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Ayu Wazira Azhari
Preferred name
Ayu Wazira Azhari
Official Name
Ayu Wazira, Azhari
Alternative Name
Ayu, A. W.
Azhari, Ayu W.
Main Affiliation
Scopus Author ID
24450001400
Researcher ID
ABA-7808-2020
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1 - 9 of 9
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PublicationIsu pemanasan global( 2012)
;Noridah Yangman ;Ain Nihla KamarudzamanPanasnya hari ini! Pernahkan anda mendengar rungutan atau keluhan seperti ini keluar daripada mulut masyarakat sekitar anda? Atau anda sendiri pernah mengalami hal ini. Anda tidak salah, data-data yang ada memang menunjukkan bumi kita mengalami peningkatan suhu yang amat merisaukan sejak akhir-akhir ini. Hal ini berkait langsung dengan isu global yang kebelakangan ini makin hangat diperkatakan oleh masyarakat dunia iaitu pemanasan global. Ironinya, kesedaran mengenai hal ini dalam kalangan masyarakat amat kurang dan tidak hairan ada dalam kalangan masyarakat, langsung tidak tahu mengenai pemanasan global. Buku ini direalisasikan untuk memberi pengetahuan kepada pembacanya mengenai pemanasan global, punca pemanasan global, kesan-kesannya serta langkah-langkah pencegahan yang perlu dimainkan oleh semua pihak. Buku ini turut membincangkan pelaksanaan Protokol Montreal dan Protokol Kyoto dalam menangani masalah pemanasan global -
PublicationMicrostructure evolution of Ag/TiO2 thin film( 2021)
;Mohd Izrul Izwan Ramli ;Kazuhiro Nogita ;Hideyuki Yasuda ;Marcin NabiałekJerzy J. WysłockiAg/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. -
PublicationAnnealing effects on polycrystalline silicon germanium (SiGe) thin films grown on nanostructured silicon substrates using thermal evaporation technique( 2022-10)
;Eop, T. S. ;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. -
PublicationMicrostructure evolution of Ag/TiOâ‚‚ thin film( 2021)
;Mohd Izrul Izwan Ramli ;Kazuhiro Nogita ;Hideyuki Yasuda ;Marcin NabiałekJerzy J. WysłockiAg/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. -
PublicationNumerical simulation of lead-free tin and germanium based all perovskite tandem solar cell( 2023-12)
;Rae-Ann Lim Jia En ;Suhaila SepeaiNorasikin Ahmad LudinThe ability to customize the materials bandgaps makes perovskite solar cells a promising candidate for hybrid-tandem applications. This allows them to effectively utilize parts of the solar spectrum that silicon-based solar cells cannot efficiently capture, resulting in higher absorption coefficients. However, there is a lack of research on lead-free all-perovskite tandem solar cells, and secondary data on materials is limited. One of the main challenges in previous studies is the high cost and solid structure of traditional silicon-based solar cells, which require significant storage space. Additionally, lead-based perovskite solar cells pose environmental concerns due to their water solubility and potential harmful effects upon consumption. To address these issues, thin-film perovskite solar cells with liquid solvents are employed in the solar cell design. Lead is replaced with germanium and tin-based perovskites, which exhibit comparable photovoltaic performance to silicon. In the present work, the OghmaNano simulation tool was utilized to conduct numerical simulation of the perovskite design. The perovskite solar cell layers were structured as follows: FTO/ZnO/MAGeI3/Spiro-OMeTAD/FAMASnGeI3/Cu2O/Au. The variables considered included optimum layer thicknesses and bandgaps, as well as the most suitable materials for the ETL and HTL, aiming to obtain the highest efficiency. Based on the simulation results, the proposed perovskite structure shows remarkable photovoltaic parameters. The Voc was measured at 0.84 V Jsc of 16.1 mA/cm2, FF of 0.825, and PCE that reached 11.12%. This project contributes to future research on materials for the ETL and HTL of lead-free, tin and germanium based APTSCs. -
PublicationThe Effect of Polyethylene Glycol (PEG) on TiO2 Thin Films via Sol-Gel Method( 2020-03-18)
;Razak K.A. ;Mohamad Sukeri N.S. ;Azani A. ;Mahmed N. ;Ramli M.M.Chobpattana V.This research focus on the effect of polyethylene glycol (PEG) on TiO2 thin film. Sol-gel method is the best method which tends to be used due to its simplicity, good chemical homogeinity and high purity of the product. Titanium (IV) isopropoxide, isopropanol and acetic acid are the three different chemical which being used to make sol solution. The samples was then will annealed at three different temperature which are 400 °C, 500 °C and 600 °C to observed the phase composition of TiO2 added PEG thin film and pure TiO2 by using X-ray diffraction (XRD) analysis and the structural surface by using scanning electron microscope (SEM) analysis. The XRD analysis show the anatase phase present for the sample of pure TiO2 thin film and rutile phase present for the sample of TiO2 added PEG thin film. The micrograph of SEM show that with the addition of PEG at high temperature will give the analysis of flaky large cracked which is not separated to each other on the surface coating. Meanwhile, pure TiO2 give the result of irregular shape structure of the film. -
PublicationSynthesis of Ag-TiO2thin film - Molarity and temperature effect on Microstructure( 2020-08-01)
;Razak K.A. ;Azani A. ;Mahmed N. ;Ramli M.M. ;Chobpattana V.KaczmarekAg-TiO2thin films with different concentration of silver (Ag) added were successfully deposited onto Si-substrate via sol-gel spin coating method. The phase analysis and microstructures of Ag-TiO2thin films have been characterized by X-ray diffractometer and scanning electron microscope. X-ray diffraction spectra show existing different phases influenced by the concentration of the Ag and the annealing temperature. The micrograph of scanning electron microscopy revealed the thin films annealed at 600 °C with 7 mol% of Ag concentration which shows that the Ag particles were found like a white dot formed on the grain of TiO2thin films. -
PublicationMicrostructure evolution of ag/tio2 thin film( 2021-01-01)
;Mohd Izrul Izwan Ramli ;Nogita K. ;Yasuda H. ;Nabiałek M.Wysłocki J.J.Ag/TiO2 thin films were prepared using the sol-gel spin coating method. The microstruc-tural growth behaviors of the prepared Ag/TiO2 thin films were elucidated using real-time syn-chrotron 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. -
PublicationProgress in tin-germanium perovskite solar cells: A review( 2023-11-01)
;Azizman M.S.A. ;Ibrahim N. ;Sepeai S. ;Ludin N.A. ;Nor M.N.M.Ho L.N.The primary cause for concern in developing perovskite solar cells (PSCs) is the potential environmental repercussions of employing lead (Pb) as the absorber. The majority of studies hypothesised that the use of tin-based perovskite could be the key to creating environmentally and financially viable PSCs. This is because tin (Sn) and lead (Pb) are both elements in group 14 of the periodic table. Perovskite materials based on tin and lead also have nearly ideal direct band gaps, which range from 1.23 eV to 1.30 eV. Nonetheless, major challenges that may suppress the potential of Sn-based PSCs include the stability issue with low formation energy, high carrier density, and easily oxidised from Sn2+ to Sn4+ upon exposure to air. These limitations are anticipated to be vital impediments to creating a stable and effective Sn-based perovskite. Recent advances have shown that alloying with germanium (Ge) is one of the approaches to overcome stability issues and thus improve the overall efficiency of the PSCs. However, the stability and efficiency of these Ge-based PSCs are still unable to surpass those of Pb-based devices. This review covers the research interest in SnGe PSCs from the initial study to the current year by focusing on the methodology used and significant results. The output is believed to be useful in developing Pb-free PSCs using SnGe-based materials.