Kamrosni Abdul Razak
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Preferred name
Kamrosni Abdul Razak
Official Name
Razak, Kamrosni Abdul
Alternative Name
Abdul Razak, Kamrosni
Razak, K. Abdul
Razak, Kamrosni Ab
Razak, Kamrosni Abdul
Razak, K. A.
Abdul Razak, K.
K., Abdul Razak
Main Affiliation
Scopus Author ID
57207592874
Researcher ID
DNW-1117-2022

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Sintesis filem nipis AG/TIO₂ melalui kaedah sol-gel untuk aplikasi pembersihan diri

2019 , Kamrosni Abdul Razak

Titanium dioxide (TiO₂) thin film coating has attracted tremendous attention from many researchers due to its light absorption and photocatalytic properties, which make it suitable to be used for self-cleaning applications. In this research, the Ag/TiO₂ thin film was produced by using a simple and fast sol-gel spin coating method. By using a developed formulation, the Ag/TiO₂ thin film coating can be produced in 25 minutes of time. The preparation of the Ag/TiO₂ thin film coating can be divided into three different parameters. For the first parameter, the different concentration of AgNO₃ solution was used. The second parameter involved the different annealing temperatures, while the third parameter studied on the influence of polyethylene glycol (PEG) addition onto the formation of the thin film. The synthesized thin film coatings were characterized by using an X-ray diffraction (XRD), scanning electron microscope (SEM) and atomic force microscopy (AFM). The light absorption study was conducted by using a UV-visible (UV-Vis) spectroscopy. The wettability and photocatalytic testing were also conducted. From the results, the addition of 0.1 M of AgNO₃ solution had produced the Ag/TiO₂ thin film with smooth morphology and homogenously coated over the indium thin oxide (ITO) glass substrate. The optical property was enhanced where the light absorption was extended into the visible light range with reducing the energy level from 3.30 eV to 3.10 eV, compared to the TiO₂ thin film that was produced without the addition of AgNO₃. The film also had the lowest water contact angle and exhibited the best self-cleaning behavior with highest decomposition of the methylene blue solution, which is almost 60%. In term of annealing temperature, the optimum temperature for obtaining an anatase (TiO₂) structure with small particles size and homogenous surface morphology was 500 ⁰C. The film light absorption was found to be the highest with lowest energy level, 3.10 eV. The film that was annealed at 500 ⁰C also showed the lowest water contact angle, which is 11.30o and the best self-cleaning properties where more than 70% of the methylene blue solution can be decomposed in 150 minutes. The addition of 0.15 g of PEG resulted in small, homogenous porous structure with 19.6 nm of the particle size. The film had a good absorption in the visible light range with energy level of 2.65 eV and had almost 80% of photocatalytic decomposition of methylene blue in 150 minutes. From this research, it can be concluded that the 0.1 M of AgNO₃ concentration, 500oC of annealing temperature and 0.15 g of PEG became an optimum parameter in producing a good self-cleaning Ag/TiO₂ thin film. It was also found that the produced Ag/TiO₂ thin film had a good optical and photocatalytic behavior and suitable to be used in self-cleaning applications.

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Microstructure evolution of Ag/TiO₂ thin film

2021 , Dewi Suriyani Che Halin , Kamrosni Abdul Razak , Mohd Arif Anuar Mohd Salleh , Mohd Izrul Izwan Ramli , Mohd. Mustafa Al Bakri Abdullah , Ayu Wazira Azhari , Kazuhiro Nogita , Hideyuki Yasuda , Marcin Nabiałek , Jerzy J. Wysłocki

Ag/TiO₂ thin films were prepared using the sol-gel spin coating method. The microstructural growth behaviors of the prepared Ag/TiO₂ thin films were elucidated using real-time synchrotron radiation imaging, its structure was determined using grazing incidence X-ray diffraction (GIXRD), its morphology was imaged using the field emission scanning electron microscopy (FESEM), and its surface topography was examined using the atomic force microscope (AFM) in contact mode. The cubical shape was detected and identified as Ag, while the anatase, TiO₂ thin film resembled a porous ring-like structure. It was found that each ring that coalesced and formed channels occurred at a low annealing temperature of 280 °C. The energy dispersive X-ray (EDX) result revealed a small amount of Ag presence in the Ag/TiO₂ thin films. From the in-situ synchrotron radiation imaging, it was observed that as the annealing time increased, the growth of Ag/TiO₂ also increased in terms of area and the number of junctions. The growth rate of Ag/TiO₂ at 600 s was 47.26 µm2/s, and after 1200 s it decreased to 11.50 µm2/s and 11.55 µm2/s at 1800 s. Prolonged annealing will further decrease the growth rate to 5.94 µm2/s, 4.12 µm2/s and 4.86 µm2/s at 2400 s, 3000 s and 3600 s, respectively.

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The effect of polyethylene glycol addition on wettability and optical properties of go/tio2 thin film

2021-08-02 , Azliza Azani , Dewi Suriyani Che Halin , Kamrosni Abdul Razak , Mohd. Mustafa Al Bakri Abdullah , Nabiałek M. , Ramli M.M. , Razak M.F.S.A. , Sandu A.V. , Sochacki W. , Skrzypczak T.

Modification has been made to TiO2 thin film to improve the wettability and the absorption of light. The sol‐gel spin coating method was successfully used to synthesize GO/TiO2 thin films using a titanium (IV) isopropoxide (TTIP) as a precursor. Different amounts of polyethylene glycol (PEG) (20 to 100 mg) were added into the parent sol solution to improve the optical properties and wettability of the GO/TiO2 thin film. The effect of different amounts of PEG was characterized using X‐ray diffraction (XRD) for the phase composition, scanning electron microscopy (SEM) for micro-structure observation, atomic force microscopy (AFM) for the surface topography, ultraviolet–visi-ble spectrophotometry (UV‐VIS) for the optical properties and wettability of the thin films by meas-uring the water contact angle. The XRD analysis showed the amorphous phase. The SEM and AFM images revealed that the particles were less agglomerated and surface roughness increases from 1.21 × 102 to 2.63 × 102 nm when the amount of PEG increased. The wettability analysis results show that the water contact angle of the thin film decreased to 27.52° with the increase of PEG to 80 mg which indicated that the thin film has hydrophilic properties. The optical properties also improved significantly, where the light absorbance wavelength became wider and the band gap was reduced from 3.31 to 2.82 eV with the presence of PEG.

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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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Fabrikasi dan penganodan komposit metalurgi serbuk aluminium-magnesium diperkuat gentian pendek alumina saffil

2013 , Kamrosni Abdul Razak

Anodising process on powder metallurgy aluminium-magnesium composites reinforced with short fibre alumina SaffilTM has been studied. PM Al-Mg composites were fabricated using PM route with Mg powder as the alloying element and short fibre alumina SaffilTM as the reinforcements. Mg powder was added in the rate of 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 wt% and short fibre alumina SaffilTM 5, 10, 15, 20 and 25 wt% to study the effect of adding those elements in various compositions. Microstructure analysis, density and porosity test and hardness test was used to determine the optimum weight percent of Mg powder and short fibre alumina SaffilTM in the PM Al-Mg composites. Result showed that 2.0 wt% of Mg is the best composition according to the surface morphology of the PM Al-Mg alloy with the least porosity. Meanwhile, the density and hardness recorded the highest value with this composition, 2.3 g/cm3 and 37.1 HVN accordingly. The optimum composition for short fibre alumina SaffilTM is 10% according to the density of 2.25 g/cm3, hardness value of 48 HVN, and had the most homogenous fibre distribution compared to the other compositions. After that, PM Al-Mg composite samples were coated in sulphuric acid anodising process. The study focused on effect of the various anodising voltage (10V, 12V, 14V, 16V and 18V) in 15% sulphuric acid and various concentration of sulphuric acid (5%, 10%, 15%, 20% and 25%) on the growth of a good anodising coating film. The anodising process were done in the room temperature (+25oC) for 60 minutes. The increasing of the coating film mass were recorded every 10 minutes for each anodising parameters. Cross sectional morphology was used to analyse the anodising coating film thickness formed on the surface of PM Al-Mg composites. The increasing of anodising voltage and concentration of sulphuric acid resulted on the increasing of anodising coating film. From the result, the most suitable anodising voltage is 16V and 15% concentration of sulphuric acid according to the coating film formed is uniform, less of porosity and showed the best rate of coating film mass. The maximum hardness value was also shown by anodising with 16V voltage (63HVN) and 15% concentration of sulphuric acid (64 HVN). After the anodising process, PM Al-Mg composite samples were tested in electrochemical testing in 3.5% NaCl solution to study the effect of various parameters of anodising coating on corrosion resistance. Tafel analysis showed that the corrosion rate was decreased and corrosion resistance was increased after the anodising coating process on PM Al-Mg composites. The minimum corrosion rate and maximum corrosion resistance were recorded by anodising with 16V voltage and 15% concentration of sulphuric acid, same goes to the best parameters of anodising. A good anodising coating can decrease the corrosion rate and increase the corrosion resistance of PM Al-Mg composite samples.

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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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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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Effect of temperature and amount of Ag on TiO₂ thin film synthesised via sol–gel method

2025-02 , Dewi Suriyani Che Halin , Kamrosni Abdul Razak , Dharshini Karikalan , Lukasz Kaczmarek , Sebastian Miszczak , Ayu Wazira Azhari , Mohd Arif Anuar Mohd Salleh , Nur Izzati Muhammad Nadzri , Juyana A. Wahab , Mohd. Mustafa Al Bakri Abdullah

TiO₂ sol was produced via the sol–gel method with different amounts of AgNO₃ as the source of Ag. The Ag/TiO₂ thin film was obtained by spin coating and was annealed at various annealing temperatures (300°C, 400°C and 500°C) for 1 h. The effect of different amounts of AgNO₃ and different annealing temperatures on the TiO₂ thin films was studied by characterising the phase composition, surface morphology and water contact angle. Results from the x-ray diffraction (XRD) pattern show that with the addition of AgNO₃, Ag/TiO₂ can be formed at low annealing temperatures (300°C). At increased annealing temperatures (400°C and 500°C) and amounts of AgNO₃ (1.0 ml and 1.5 ml), Ag₂O and Ag₃O4 phases were observed. Flakes or flaky islands were formed on the thin film due to thermal expansion mismatch between the film and substrate, residual stress within the film or the release of volatile species when annealed at a low temperature of ⁓300°C. Increasing the temperature to 500°C resulted in the growth and coalescence of the flaky islands by the surface diffusion of adsorbed atoms (adatoms) and their annexation to the surface of existing nuclei. The water contact angle provides valuable insight into the surface interactions between water droplets and the surface of Ag/TiO₂ thin films. It was found that at 1.5 ml AgNO₃, the increased annealing temperature from 300°C to 500°C decreased the water contact angle of Ag/TiO₂ thin films from 83.86° to 34.62°, forming superhydrophilic properties, which indicated its excellent potential as a photocatalyst.

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Recent advances in synthesis of graphite from agricultural bio-waste material: a review

2023 , Yee Wen Yap , Norsuria Mahmed , Mohd Natashah Norizan , Shayfull Zamree Abd. Rahim , Midhat Nabil Ahmad Salimi , Kamrosni Abdul Razak , Ili Salwani Mohamad , Mohd. Mustafa Al Bakri Abdullah

Graphitic carbon is a valuable material that can be utilized in many fields, such as electronics, energy storage and wastewater filtration. Due to the high demand for commercial graphite, an alternative raw material with lower costs that is environmentally friendly has been explored. Amongst these, an agricultural bio-waste material has become an option due to its highly bioactive properties, such as bioavailability, antioxidant, antimicrobial, in vitro and anti-inflammatory properties. In addition, biomass wastes usually have high organic carbon content, which has been discovered by many researchers as an alternative carbon material to produce graphite. However, there are several challenges associated with the graphite production process from biomass waste materials, such as impurities, the processing conditions and production costs. Agricultural bio-waste materials typically contain many volatiles and impurities, which can interfere with the synthesis process and reduce the quality of the graphitic carbon produced. Moreover, the processing conditions required for the synthesis of graphitic carbon from agricultural biomass waste materials are quite challenging to optimize. The temperature, pressure, catalyst used and other parameters must be carefully controlled to ensure that the desired product is obtained. Nevertheless, the use of agricultural biomass waste materials as a raw material for graphitic carbon synthesis can reduce the production costs. Improving the overall cost-effectiveness of this approach depends on many factors, including the availability and cost of the feedstock, the processing costs and the market demand for the final product. Therefore, in this review, the importance of biomass waste utilization is discussed. Various methods of synthesizing graphitic carbon are also reviewed. The discussion ranges from the conversion of biomass waste into carbon-rich feedstocks with different recent advances to the method of synthesis of graphitic carbon. The importance of utilizing agricultural biomass waste and the types of potential biomass waste carbon precursors and their pre-treatment methods are also reviewed. Finally, the gaps found in the previous research are proposed as a future research suggestion. Overall, the synthesis of graphite from agricultural bio-waste materials is a promising area of research, but more work is needed to address the challenges associated with this process and to demonstrate its viability at scale.

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Microstructural Study on Ag/TiO2 Thin Film

2022-07-01 , Kamrosni Abdul Razak , Dewi Suriyani Che Halin , Azliza Azani , Mohd. Mustafa Al Bakri Abdullah , Mohd Arif Anuar Mohd Salleh , Norsuria Mahmed , Chobpattana V. , Kaczmarek L. , Sandu A.V. , Garus S.

The synthesis of Ag/TiO2 thin film was carried out by the sol–gel spin coating method using ITO glass as a substrate in a short period of stirring time, which is less than 25 min. The produced films were annealed in a furnace at 500◦C for 1 h. Various concentrations of AgNO3, from 0.1 to 0.9 M, were added. The as-prepared films were characterized using X-ray diffraction, scanning electron microscopy, and atomic force microscopy. The results indicate that all films showed a single phase of anatase, TiO2. Ag/TiO2 thin films with 0.1 M of AgNO3 solution show that the elements form networks connecting Ag/TiO2 microstructures forming a porous, consistent, and continuous layer on the substrate surface.

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