Ayu Wazira Azhari
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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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  • Publication
    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.
  • Publication
    A Study on the Environmental Impact During Distribution and Disposal Stages for the 3-Ply Face Masks by Using Life Cycle Assessment (LCA)
    ( 2022-01-01)
    Chow Suet Mun Christine
    ;
    Tengku Nuraiti Tengku Izhar
    ;
    Irnis Azura Zakaria
    ;
    Sara Yasina Yusuf
    ;
    Ayu Wazira Azhari
    ;
    Boboc M.
    The demand of face masks had increased tremendously due to pandemic outbreak of COVID-19, leading to the increment production rate of face masks in Malaysia. Waste is also produced at the same time, resulting impacts towards the environment. Due to the land scarcity issue in Malaysia, the end of life treatment for the waste is taken into consideration. The study tools used in this study is life cycle assessment (LCA) to identify the significant potential environmental impact produced during the life cycle stages for distribution and disposal through GaBi Education Software. The disposal stage between landfill and incineration of the 3-Ply face masks is studied to determine the end of life treatment for it. The impact assessment method selected in this study is CML 2001-Jan 2016 with the environmental indicator of Global Warming Potential (GWP), Acidification Potential (AP), Eutrophication Potential (EP) and Ozone Depletion Potential (ODP). GWP results in producing highest impact to the environment during both distribution and disposal stages. The impact of GWP also relates to the climate change. Modern incineration is recommended to overcome the issue of land scarcity in Malaysia as the amount of waste by 3-Ply face masks are increasing due to the pandemic COVID-19, reducing the impacts towards the environment.
  • Publication
    Exploring the potential of metal oxides as cathodic catalysts in a double chambered microbial fuel cell for phenol removal and power generation
    ( 2023-07-01)
    Yap K.L.
    ;
    Ho Li Ngee
    ;
    Guo K.
    ;
    Liew Yun Ming
    ;
    Nabilah Aminah Lutpi
    ;
    Ayu Wazira Azhari
    ;
    Thor S.H.
    ;
    Teoh T.P.
    ;
    Oon Y.S.
    ;
    Ong Soon An
    Detection of high phenol concentrations in industrial wastewater contributed to the need for more efficient wastewater treatment approaches. This study compared and investigated the different metal oxides as cathodic catalysts in a double chambered microbial fuel cell (MFC) for simultaneous phenol removal and bioelectricity generation. Metal oxides such as copper (II) oxide (CuO), manganese dioxide (MnO2) and tin (IV) oxide (SnO2) were synthesized and loaded on a carbon (C) plate, respectively, for application as cathode in the MFC. Results revealed that total chemical oxygen demand and phenol removal efficiency of MFC depleted in the order of CuO/C (96.69 and 100 %) > β-MnO2/C (90.93 and 94.41 %) > α-MnO2/C (84.69 and 90.17 %) > SnO2/C (80.25 and 84.84 %) > bare C (70.48 and 77.06 %) cathode due to the deterioration in the oxygen reduction reaction reactivity. Besides, the solution pH was crucial in determining the catalyst's surface charge properties. At pH 8, higher solution conductivity and stronger electrostatic attraction between positively charged CuO and anionic phenol molecules were favourable for the complete phenol removal. This phenomenon contributed to a 1.77-fold higher maximum power density attained at pH 8 (29.24 mW m−2) than that of pH 11 (16.52 mW m−2) due to more electrons could be utilized for electricity generation. This study provided valuable information on the facile fabrication of cost-effective cathodic catalysts in a double chambered MFC for wastewater treatment and bioelectricity generation.
      1
  • Publication
    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
    ;
    Sopian, K.
    ;
    Uda Hashim
    ;
    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.
  • Publication
    Effect of graphene oxide on microstructure and optical properties of TiO2 thin film
    ( 2019-01-01)
    Azani A.
    ;
    Dewi Suriyani Che Halin
    ;
    Razak K.A.
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Mohd Salleh M.A.A.
    ;
    Abdul Razak M.F.S.
    ;
    Norsuria Mahmed
    ;
    Ramli M.M.
    ;
    Ayu Wazira Azhari
    ;
    Chobpattana V.
    GO/TiO2 thin films have been synthesized from titanium (IV) isopropoxide (TTIP) by a sol-gel method. The films were deposited onto a glass substrate using spin coating deposition technique then were subjected to annealed process at 350 °C. The different amount of graphene oxide (GO) was added into the parent solution of sol in order to investigate the microstructure, topography, optical band gap and photocatalytic activity of the thin films. The prepared thin films were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), UV-VIS spectrophotometry and degradation of methylene blue (MB). AFM images reveal a rougher surface of GO/TiO2 thin film than bare TiO2 thin film due to GO particles. Moreover, the SEM images showed the formation of semispherical microstructure of bare TiO2 changes to some larger combined molecules with GO addition. The UV-Vis spectrophotometer results show that with optical direct energy gap decreases from 3.30 to 3.18 eV after GO addition due to the effect of high surface roughness and bigger grain size. Furthermore, the optical results also indicated that GO improved the optical properties of TiO2 in the visible range region.
  • Publication
    Annealing Effects on Polycrystalline Silicon Germanium (SiGe) Thin Films grown on Nanostructured Silicon Substrates using Thermal Evaporation Technique
    ( 2022-10-01)
    Ayu Wazira Azhari
    ;
    Eop T.S.
    ;
    Dewi Suriyani Che Halin
    ;
    Sopian K.
    ;
    Uda Hashim
    ;
    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.
  • Publication
    Isu pemanasan global
    ( 2012)
    Norazian Mohamed Noor
    ;
    Noridah Yangman
    ;
    Ain Nihla Kamarudzaman
    ;
    Ayu Wazira Azhari
    ;
    Nabilah Aminah Lutpi
    ;
    Kamarudin Hussin
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Abdul Haqi Ibrahim
    Panasnya 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
      46  644
  • Publication
    Microplastics in facial cleanser: extraction, identification, potential toxicity, and continuous-flow removal using agricultural waste–based biochar
    ( 2023-05-01)
    Hanif M.A.
    ;
    Naimah Ibrahim
    ;
    Farrah Aini Dahalan
    ;
    Umi Fazara Md Ali
    ;
    Masitah Hasan
    ;
    Ayu Wazira Azhari
    ;
    Jalil A.A.
    Microplastic (MP) is an emerging contaminant of concern due to its ubiquitous quantity in the environment, small size, and potential toxicity due to strong affinity towards other contaminants. In this work, MP particles (5–300 μm) were extracted from a commercial facial cleanser and determined to be irregular polyethylene (PE) microbeads based on characterization with field emission scanning electron microscopy (FESEM) and Raman spectroscopy. The potential of extracted MP acting as toxic pollutants’ vector was analyzed via adsorption of methylene blue and methyl orange dye where significant dye uptake was observed. Synthetic wastewater containing the extracted MP was subjected to a continuous-flow column study using palm kernel shell and coconut shell biochar as the filter/adsorbent media. The prepared biochar was characterized via proximate and ultimate analysis, FESEM, contact angle measurement, atomic force microscopy (AFM), and Fourier transform infrared (FTIR) spectroscopy to investigate the role of the biochar properties in MP removal. MP removal performance was determined by measuring the turbidity and weighing the dry mass of particles remaining in the effluent following treatment. Promising results were obtained from the study with highest removal of MP (96.65%) attained through palm kernel shell biochar with particle size of 0.6–1.18 mm and continuous-flow column size of 20 mm. Graphical abstract: [Figure not available: see fulltext.].
      1
  • Publication
    Synthesis of Ag-TiO2thin film - Molarity and temperature effect on Microstructure
    ( 2020-08-01)
    Dewi Suriyani Che Halin
    ;
    Razak K.A.
    ;
    Azani A.
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Mohd Arif Anuar Mohd Salleh
    ;
    Mahmed N.
    ;
    Ramli M.M.
    ;
    Ayu Wazira Azhari
    ;
    Chobpattana V.
    ;
    Kaczmarek
    Ag-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.
      2
  • Publication
    Progress in tin-germanium perovskite solar cells: A review
    ( 2023-11-01)
    Azizman M.S.A.
    ;
    Ayu Wazira Azhari
    ;
    Dewi Suriyani Che Halin
    ;
    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.
      2  2