Norsuria Mahmed
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Preferred name
Norsuria Mahmed
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Norsuria, Mahmed
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Mahmed, Norsuria
Mahmed, N.
Norsuria, Mahmed
Norsuria, M.
Main Affiliation
Scopus Author ID
24802694300
Researcher ID
FOC-8505-2022

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Charge recombination in zinc oxide-based dye-sensitized solar cell: a mini review

2021-12 , Kaiswariah Magiswaran , Mohd Natashah Norizan , Ili Salwani Mohamad , Norsuria Mahmed , Siti Norhafizah Idris , Sharizal Ahmad Sobri

Dye-sensitized solar cell (DSSC) has been studied widely due to its efficiency and the simplicity of manufacturing technology. Much research has been performed to improve the photovoltaic output parameters in DSSC by modifying the photoanode layers. The efforts to investigate DSSC mainly focus on how to increase light absorption, speed electron transport in circuits, and reduce charge recombination. This review discusses the process of charge recombination and the paths of occurrence in a DSSC. Recombination occurs when the electrons in the conduction band fall into the valance band holes and is considered an unnecessary process in DSSC. Due to the recombination process, the photocurrent and the photovoltage are reduced, leading to lower power conversion efficiency. Hence, the ways to overcome the charge recombination process were also discussed.

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A Comprehensive Review of Midrange Wireless Power Transfer Using Dielectric Resonators

2021-01-01 , Azuwa Ali , Mohd Najib Mohd Yasin , Faiz Wan Ali W.F. , Norsuria Mahmed , Kamarudin M.R. , Ismahayati Adam , Muzammil Jusoh , Hasliza A Rahim @ Samsuddin , Khor Shing Fhan , Nurulazlina Ramli , Norshamsuri Ali @ Hasim

Magnetic resonant coupling (MRC) is one of the techniques that are widely used in wireless power transfer (WPT) systems. The technique is commonly used for enhancing distance while maintaining power transfer efficiency (PTE). Many studies have investigated new technologies to extend the distance of MRC while maintaining high PTE values. The most promising technique to date in MRC is the addition of a resonator between the transmitter and the receiver coil. The implementation of the resonator varies based on different designs, sizes, and material types, although the outcomes remain unsatisfactory. By introducing dielectric material resonators, PTE can be improved by lowering the ohmic loss which becomes a problem on conventional resonators. This study presents a general overview on the use of dielectric material as a resonator in MRC WPT technology and its technological development. The basic operation of MRC WPT is summarized with up-to-date technical improvements related to dielectric material as a resonator in the field of WPT. An overview of the current limitations and challenges of this technique is also highlighted in this study.

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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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Properties of a new insulation material glass bubble in geopolymer concrete

2021 , Noor Fifinatasha Shahedan , Mohd. Mustafa Al Bakri Abdullah , Norsuria Mahmed , Andri Kusbiantoro , Sam Tammas-Williams , Petrică Vizureanu , Jerzy J. Wysłocki , Ikmal Hakem Aziz , Katarzyna Błoch , Marcin Nabiałek

This paper details analytical research results into a novel geopolymer concrete embedded with glass bubble as its thermal insulating material, fly ash as its precursor material, and a combination of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) as its alkaline activator to form a geopolymer system. The workability, density, compressive strength (per curing days), and water absorption of the sample loaded at 10% glass bubble (loading level determined to satisfy the minimum strength requirement of a load-bearing structure) were 70 mm, 2165 kg/m3, 52.58 MPa (28 days), 54.92 MPa (60 days), and 65.25 MPa (90 days), and 3.73 %, respectively. The thermal conductivity for geopolymer concrete decreased from 1.47 to 1.19 W/mK, while the thermal diffusivity decreased from 1.88 to 1.02 mm2/s due to increased specific heat from 0.96 to 1.73 MJ/m3K. The improved physicomechanical and thermal (insulating) properties resulting from embedding a glass bubble as an insulating material into geopolymer concrete resulted in a viable composite for use in the construction industry.

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Thermal insulation properties of insulated concrete

2019-01-01 , Shahedan N.F. , Mohd. Mustafa Al Bakri Abdullah , Norsuria Mahmed , Kusbiantoro A. , Kamarudin Hussin , Sandu A.V. , Naveed A.

In building development, concrete is world most reliable, durable and versatile in construction materials. However, the heating and cooling system of the building is influenced by outside temperature due to extreme weather or areas condition leads to the consumption of a lot of electrical power. Thermally insulated concretes represent alternative construction materials to improve the thermal efficiency in building development. Various construction materials have different thermal insulation properties and thus, their suitability for various conditions vary. Thermal insulation properties are generally identified through specific heat, thermal conductivity, thermal diffusivity, thermal expansion, and mass loss. This paper present review the thermal insulation properties of variations insulated concrete are presently in growing demand of researchers to comfort and resolve prescribed issues related to insulated concrete in enhancing thermal insulation properties as a passive energy saving building.

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Electrical Performance of Curcuma longa Extract Dye using SnO2-Based Photoanode Dye-Sensitized Solar Cell

2022-12-01 , Siti Norhafizah Idris , Ili Salwani Mohamad , Norsuria Mahmed , Mohd Natashah Norizan , Magiswaran K. , Abas Z.A.

Due to their low output costs, straightforward manufacturing, and high effectiveness, dye-sensitized solar cell (DSSC) has a large following interest in the solar energy industry. Furthermore, due to its outstanding properties, tin oxide (SnO2) is an appealing semiconducting material suitable as a photoanode in DSSCs. In this research, the photoelectrodes of DSSC were fabricated using commercial SnO2 nanoparticles and sensitized with inorganic and organic dyes, N719 and Curcuma longa (turmeric) extract dye. On top of that, a platinum (Pt) counter electrode, iodide electrolyte and fluorine-doped tin oxide (FTO) coated glass substrate were used to fabricate the DSSC. The crystallographic structure and surface morphology of the SnO2 nanopowder were identified using X-ray diffraction (XRD) and scanning electron microscopy (SEM) characterizations respectively. In addition, UV-Visible and current density-voltage curves were used to analyze the optical properties of the photoanodes and the cell’s electrical performance. As a result, it was found that the DSSC fabricated with N719 dye exhibited higher efficiency in contrast with the turmeric extract dye with SnO2 photoanodes.

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The Effect of Spinacia oleracea Dye Absorption Time on ZnO-based Dye-Sensitized Solar Cells’ Electrical Performance

2022-12-01 , Magiswaran K. , Ili Salwani Mohamad , Norsuria Mahmed , Mohd Natashah Norizan , Idris S.N. , Abas Z.A.

Dye-sensitized solar cells (DSSC) have attracted much attention over the past 20 years due to their significance in energy conversion. However, the dye soaking time may significantly impact the efficacy of the photoanode semiconductor to carry the electronic charge to which the dye molecules adhere. An optimized dye soaking time may prevent the recombination of photo-excited electrons that are injected into the semiconductor of the DSSC. This study scrutinized the dependence of the zinc oxide (ZnO) photoanode soaking time of Spinacia oleracea (spinach) dye on the photocurrent-voltage characteristics. The ZnO film layer (photoanode) was prepared with commercial ZnO nanopowder and applied onto a fluorine-doped tin oxide (FTO) glass substrate using the doctor blade method. The prepared DSSCs’ were subjected to a variety of characterizations, including current density-voltage (J-V) characterization, UV-visible characterization, scanning electron microscope (SEM), and X-ray diffraction (XRD). Comparing four variations of dye soaking time, ZnO-based DSSC photoanode soaked in the dye for an hour achieved an optimum efficiency of 0.03 %. This study proved that the efficiency of a DSSC can be improved by optimizing the dye soaking time.

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Adsorption efficiency and photocatalytic activity of silver sulphide-activated carbon (Ag₂S-AC) composites

2025 , Siti Norsaffirah Zailan , Norsuria Mahmed , Aissa Bouaissi , Zahra Ramadlan Mubarokah , Mohd Natashah Norizan , Nurfina Yudasari , Ili Salwani Mohamad , Siti Salwa Mohammad Shirajuddin

Background: This study investigates the adsorption efficiency and photocatalytic activity of silver sulphide-activated carbon (Ag₂S-AC) composites derived from ground coffee waste (GCW). Methods: In this work, GCW was preceding to carbonized at 500 ± 2°C for hours and formed biochar. Then, GCW was subjected to activation using hydrochloric acid (HCl), phosphoric acid (H₃PO₄) and potassium hydroxide (KOH). The mixture was left to soak for 24 h at room temperature, followed by carbonization at 350 and 500˚C. In the meantime, the silver sulphide (Ag₂S) was synthesized by using an ion exchange method. Sodium sulphide (Na₂S) was used as sulphur source and mixed with silver nitrate (AgNO₃) and sodium citrate (NaCit) for two hours, then dried in oven at 50 ± 2°C for 10 h. Next, the carbonized AC was subsequently combined with synthesized silver sulphide, resulting in the creation of Ag₂S-activated carbon composites that functioned both as adsorbent and photocatalyst. Their capabilities as adsorbents and photocatalyst were studied by using copper ions (Cu2+) and methylene blue (MB) solution. Significance findings: Based on results, GCW and all the prepared activated carbons are in the amorphous phase, except for the Ag₂S-AC composites, where the Ag₂S peak reflection can be observed from the X-ray diffraction (XRD) pattern. GCW shows rough and dense surface morphology. The AC shows different pore sizes and structures depending on the chemical activators used, where AC-KOH shows the largest pore size (165.31 μm). The existence of micropores can be observed in all the activated carbon samples. For the adsorption of Cu2+, all samples show more than 99 % of the removal efficiency. While for photocatalytic testing, the Ag₂S-H₃PO₄ sample shows the highest degradation rate (97.7 %) of MB solutions.

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Photocatalytic Behaviour of TiO2-geopolymer Paste under Sunlight

2020-11-24 , Zailan Siti Norsaffirah , Norsuria Mahmed , Mohd. Mustafa Al Bakri Abdullah

The photocatalytic degradation of methylene blue (MB) of the geopolymer paste with addition nanoparticles titanium dioxide (TiO2) was investigated under illumination of sunlight radiation. In this work, TiO2-based geopolymer paste was prepare by dry mixing of Class F fly ash (FA) and different amount of nano-TiO2 (0, 2.5, 5.0, 10.0 & 15.0 wt%). Then, the alkali activator, which is combination of sodium hydroxide solution with sodium silicate was added to the dry mix FA-TiO2 with ratio of 2.5. All the sample was cured at room temperature and aged for 28 days. The photocatalytic behaviour of nano-TiO2 was evaluated and compared through photocatalytic testing and surface degradation testing by measuring the photodegradation of MB under sunlight rays. The experimental results revealed that the addition of nano-TiO2 to the geopolymer paste shows excellent result on photocatalytic degradation of MB after exposure to sunlight up to 150 minutes.

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Near-Infrared (NIR) Silver Sulfide (Ag₂S) Semiconductor Photocatalyst Film for Degradation of Methylene Blue Solution

2023-01-01 , Mubarokah Z.R. , Norsuria Mahmed , Mohd Natashah Norizan , Ili Salwani Mohamad , Mohd. Mustafa Al Bakri Abdullah , Błoch K. , Nabiałek M. , Baltatu M.S. , Sandu A.V. , Vizureanu P.

A silver sulfide (Ag2S) semiconductor photocatalyst film has been successfully synthesized using a solution casting method. To produce the photocatalyst films, two types of Ag2S powder were used: a commercialized and synthesized powder. For the commercialized powder (CF/comAg2S), the Ag2S underwent a rarefaction process to reduce its crystallite size from 52 nm to 10 nm, followed by incorporation into microcrystalline cellulose using a solution casting method under the presence of an alkaline/urea solution. A similar process was applied to the synthesized Ag2S powder (CF/syntAg2S), resulting from the co-precipitation process of silver nitrate (AgNO3) and thiourea. The prepared photocatalyst films and their photocatalytic efficiency were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and UV-visible spectroscopy (UV-Vis). The results showed that the incorporation of the Ag2S powder into the cellulose films could reduce the peak intensity of the oxygen-containing functional group, which indicated the formation of a composite film. The study of the crystal structure confirmed that all of the as-prepared samples featured a monoclinic acanthite Ag2S structure with space group P21/C. It was found that the degradation rate of the methylene blue dye reached 100% within 2 h under sunlight exposure when using CF/comAg2S and 98.6% for the CF/syntAg2S photocatalyst film, and only 48.1% for the bare Ag2S powder. For the non-exposure sunlight samples, the degradation rate of only 33–35% indicated the importance of the semiconductor near-infrared (NIR) Ag2S photocatalyst used.

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