Now showing 1 - 6 of 6
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Effect of polyethylene glycol and sodium dodecyl sulphate on microstructure and self-cleaning properties of graphene oxide/TiO2 thin film

2020-09-01 , Azani A. , Dewi Suriyani Che Halin , Kamrosni Abdul Razak , Mohd. Mustafa Al Bakri Abdullah , Norsuria Mahmed , Muhammad Mahyiddin Ramli , Mohd Arif Anuar Mohd Salleh , Mohd Fairul Sharin Abdul Razak , Ayu Wazira Azhari , Chobpattana V. , Kaczmarek L.

In this study, a sol gel procedure for preparation of TiO2 thin films with graphene oxide (GO) was developed. The effect of PEG and SDS addition on the microstructure of the films as well as the photocatalytic activity of the thin film was also investigated. The morphology and surface structure of the films were studied by SEM and AFM while the photocatalytic activity of the films was analyzed by measuring the degradation of methylene blue under sunlight irradiation using UV-Vis spectrophotometer. It was found that GO/TiO2 thin film with PEG shows a smaller and porous particle while GO/TiO2 thin film with SDS formed a very smooth surface and very fine particles. Therefore, in AFM analysis reveals that surface roughness decreases with the addition of PEG and SDS. Finally, the photocatalytic activity showed that GO/TiO2 thin film with SDS have the most effective self-cleaning property which degrade 64% of methylene blue that act as model of contaminants.

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Factors of Controlling the Formation of Titanium Dioxide (TiO2) Synthesized using Sol-gel Method - A Short Review

2022-01-24 , Kamrosni Abdul Razak , Dewi Suriyani Che Halin , Mohd. Mustafa Al Bakri Abdullah , Mohd Arif Anuar Mohd Salleh , Norsuria Mahmed , Azliza Azani , Chobpattana V.

There have been experiments on TiO2 thin films synthesized utilizing sol-gel techniques. The sol-gel method is a straightforward technology that gives numerous benefits to the researcher, for instance, material's reliability, reproducibility, and controllability. Following from there, it can be utilized to make high-quality nano-structured thin films. According to previous studies, the TiO2 films' characteristics occur to be highly dependent on the production parameters and initial materials utilized. Controlling the formation of TiO2 thin films with the sol-gel method was momentarily discussed here.

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Magnetic-Based Coreshell Nanoparticles as Potential Adsorbents for the Removal of Cu2+ under Ultraviolet (UV) Light

2021-11-12 , Husni H.N. , Norsuria Mahmed , Ge Y. , Mohd Natashah Norizan , Dewi Suriyani Che Halin , Kamrosni Abdul Razak , Ili Salwani Mohamad

The magnetite (Fe3O4) and maghemite (gFe2O3) nanoparticles, magnetite-silica-silver chloride (Fe3O4-SiO2-AgCl) and maghemite-silica-silver chloride (gFe2O3-SiO2-AgCl) coreshell structures have successfully been synthesized by using a simple wet chemistry method. The efficiency of these particles as the adsorbents for the removal of copper ion, Cu2+ in aqueous solution under UV light was investigated. Two different parameters were studied, namely the adsorbents contact time (60, 120, 180, 240 and 300s) and the solution-stirring rate (100, 200 and 300 rpm). From the results, the removal percentage of the copper ions from the solution were above 90% after 5 hours of adsorption process at 300 rpm by using Fe3O4 (94%) and gFe2O3 (92%) nanoparticles. The maximum removal of copper ions was nearly 100% when gFe2O3-SiO2-AgCl & Fe3O4-SiO2-AgCl coreshell particles were used. The samples that were prepared without magnetic core such as AgCl-SiO2, AgCl and SiO2 particles, showed lower percentage of the copper ions removal (78%, 60% and 20%, respectively). This situation shows that the magnetic nanoparticles plays and important role during the adsorption process due to their large active sites for the adsorption to occur.

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Self-cleaning property of ag/tio2 thin film

2020-01-01 , Kamrosni Abdul Razak , Dewi Suriyani Che Halin , Azliza Azani , Mohd. Mustafa Al Bakri Abdullah , Mohd Arif Anuar Mohd Salleh , Norsuria Mahmed , Chobpattana V.

Ag/TiO2 thin film was prepared by the sol-gel method through the hydrolysis of titanium tetraisopropoxide and silver nitrate solution. Spin coating method was used to get uniform film on ITO glass substrate followed by annealing process for 1 hour. After that, all the samples were characterised using GIXRD and FESEM and undergone water contact angle test and MB degradation. Silver ion concentrations were varied to observe the effect on crystalline state, morphology, wettability and photocatalytic properties. The results showed that Ag/TiO2 thin film was in anatase phase and it could degrade nearly 70% of methylene blue after 150 min illumination. The formed Ag/TiO2 thin film has excellent self-cleaning property with compact, continuous, smooth, and good hydrophilicity property.

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Synthesis of Zn/TiO2 Thin Films for Self-Cleaning Applications

2022-07-01 , Dewi Suriyani Che Halin , Abidin A.S.Z. , Azani A. , Mohd Arif Anuar Mohd Salleh , Kamrosni Abdul Razak , Mohd. Mustafa Al Bakri Abdullah , Muhammad Mahyiddin Ramli , Sandu A.V. , Vizureanu P. , Kaczmarek L. , Garus S. , Garus J.

Titanium dioxide (TiO2) thin film has been widely used in semiconductor applications. The surface modification on TiO2 has been done by adding zinc (Zn) in order to improve surface wettability and enhance the photocatalysis efficiency for solar cell applications. Self-cleaning technology is very important to sustain the efficiency of the solar cell and reduce the cost of the maintenance of the solar cell. In this work, the sol–gel method was used due to the economic factor and its best efficiency. The sol–gel method is a wet chemical technique involving several steps, such as hydrolysis and polycondensation, gelation, aging, drying, densification, and crystallization. The X-Ray diffraction pattern shows that anatase and rutile phases were detected at 2θ = 36.3864◦. It was clearly seen at 4% Zn-doped TiO2 annealed at 400◦C that due to the increment of Zn concentration, the phase transformed from the anatase phase to the rutile phase at high temperature. The scanning electron microscope micrograph shows that Zn concentration affects grain size. The water contact angle produced when 4% Zn-doped TiO2 was annealed at 300◦C, was 18◦ — higher than in the sample of 4% Zn-doped TiO2 annealed at 400◦C. These results clearly showed that the dopant concentration and the annealing temperature influence the properties of TiO2 for a self-cleaning application.

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Surface Modification of GO/TiO2 Thin Film by Sodium Dodecyl Sulphate for Photocatalytic Applications

2024-01-01 , Azliza Azani , Dewi Suriyani Che Halin , Vizureanu P. , Mohd Arif Anuar Mohd Salleh , Kamrosni Abdul Razak , Mohd. Mustafa Al Bakri Abdullah , Muhammad Mahyiddin Ramli , Mohd Fairul Sharin Abdul Razak , Sandu A.V. , Mohamad N.

Photocatalyst material titanium dioxide (TiO2) and graphene oxide (GO) were used to improve the self-cleaning properties of thin films. The sol–gel spin-coating method was successfully used to synthesize GO/TiO2 thin films. Surface modification was applied to optimize the self-cleaning capabilities by adding several concentrations of sodium dodecyl sulfate (SDS) (0.1 w/v%, 0.2 w/v%, 0.3 w/v%, 0.4 w/v%, and 0.5 w/v%) to the parent solution. The synthesized thin films were investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction, UV-visible spectroscopy, water contact angle analysis, and photocatalytic analysis. The AFM and SEM images revealed that as the SDS amount increased, the particles became less agglomerated, and the roughness of the surface reduced from 2.54 × 102 nm to 0.83 × 102 nm. The wettability analysis showed that when SDS increased to 0.4 w/v%, the water contact angle dropped to 15.30°, implying that the thin film exhibits hydrophilic qualities. A decrease in the GO/TiO2 band gap was obtained linearly with the increase in SDS addition from 3.17 eV to 2.75 eV. Finally, the improvement of the surface coating and reduction of the band gap enhanced the photocatalytic activity, which degraded 78.97% of methylene blue, which was obtained by 0.4SDS.