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result(s) for
"Mohd Zaid, Mohd Hafiz"
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Effect of ZnO on the Physical Properties and Optical Band Gap of Soda Lime Silicate Glass
by
Mohd Ghazali, Mohd Sabri
,
Matori, Khamirul Amin
,
Zakaria, Azmi
in
Calcium Compounds - chemistry
,
Glass
,
Glass - chemistry
2012
This manuscript reports on the physical properties and optical band gap of five samples of soda lime silicate (SLS) glass combined with zinc oxide (ZnO) that were prepared by a melting and quenching process. To understand the role of ZnO in this glass structure, the density, molar volume and optical band gaps were investigated. The density and absorption spectra in the Ultra-Violet-Visible (UV-Visible) region were recorded at room temperature. The results show that the densities of the glass samples increased as the ZnO weight percentage increased. The molar volume of the glasses shows the same trend as the density: the molar volume increased as the ZnO content increased. The optical band gaps were calculated from the absorption edge, and it was found that the optical band gap decreased from 3.20 to 2.32 eV as the ZnO concentration increased.
Journal Article
Anticorrosive and Microbial Inhibition Performance of a Coating Loaded with Andrographis paniculata on Stainless Steel in Seawater
by
Hamidi, Nur Aiman Syafiq Mohd
,
Matori, Khamirul Amin
,
Shaifudin, Muhamad Syaizwadi
in
Additives
,
Andrographis paniculata
,
Bacteria
2021
With the trend for green technology, the study focused on utilizing a forgotten herb to produce an eco-friendly coating. Andrographis paniculata or the kalmegh leaves extract (KLE) has been investigated for its abilities in retarding the corrosion process due to its excellent anti-oxidative and antimicrobial properties. Here, KLE was employed as a novel additive in coatings and formulations were made by varying its wt%: 0, 3, 6, 9, and 12. These were applied to stainless steel 316L immersed in seawater for up to 50 days. The samples were characterized and analyzed to measure effectiveness of inhibition of corrosion and microbial growth. The best concentration was revealed to be 6 wt% KLE; it exhibited the highest performance in improving the ionic resistance of the coating and reducing the growth of bacteria.
Journal Article
Effects of Calcination Holding Time on Properties of Wide Band Gap Willemite Semiconductor Nanoparticles by the Polymer Thermal Treatment Method
2018
Willemite is a wide band gap semiconductor used in modern day technology for optoelectronics application. In this study, a new simple technique with less energy consumption is proposed. Willemite nanoparticles (NPs) were produced via a water–based solution consisting of a metallic precursor, polyvinylpyrrolidone (PVP), and underwent a calcination process at 900 °C for several holding times between 1–4 h. The FT–IR and Raman spectra indicated the presence of metal oxide bands as well as the effective removal of PVP. The degree of the crystallization and formation of the NPs were determined by XRD. The mean crystallite size of the NPs was between 18.23–27.40 nm. The morphology, particle shape and size distribution were viewed with HR-TEM and FESEM analysis. The willemite NPs aggregate from the smaller to larger particles with an increase in calcination holding time from 1–4 h with the sizes ranging between 19.74–29.71 nm. The energy values obtained from the experimental band gap decreased with increasing the holding time over the range of 5.39 eV at 1 h to at 5.27 at 4 h. These values match well with band gap obtained from the Mott and Davis model for direct transition. The findings in this study are very promising and can justify the use of these novel materials as a potential candidate for green luminescent optoelectronic applications.
Journal Article
Effects of Particle Size on the Dielectric, Mechanical, and Thermal Properties of Recycled Borosilicate Glass-Filled PTFE Microwave Substrates
by
Abbas, Zulkifly
,
Mohd Zaid, Mohd Hafiz
,
Alhaji, Ibrahim Abubakar
in
Borosilicate glass
,
Calibration
,
Dielectric loss
2021
Low dielectric loss and low-cost recycled borosilicate (BRS) glass-reinforced polytetrafluoroethylene (PTFE) composites were fabricated for microwave substrate applications. The composites were prepared through a dry powder processing technique by dispersing different micron sizes (25 µm, 45 µm, 63 µm, 90 µm, and 106 µm) of the recycled BRS filler in the PTFE matrix. The effect of the filler sizes on the composites’ thermal, mechanical, and dielectric properties was studied. The dielectric properties of the composites were characterised in the frequency range of 1–12 GHz using an open-ended coaxial probe (OCP) connected to a vector network analyser (VNA). XRD patterns confirmed the phase formation of PTFE and recycled BRS glass. The scanning electron microscope also showed good filler dispersion at larger filler particle sizes. In addition, the composites’ coefficient of thermal expansion and tensile strength decreased from 12.93 MPa and 64.86 ppm/°C to 7.12 MPa and 55.77 ppm/°C when the filler size is reduced from 106 μm to 25 μm. However, moisture absorption and density of the composites increased from 0.01% and 2.17 g/cm3 to 0.04% and 2.21 g/cm3. The decrement in filler size from 106 μm to 25 μm also increased the mean dielectric constant and loss tangent of the composites from 2.07 and 0.0010 to 2.18 and 0.0011, respectively, while it reduced the mean signal transmission speed from 2.088 × 108 m/s to 2.031 × 108 m/s. The presented results showed that PTFE/recycled BRS composite exhibited comparable characteristics with commercial high-frequency laminates.
Journal Article
Synthesis of Eu3+-Doped ZnO/Zn2SiO4 Composite Phosphor for Potent Optoelectronic Applications
by
Mustapha, Haslinawati Mohd
,
Yaakob, Yazid
,
Matori, Khamirul Amin
in
Absorption spectra
,
Composite materials
,
Condensed Matter
2022
Eu
3+
-doped Zn
2
SiO
4
/ZnO phosphor-based composites were prepared using a simple thermal treatment method. The effect of Eu
3+
content on the morphological and photoluminescence performance was examined using XRD, FTIR, FESEM, UV–Vis, and PL measurement. The existence of two crystal phases by the XRD measurement confirmed the development of zincite (ZnO) and zinc silicate (Zn
2
SiO
4
) crystal phases. Besides, the FTIR spectra and FESEM micrograph support the XRD result by verifying ZnO and Zn
2
SiO
4
phase formation through the existence of their characteristic Zn–O–Si and Zn–O vibration modes with the decrement of SiO
4
broad absorption band as the Eu
3+
concentration increased. Also, UV–Vis absorption spectra presented by the composite samples displayed a broad absorbance that confirmed the addition of Eu
3+
ions in the ZnO/Zn
2
SiO
4
has caused the absorption edge of the curve having red shift. The photoluminescence spectrum showed red shift light emissions at 485 and 615 nm, associating with the Zn
2
SiO
4
crystal phase, in addition to the ZnO crystal phase. From the interesting results achieved, this ZnO/Zn
2
SiO
4
phosphor-based composite material can be a potent candidate in optoelectronic applications.
Journal Article
Impact of Dy2O3 Substitution on the Physical, Structural and Optical Properties of Lithium–Aluminium–Borate Glass System
by
Bagi Aljewaw, Osama
,
Che Isa, Iza Nurzawani
,
Abu Mhareb, Mohammad Hasan
in
borate glass
,
Boron
,
Dy2O3
2020
In this study, a series of Li2O-Al2O3-B2O3 glasses doped with various concentrations of Dy2O3 (where x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0 mol%) were prepared by using a conventional melt-quenching technique. The structural, physical and optical properties of the glasses were examined by utilising a variety of techniques instance, X-ray diffraction (XRD), UV–Vis-NIR spectrometer, Fourier transform infrared (FTIR) and photoluminescence (PL). The XRD spectra demonstrate the amorphous phase of all glasses. Furthermore, the UV-vis-NIR spectrometers have registered optical absorption spectra a numbers of peaks which exist at 1703, 1271, 1095, 902, 841, 802, 669, 458, 393 and 352 nm congruous to the transitions from the ground of state (6H15/2) to different excited states, 6H11/2, 6F11/2 + 6H9/2, 6F9/2 + 6H7/2, 6F7/2, 6F5/2, 6F3/2, 4F9/2, 4I15/2, 4F7/2 and 6P7/2, respectively. The spectra of emission exhibit two strong emanation bands at 481 nm and 575 nm in the visible region, which correspond to the transitions 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2. All prepared glass samples doped with Dy2O3 show an increase in the emission intensity with an increase in the concentration of Dy3+. Based on the obtained results, the aforementioned glass samples may have possible applications, such as optical sensor and laser applications.
Journal Article
The Effect of WO3-Doped Soda Lime Silica SLS Waste Glass to Develop Lead-Free Glass as a Shielding Material against Radiation
by
Shahrim Mustafa, Iskandar
,
Abdul Malik, Muhammad Fadhirul Izwan
,
Almuqrin, Aljawhara H.
in
Concrete
,
Environmental impact
,
Gamma rays
2022
The current study aims to enhance the efficiency of lead-free glass as a shielding material against radiation, solve the problem of the dark brown of bismuth glass, and reduce the accumulation of waste glass disposed in landfills by using soda-lime-silica SLS glass waste. The melt-quenching method was utilized to fabricate (WO3)x [(Bi2O3)0.2 (ZnO)0.3 (B2O3)0.2 (SLS)0.3]1−x at 1200 °C, where x = (0, 0.01, 0.02, 0.03, 0.04, and 0.05 mol). Soda lime silica SLS glass waste, which is mostly composed of 74.1 % SiO2, was used to obtain SiO2. Radiation Attenuation parameters were investigated using narrow-beam geometry and X-ray fluorescence (XRF). Furthermore, the parameters related to radiation shielding were calculated. The results showed that when WO3 concentration was increased, the half-value layer was reduced, whereas the μ increased. It could be concluded that WBiBZn-SLS glass is a good shielding material against radiation, nontoxic, and transparent to visible light.
Journal Article
Development of Novel Transparent Radiation Shielding Glasses by BaO Doping in Waste Soda Lime Silica (SLS) Glass
by
Izwan Abdul Malik, Muhammad Fadhirul
,
Seth Ezra, Nabasu
,
Mustafa, Iskandar Shahrim
in
Atoms & subatomic particles
,
Gamma rays
,
Geometry
2022
In the current study, BaO was doped in Bi2O3-ZnO-B2O3-SLS glass to develop lead-free radiation shielding glasses and to solve the dark brown of bismuth glass. The melt-quenching method was utilized to fabricate (x) BaO (1 − x)[0.3 ZnO 0.2 Bi2O3 0.2 B2O3 0.3 SLS] (where x are 0.01, 0.02, 0.03, 0.04, and 0.05 mol) at 1200 °C. Soda lime silica glass waste (SLS), which is mostly composed of 74.1% SiO2, was used to obtain SiO2. The mass attenuation coefficient (μm) was investigated utilizing X-ray fluorescence (XRF) at 16.61, 17.74, 21.17, and 25.27 keV and narrow beam geometry at 59.54, 662, and 1333 keV. Moreover, the other parameters related to gamma ray shielding properties such as half-value layer (HVL), mean free path (MFP), and effective atomic number (Zeff) were computed depending on μm values. The results indicated that HVL and MFP decreased, whereas μm increased with an increase in BaO concentration. According to these results, it can be concluded that BaO doped in Bi2O3-ZnO-B2O3-SLS glass is a nontoxic, transparent to visible light, and a good shielding material against radiation.
Journal Article
Influence of Eu3+ Ions on Elastic Moduli and Microhardness of Zinc-boro-soda-lime-silica Glass System
by
Cheong, Wei Mun
,
Matori, Khamirul Amin
,
Tee, Tan Sin
in
Boron oxides
,
Bulk density
,
Chemistry
2024
This study focuses on zinc-boro-soda-lime-silica (ZnO − B
2
O
3
− SLS) glasses produced through fast-cooling melt-quenching. The influence of Eu
3+
ions on glass properties is explored. As Eu
3+
concentration rises, bulk density and molar volume increase from 3.423 to 3.484 g/cm
3
and 21.760 to 23.768 cm
3
/mol, respectively. X-ray diffraction indicates amorphous phase dominance supported by glassy surface morphology. Ultrasonic measurements show the increasing and decreasing trend for ultrasonic velocities and elastic moduli with increasing Eu
3+
concentration. Poisson’s ratio of the samples signifies their low cross-link density behavior. Moreover, the ZBS-3Eu presents the highest microhardness value of 4.776 GPa. The sample’s fractal bond connectivity varies from 1.814 to 2.051, suggesting a 2D structure. Likewise, the ZBS-3Eu glass sample exhibits the most rigidity attributed to its highest
f
g
value of 0.075. These findings suggest that ZBS-3Eu has the potential for applications requiring high-strength glass.
Journal Article
Phase Transformations of α-Alumina Made from Waste Aluminum via a Precipitation Technique
by
Wah, Loy
,
Matori, Khamirul
,
Zaid, Mohd
in
Aluminum - chemistry
,
Aluminum Oxide - chemistry
,
Chemical Precipitation
2012
We report on a recycling project in which α-Al2O3 was produced from aluminum cans because no such work has been reported in literature. Heated aluminum cans were mixed with 8.0 M of H2SO4 solution to form an Al2(SO4)3 solution. The Al2(SO4)3 salt was contained in a white semi-liquid solution with excess H2SO4; some unreacted aluminum pieces were also present. The solution was filtered and mixed with ethanol in a ratio of 2:3, to form a white solid of Al2(SO4)3·18H2O. The Al2(SO4)3·18H2O was calcined in an electrical furnace for 3 h at temperatures of 400–1400 °C. The heating and cooling rates were 10 °C /min. XRD was used to investigate the phase changes at different temperatures and XRF was used to determine the elemental composition in the alumina produced. A series of different alumina compositions, made by repeated dehydration and desulfonation of the Al2(SO4)3·18H2O, is reported. All transitional alumina phases produced at low temperatures were converted to α-Al2O3 at high temperatures. The X-ray diffraction results indicated that the α-Al2O3 phase was realized when the calcination temperature was at 1200 °C or higher.
Journal Article