Dewi Suriyani Che Halin
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Preferred name
Dewi Suriyani Che Halin
Official Name
Halin, Dewi Suriyani Che
Alternative Name
Che Halin, Dewi Suriyani
Che Halin, D. S.
Suriyani Che Halin, Dewi
Halin, Dewi Suriyani Che
Halin, D. S.Che
Halin, D. S.C.
D. S., Che Halin
Main Affiliation
Scopus Author ID
36158106300
Researcher ID
AAC-9478-2019

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Annealing effects on Polycrystalline Silicon Germanium (SiGe) thin films grown on nanostructured silicon substrates using thermal evaporation technique

2022-10 , Ayu Wazira Azhari , Eop, T. S. , Dewi Suriyani Che Halin , Uda Hashim , Sopian, K. , Zaidi, S. H.

Polycrystalline SiGe thin films have been formed after thermal annealing of formerly vacuum evaporated a-Ge layers. The a-Ge thin films were deposited onto nanostructured Si substrates via low-cost thermal evaporation method. Then, the films were annealed in a furnace at temperatures ranging from 400 °C to 1000 °C resulting in crystal growth of the SiGe layers. In general, the annealing temperature for polycrystalline SiGe is between 600 °C – 800 °C. The crystalline structure of the SiGe layer is improved as a function of increased temperature. This is shown by the low FWHM of about 5.27 as compared to the commercially available Ge substrates where the FWHM value is about 5.06. This method also produces more relax Ge layer where the strain value is 0.261.

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Enhancement of Power Conversion Efficiency with Zinc Oxide as Photoanode and Cyanococcus, Punica granatum L., and Vitis vinifera as Natural Fruit Dyes for Dye-Sensitized Solar Cells

2022-11-01 , Ili Salwani Mohamad , Mohd Natashah Norizan , Norsuria Mahmed , Jamalullail N. , Dewi Suriyani Che Halin , Mohd Arif Anuar Mohd Salleh , Sandu A.V. , Baltatu M.S. , Vizureanu P.

Ruthenium N719 is a well-known material used as the dye in commercial dye-sensitized solar cell (DSSC) devices. However, it poses risks to human health and the environment over time. On the other hand, titanium dioxide (TiO2) has low electron mobility and high recombination losses when used as a photoanode in this photovoltaic technology device. In addition, using Ruthenium as the dye material harms the environment and human health. As an alternative sensitizer to compensate Ruthenium on two different photoanodes (TiO2 and ZnO), we constructed DSSC devices in this study using three different natural dyes (blueberry, pomegranate, and black grape). In good agreement with the anthocyanin content in the fruits, black grape, with the highest anthocyanin content (450.3 mg/L) compared to other fruit dyes (blueberry—386.6 mg/L and pomegranate—450.3 mg/L), resulted in the highest energy conversion efficiency (3.63%) for the natural dye-based DSSC. Furthermore, this research proved that the electrical performance of natural dye sensitizer in DSSC applications with a ZnO photoanode is better than using hazardous Ru N719 dye with a TiO2 photoanode owing to the advantage of high electron mobility in ZnO.

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Interdigitated electrodes as impedance and capacitance biosensors: A review

2017-09-26 , Mazlan N. , Muhammad Mahyiddin Ramli , Mohd. Mustafa Al Bakri Abdullah , Dewi Suriyani Che Halin , Isa S. , Talip L. , Nuaim Siddiqi Danial , Sohiful Anuar Zainol Murad

Interdigitated electrodes (IDEs) are made of two individually addressable interdigitated comb-like electrode structures. IDEs are one of the most favored transducers, widely utilized in technological applications especially in the field of biological and chemical sensors due to their inexpensive, ease of fabrication process and high sensitivity. In order to detect and analyze a biochemical molecule or analyte, the impedance and capacitance signal need to be obtained. This paper investigates the working principle and influencer of the impedance and capacitance biosensors. The impedance biosensor depends on the resistance and capacitance while the capacitance biosensor influenced by the dielectric permittivity. However, the geometry and structures of the interdigitated electrodes affect both impedance and capacitance biosensor. The details have been discussed in this paper.

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Microstructural studies of ag/tio2 thin film; effect of annealing temperature

2022-01-01 , Kamrosni A.R. , Dewi Suriyani Che Halin , Azliza A. , Mohd. Mustafa Al Bakri Abdullah , Mohd Arif Anuar Mohd Salleh , Norsuria Mahmed , Chobpattana V. , Kaczmarek L. , Jez B. , Nabialek M.

Microstructures are an important link between materials processing and performance, and microstructure control is essential for any materials processing route where the microstructure plays a major role in determining the properties. In this work, silverdoped titanium dioxide (Ag/TiO2) thin film was prepared by the sol-gel method through the hydrolysis of titanium tetra-isopropoxide and silver nitrate solution. The sol was spin coated on ITO glass substrate to get uniform film followed by annealing process for 2 hours. The obtained films were annealed at different annealing temperatures in the range of 300°C-600°C in order to observe the effect on crystalline state, microstructures and optical properties of Ag/TiO2thin film. The thin films were characterized by X-Ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectrophotometry. It is clearly seen, when the annealing temperature increases to 500°C, a peak at 2θ = 25.30° can be seen which refers to the structure of TiO2tetragonal anatase. The structure of Ag/TiO2thin film become denser, linked together, porous and uniformly distributed on the surface and displays the highest cut-off wavelength value which is 396 nm with the lowest band gap value, which is 3.10 eV.

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Tensile and dielectric properties of Tin Dioxide reinforced deproteinized natural rubber nanocomposites for electrical insulator

2023-07 , Noraiham Mohamad , Hairul Effendy Ab Maulod , Jeefferie Abd Razak , Mohd Sharin Ghani , Nor Hidayah Rahim , Mohd Hanafiah Mohd Isa , Dewi Suriyani Che Halin , Mohammed Iqbal Shueb , Norshafarina Ismail

Tin dioxide, SnO2 nanoparticles combined with deproteinized natural rubber could be an effective electrical insulator that inherits its parents’ insulation and conductivity. The deproteinized natural rubber (DPNR) nanocomposites containing uncalcined SnO2 nanofillers at 0.5, 1.0, 3.0, and 7.0 phr were investigated for tensile and dielectric properties. The nanocomposites were prepared using a Haake internal mixer through a melt compounding method and vulcanized by a semi-EV system. Their properties were explored and compared with the DPNR vulcanizate. The highest tensile strength of about 28 MPa was obtained at 3.0 phr SnO2 loading. The elongation at break increases with the increase of nanofiller loading up to 3 phr and then decreases. With a rise in SnO2, the dielectric constant decreased but increased once 7 phr SnO2 was added. The nanocomposites exhibited the minimum dielectric constant at the optimum SnO2 loading of 3.0 phr. Therefore, the SnO2-reinforced DPNR nanocomposites are promising to be further explored for a stretchable electric insulator material.

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Thermal behaviour and microstructural analysis of Sn-40Pb alloy and Sn-40Pb soldered on electroless nickel/immersion gold

2020 , Ai Ling Teoh , Mohd Arif Anuar Mohd Salleh , Dewi Suriyani Che Halin , Foo Kai Loong

Due to the toxicity of lead solder, the lead-free solder has been developing and improved in order to replace the lead solder. However, the behaviour and properties of lead solder is still better than the lead-free solder, especially in application when soldering on substrate. Hence, a common lead solder, Sn-40Pb is studied in this research by comparing with Sn-40Pb soldering on electroless nickel/immersion gold (ENIG) substrate. The thermal behaviour by differential scanning calorimeter (DSC) and microstructure formation with elemental analysis by scanning electron microscope (SEM) were carried out for Sn-40Pb solder alloy and Sn-40Pb soldered on ENIG substrate in this study. The result showed that the pasty range of Sn-40Pb was lower than Sn-40Pb/ENIG while the undercooling was higher. The diffusion and dissolution of Ni and Cu elements from ENIG substrate into the solder, forming the lead-rich phase with Ni elements and interfacial (Cu,Ni)6Sn5 with Pb elements in Sn-40Pb/ENIG. The diffusion and dissolution of elements from substrate into the solder affects the thermal behaviour and microstructural of solder.

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

2022-01-24 , Abdul Razak K. , Dewi Suriyani Che Halin , Mohd. Mustafa Al Bakri Abdullah , Mohd Arif Anuar Mohd Salleh , Mahmed N. , Azani A. , 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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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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