xa0mg/g. This study shows that functionalized-CNTs loaded TiO2 has considerable potential as an adsorbent material due to the short adsorption time required to achieve equilibrium.

Synthesis of multiwalled carbon nanotubes supported on M/MCM-41 (M = Ni, Co and Fe) mesoporous catalyst by chemical vapour deposition method

Aim of this research is to develop an effective way in producing multi-walled carbon nanotubes (MWNTs) via chemical vapour deposition method using acetylene as carbon source and synthesized mesoporous M/MCM-41 (Mu2009=u2009Ni, Co and Fe) as catalyst. The mesoporous MCM41 is synthesized by using sodium metasilicate as silica source of frameworks and cetyltrimethylammonium bromide as template. The effect of temperatures and growth times are investigated to produce MWNTs with high yield and high quality. The low-angle X-ray diffraction (XRD), Fourier transform infrared spectroscopy and scanning electron microscopy results verified the formation of MCM41. Meanwhile, high-angle XRD, Raman spectra and transmission electron microscopy results confirmed the synthesized carbon nanotubes at 600u2009°C and growth time for 30xa0min are multi-walled. The yield obtained is 1353xa0mg in 30xa0min. It shows that the MCM-41 has a promising potential to produce MWNTs at low cost and shorter duration.

Manganese Substituted Iron Titanate Particles with Enhancement Adsorption Capacity for Removal of Remazol Brilliant Blue R Dye

Manganese substituted iron titanate was successfully synthesized and characterized by x-ray diffraction and Fourier transformed infra-red to investigate the composition and to identify the chemical compound of this unique architecture. The materials were tested for adsorption of remazol brilliant blue R (RBBR) aqueous solution. The adsorptions were investigated at different pH which are pH 3, 4, dye concentration and manganese substituted iron titanate dosage. It was found that synthesized manganese substituted iron titanate particles can adsorbed 99% of 100 ppm RBBR dye at pH 2.

Synthesis and Electrical Conductivity of N-(3-(Trifluoromethyl)Benzylidine)Thiosemicarbazide towards Dyes Sensitized Solar Cell

Organic compound containing thiosemicarbazide moiety has been successfully synthesized. The new synthesized dyes, N-(3-(Trifluoromethylbenzaldehyde)benzylidine thiosemi- carbazide (3-TFT) was characterized by spectroscopic technique namely, CHNS elemental analysis, Fourier Transform Infra-Red analysis (FT-IR), UV-Visible analysis (UV-Vis), 1H and 13C Nuclear Magnetic Resonance (NMR). The thin films of this dye have been prepared using a spin coating technique and deposited on indium tin oxide (ITO) glass substrate. The main highlight was an electrical conductivity of thin films which was measured using four point probing system in a range of light intensity, 25 Wm-2 until 200Wm-2. The potential electrical conductivity of 3-TFT dye was found gradually increased until reached the maximum conductivity values of 0.1489 Scm-1 at light intensity of 100 Wm-2 in the most diluted concentration at 1x10-5M.

Nanostructured TiO2 Materials: Preparation, Properties and Potential Applications (3P’s)

Nanostructured materials are a new class of materials which provide one of the greatest potentials for improving performance and extended capabilities of products in a number of applications. In particular nanostructured TiO2 was used as photocatalysts, gas sensor, solar cells and nanocomposite biomaterials. For each of these applications, aspects such as surface morphology, crystallinity and chemistry of the titania-based materials are the key parameters to be settled for the process optimization. A series of nanostructured TiO2 materials (TiO2 nanotubes, TiO2 nanorods, TiO2 nanoparticles) was synthesized using simple hydrothermal methods. X-Ray Diffraction (XRD), Field Emission Scanning Electron microscope (FESEM) and Brunauer–Emmett–Teller (BET) surface area characterization was carried out to study the properties of synthesized nanostructured TiO2 materials. The performance of synthesized nanostructured TiO2 was evaluated for various applications such as photocatalyst for methyl orange (MO) degradation and anti-bacterial thin film for biomedical and food packaging. Among the nanostructured TiO2 materials, TiO2 nanotubes shows the highest activity regardless of their applications. This is probably due to their nanotubular morphology in which provided high surface area materials. The surface area of TiO2 nanotubes was found to be 226.52 m2/g. The outer and inner diameters of nanotubes are 4 nm and 10 nm, respectively with several hundred nanometers in length. Anatase TiO2 phase structure and crystallinity of TiO2 nanotubes supports the good performances of the nanostructured materials.

Study on Band Gap Energy of F Doped TiO 2 Nanotubes

Pure and F doped TiO2 nanotubes was synthesized using simple hydrothermal method. The hydrothermal was conducted using teflon-liner autoclave and maintained at 150oC for 24 hours. The characterization of synthesised product was carried out using x-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive of x-ray spectroscopy (EDX) and ultra violet – visible light diffuse reflectance spectroscopy (UV-Vis DRS) for band gap measurements. XRD patterns indicated that anatase TiO2 phase was remained after F doping suggested that fluorine was highly dispersed into TiO2 by substituted with O in the TiO2 lattice to formed TiO2-xFx solid solution. Morphology investigation using TEM found out small diameter of nanotubes structure within 8 – 10 nm of pure and F doped TiO2 nanotubes. The band gap energy (Eg) of both nanotubes samples were almost similar proposing that F doping does not modify the band gap energy.

Characterization of Nanostructured Titania and Titanate Materials Synthesized by Simple Hydrothermal Method

In this research, the effect of different hydrothermal treatment temperature (100, 150, and 200 °C) on the products obtained by hydrothermal method was studied. Various characterization techniques was carried out such as X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), energy dispersive of x-ray spectroscopy (EDX) and fourier transform infrared spectroscopy (FTIR). XRD analysis shows that titanate phase was formed at 150 and 200 °C hydrothermal treatment. On the other hand, at 100 °C anatase TiO2 phase structured was gained which is similar with the TiO2 precursor. Morphological study using FESEM revealed that nanofibers and nanorods samples obtained at 150 °C and 200 °C, respectively. At 100°C, irregular shaped particle was attained similar with TiO2 precursors. FTIR spectra for the all studied sample displayed three main broad peaks at the range of 3700-2800, and 1800-1400 assigned to –OH stretching and deformation mode due to H2O molecules and M-O stretching mode at 900-400 cm-1 assigned to Ti-O bond.

Mechanical and physicochemical properties study on gellan gum thin film prepared using film casting method

The GG thin films were prepared by film casting technique using gelzan (GG1) and kelcogel (GG2) respectively. The physical appearances of the thin films were observed and their mechanical and chemical properties were investigated. Chemical characterizations were done by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), UV-Vis Spectroscopy, and Scanning Electron Microscopy (SEM). Based on the ATR-FTIR result, GG1 and GG2 thin films show a broad peak in the range of 3600-3200u2005cm−1 assigned to –OH functional group. A broad peaks also was observed at 3000-2600u2005cm−1 and 1800-1600u2005cm−1 which are belong to –CH and C=O functional group, respectively. The UV-Vis Spectroscopy analysis shows that single absorption peak was observed at 260u2005nm for both films. For mechanical properties, GG1 thin film has high tensile strength (80±12), but low strain at break (2±1), on the other hand GG2 thin film has low tensile strength (3±0.08) but high strain at break (13±0.58). The Water Vapour Transmission Rates (WVTR) and swelling of GG1 and GG2 thin films were (422±113, 415±26) and (987±113, 902±63), respectively.The GG thin films were prepared by film casting technique using gelzan (GG1) and kelcogel (GG2) respectively. The physical appearances of the thin films were observed and their mechanical and chemical properties were investigated. Chemical characterizations were done by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), UV-Vis Spectroscopy, and Scanning Electron Microscopy (SEM). Based on the ATR-FTIR result, GG1 and GG2 thin films show a broad peak in the range of 3600-3200u2005cm−1 assigned to –OH functional group. A broad peaks also was observed at 3000-2600u2005cm−1 and 1800-1600u2005cm−1 which are belong to –CH and C=O functional group, respectively. The UV-Vis Spectroscopy analysis shows that single absorption peak was observed at 260u2005nm for both films. For mechanical properties, GG1 thin film has high tensile strength (80±12), but low strain at break (2±1), on the other hand GG2 thin film has low tensile strength (3±0.08) but high strain at break (13±0.58). The Water Vapour Transm...

Study on physicochemical properties of functionalized-MWNTs with 3-aminopropyltriethoxysilane loaded TiO2 nanoparticles

One of the exciting developments in science today is the design and synthesis of carbon nanotubes (CNTs) that possess novel properties and not exhibited by other individual organic and inorganic materials. CNTs are prepared using a chemical vapor deposition method with acetylene and synthesized mesoporous Ni-MCM41 as the carbon source and catalyst, respectively, and are then functionalized using 3-aminopropyltriethoxysilane (APTES) through the co-condensation method and loaded with commercial TiO2. Mesoporous Ni-MCM41 catalyst is first synthesized by hydrothermal method using sodium metasilicate as silica source and cetyltrimethylammonium bromide (CTABr) as a template. Results of Raman spectroscopy confirm that the synthesized carbon nanotubes are multi-walled. The type IV nitrogen adsorption-desorption isotherm and narrow pore size distribution proved that the functionalized-MWNTs loaded TiO2 is in mesopore range. Field Emission Scanning Electron Microscopy reveals that goodxa0dispersions of TiO2 nanoparti...

Characterization of hydrothermally synthesized nanocrystalline titanium dioxide and their potential application in dye sensitive solar cells (DSSCs)

Nanocrystalline titanium dioxide (TiO2) was successfully synthesized using simple hydrothermal method. Synthesized nanocrystalline TiO2 was characterized using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive of X-Ray (EDAX) and Fourier Transform Infra-Red (FTIR). XRD patterns showed sharp and narrow peaks belong to polycrystalline tetragonal anatase TiO2 phase. The crystallite size of TiO2 was found to be 20u2005nm calculated from (101) XRD peaks using scherrer equation. SEM observations revealed uniform distribution of spherical-shaped grains consists of titanium and oxygen elements as confirmed by EDX analysis. For potential application in dye sensitized solar cells (DSSCs), the electrical conductivity of nanocrystallite TiO2 thin film was measured using four point probe at different concentration of TiO2.Nanocrystalline titanium dioxide (TiO2) was successfully synthesized using simple hydrothermal method. Synthesized nanocrystalline TiO2 was characterized using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive of X-Ray (EDAX) and Fourier Transform Infra-Red (FTIR). XRD patterns showed sharp and narrow peaks belong to polycrystalline tetragonal anatase TiO2 phase. The crystallite size of TiO2 was found to be 20u2005nm calculated from (101) XRD peaks using scherrer equation. SEM observations revealed uniform distribution of spherical-shaped grains consists of titanium and oxygen elements as confirmed by EDX analysis. For potential application in dye sensitized solar cells (DSSCs), the electrical conductivity of nanocrystallite TiO2 thin film was measured using four point probe at different concentration of TiO2.