M. H. Mamat

Universiti Teknologi MARA | UiTM · School of Electrical Engineering

Polyvinylidene fluoride (PVDF)/titanium dioxide (TiO2)/graphene oxide (GO)-based hybrid membrane was blended with polymer additive of polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP) and poly (methyl methacrylate) (PMMA) through phase inversion method. A triple-tail surfactant was utilised to assist the initial GO synthesis and achieve better GO...

This study fabricated tantalum (Ta)-doped titanium dioxide with a unique nanorod-assembled actinomorphic-flower-like microsphere structured film . The Ta-doped TiO2 actinomorphic-flower-like microsphere (TAFM) was fabricated via the solution immersion method in a Schott bottle with a home-made improvised clamp. The samples were characterised using...

Chemical doped multiferroic BiFeO3 has received much research interest from both fundamental and applications due to enhanced magnetism, reduced leakage current, increased piezoelectric effect and novel optical responds. Here, we report on a theoretical investigation of structural, electronic and optical properties of Al doped BiFeO3 using density...

In this study, natural dye sensitisers derived from ketum (Mitragyna speciosa-MS), spinach (Spinacia oleracea-SO), curry (Murraya koenigii-MK), papaya (Carica papaya-CP), and henna (Lawsonia inermis-LI) were investigated for dye-sensitised solar cells (DSSCs). Ultraviolet-Visible Spectroscopy (UV-Vis), Fourier Transform Infrared spectroscopy (FTIR)...

This study synthesized pristine and aluminum (Al)-doped zinc oxide (Al:ZnO) nanostructures through a simplistic low-temperature ultrasonicated solution immersion method. Al:ZnO nanostructures were synthesized as a sensing material using different immersion times varying from two to five hours. The Al:ZnO nanostructured-based flexible humidity senso...

The effect on structural, morphological and optical characteristics towards humidity sensing capability was elucidated as humidity-sensitive sensing material that is made by composting zinc oxide nanostructured powder (ZN) nanoparticles with varying capacities of reduced graphene oxide (rGO). The ZN was successfully synthesized through the ultrason...

Dye co-sensitization technique is a promising strategy adopted to establish a broader absorption wavelength and higher spectral response towards panchromatic light-harvesting of dye-sensitized solar cells, DSSC. In this work, the co-sensitizing between chlorophyll pigment extracted from Mitragyna Speciosa (kratom) and anthocyanin pigment extracted...

Humidity sensors have become increasingly important and widely used to improve the quality of life and industrial processes. Over the past decades, titanium dioxide (TiO2) has received wide attention in many promising areas such as sensors, solar cells, and photocatalytic. However, TiO2 required high operating conditions such as high temperatures t...

The influence of thermal annealing on the surface morphologies and structural characteristics of zinc oxide (ZnO) nanopowders synthesized via the solution immersion method for triboelectric nanogenerator applications is reported in this paper. The ZnO nanopowders were thermally treated at different temperatures of annealing in the ranges between 30...

The zinc oxide (ZnO) and copper-doped ZnO (Cu:ZnO) films were synthesized by an immersion method on a sheet of aluminium foil as a substrate. Investigations were conducted into how heat treatment affected the output nanogenerator performance, surface morphological characteristics and structural properties. The field emission scanning electron micro...

Nanogenerators have been widely discussed and investigated in the literature due to their excellent development in various sectors and applications. There are two typical electricity generating mechanisms involved in nanogenerators, that include piezoelectric and triboelectric processes. The selection of materials in developing nanogenerator applic...

For the first time, a rutile phased tin oxide (SnO2) nanosheet was assembled onto a zinc oxide (ZnO) nanorod array to form SnO2 nanosheet/ZnO nanorod array heterostructure films (TSZR) using a two-step solution immersion method. This study offers a facile and effective path to grow a SnO2 nanosheet assembled layer on ZnO nanorod arrays with a varie...

Here, we report the successful incorporation of group I elements (K, Na, Li) to ZnO nanowires. Three distinct (2, 4, and 6 wt.%) doping concentrations of group I elements have been used to generate high piezoelectric voltage by employing a vertically integrated nanowire generator (VING) structure. X-ray photoelectron spectra (XPS) indicated the see...

This study presents a simpler approach to directly synthesize graphene oxide (GO) via electrochemical exfoliation method utilizing customized triple-tail 1-butyl-3-methyl-imidazolium, 1, 4-bis(neopentyoxy)-3-(neopentyloxycarbonyl)-1, 4-dioxobutane-2-sulfonate (BMIM-TC14) and sodium 1,4-bis(neopentyloxy)-3-(neopentylcarbonyl)-1,4-dioxobutane-2-sulfo...

Unique three-dimensional (3D) titanium dioxide (TiO2) nanoflowers (TFNA) have shown great potential for humidity sensing applications, due to their large surface area-to-volume ratio and high hydrophilicity. The formation of a composite with other materials could further enhance the performance of this material. In this work, the effect of differen...

ZnO/CuO nanocomposite thin films were deposited at different ratio, 50:50, 60:40, 70:30, 80:20 and 90:10 using sol – gel spin coating technique on glass substrates. The thin films were annealed at 500°C for 1 hour at room ambient after the deposition process. The structural, optical and electrical properties of the thin films were characterized by...

This work presents a nanocomposite-based humidity sensor based on zinc oxide nanostructured powder (ZNP) nanoparticles that achieves a maximum enhancement in the humidity sensing performance at room temperature due to the introduction of different amounts of reduced graphene oxide (rGO) loading from 0.5 wt.% to 2.0 wt.%. The rGO/ZNP (rZNP) nanocomp...

Pristine zinc oxide (ZnO) has various limitations that severely limit the development of ZnO as humidity sensors. However, doping, co-doping, and the implementation of composite structures are excellent methods for improving ZnO nanostructures’ structural, optical, and electrical properties. This review will reveal and discussed various dopant impu...

The aim of the paper is to study a distribution of ions inside a zinc oxide (ZnO) target during sputtering process using different gases. The plots of ion distribution were obtained from the simulation results using Stopping and Range of Ions in Matter (SRIM)-2013 software. Generally, the SRIM software is utilized to calculate a variety of paramete...

Advancement to the performance of humidity sensor is an importance subject due to its diverse role in multitude of applications. The trend shows that researchers are using various approaches to tackle the performance issues of humidity sensor. This paper reviews recent progress on the improvement of titanium dioxide-based humidity sensor performanc...

This paper presents the effects of operating parameters on the photocatalytic degradation of methylene blue using flowerlike rutile-phase TiO2 films synthesised by a hydrothermal method. The findings show that numerous parameters such as the catalyst morphology, the presence of oxygen vacancy/Ti³⁺ surface defects, initial pH of methylene blue solut...

We have prepared waste curry leaves extract derived carbon dots (CL-C dots) by microwave assisted method. The synthesized CL-C dots were well characterized by many techniques. Using HR-TEM images, the size of the synthesized CL-C dots were determined to be 3.55 nm. CL-C dots exhibits green fluorescence and obtained emission maximum at 425 nm upon t...

This article summarizes the strain‐mediated electrical and optical properties of novel lead‐free xCuFe2O4 (1 − x) KNbO3 (x = 0.2, 0.3, and 0.4) multiferroic nanocomposite through a solid state route. X‐ray diffraction analysis divulges the influence of interfacial strain in the KNbO3–CuFe2O4 matrix and shows the coexistence of orthorhombic and cubi...

Herein we are reporting, the in-situ synthesis of polydopamine capped silver nanoparticles (PDA-AgNPs) and its cysteamine (CYS) and tetracycline (TC) drugs sensor applications. The synthesized PDA-AgNPs was characterized by UV–Visible, Fourier Transformed–Infrared, X-Ray Diffraction, Zeta Potential, and High Resolution-Transmission Electron Microsc...

Here, we report high output voltage generation by employing p-type ZnO nanowires as an integral part of vertically integrated nanowire generators (VING). Study has been carried out to generate high piezoelectric voltage by introducing impurities to ZnO nanowires from group V (P, As, Sb) elements which worked as acceptor impurities for intrinsically...

We report on the novel multiferroic (x)CuFe2O4 − (1 − x)KNbO3 (x = 0.2, 0.3, and 0.4) nanocomposite prepared by conventional solid state route. Structural analysis reveals that a perovskite orthorhombic phase corresponding to KNbO3 and cubic spinel phase corresponding to CuFe2O4 were simultaneously present in each nanocomposite. All the nanocomposi...

Hypothesis As compared to common aliphatic surfactants, increasing the number of pendant or incorporated aromatic groups in a surfactant is expected to offer significant enhancement in the affinity for graphene surfaces. The basis for enhanced graphene-philicity of aromatic surfactants is that they can develop appreciable π – π interactions with gr...

We are reporting the synthesis of mannitol derived carbon dots (MCDs) and their application as silver ion and thiamine sensors. The synthesized MCDs were characterized by HR-TEM, FT-IR, UV–visible, fluorescence, XRD and Raman methods. The synthesized MCDs exhibit a blue emission at 444 nm and the quantum yield of the MCDs is 43.8%. The MCDs particl...

In this work, a new chlorophyll dye-sensitiser derived from mitragyna speciosa (MS) leaves, also known as Kratom, was employed for dye-sensitised solar cells (DSSCs). The influence of magnesium sulfate (MgSO4), a low-cost dye additive, and suitable extraction solvents on the performance of DSSCs were examined. Here, the optical properties were inve...

This study investigates how utilizing an environmentally friendly alum dye co-adsorbent impacts the overall performances of dye-sensitized solar cells (DSSCs). Various alum concentrations were added to anthocyanin-based blackberry dye solutions during the 24-hour dye immersion process. It was discovered that the alum dissolution process increased a...

In this study, an organic dye sensitizer derived from blackberry fruits was employed, and the influence of aluminium sulphate, Al2(SO4)3. H2O (alum) as a bi-functional (acidification and flocculation) additive in DSSC was investigated. The alum treated dye solution, ATD, was created by adding 0.1 g alum to the dye solution prior to the immersion op...

Chemical pollutants emitted by the textile industry are a major source of water contamination, resulting in dangerous diseases and most of the effluent treatment techniques are relatively ineffective. As a result, metal oxide-based photocatalysts emerged as a viable alternative to the already existing dye treatment methods. The current work focused...

In this study, different titanium dioxide (TiO2) nanostructures and phase were investigated as photoanode film for application in dye-sensitized solar cells. Rutile TiO2 nanorods (NRs)-nanotrees (NTs) and TiO2 NRs-microcauliflowers (MCFs) were synthesized via hydrothermal method for different time. The mixed phase of rutile-anatase film was fabrica...

In this work, waste cooking palm oil (WCPO)-based carbon nanotubes (CNTs) with encapsulated iron (Fe) nanoparticles have been successfully produced via modified thermal chemical vapor deposition method. Based on several characterizations, the dense WCPO-based CNT was produced with high purity of 89% and high crystallinity proven by low ID/IG ratio...

The nickel oxide (NiO) nanosheet/nanoflower-like (NS/NF) films-based humidity sensors doped with zinc (Zn) and without doping were successfully deposited on the NiO seed layer-coated glass substrates using the immersion method. The addition of 1 atomic percent of Zn concentration into pristine NiO has a significant influence on the structural and m...

To date, the deposition of AlGaN thin film using the co-sputtering technique at room temperature has not been reported yet. The use of AlGaN for electronic devices has been widely known because of its ultra-wide bandgap. However, to deposit the AlGaN thin film and achieved high quality of AlGaN films, higher temperature or extra time deposition are...

Purpose This study aims to investigate the effect of temperature applied at the initial deposition of Aluminium Nitride (AlN) thin-film on a silicon substrate by high-power impulse magnetron sputtering (HiPIMS) technique. Design/methodology/approach HiPIMS system was used to deposit AlN thin film at a low output power of 200 W. The ramping tempera...

Previously, surfactant-assisted exfoliated graphene oxide (sEGO) formed with the triple-chain surfactant TC14 (sodium 1,4-bis(neopentyloxy)-3-(neopentylcarbonyl)-1,4-dioxobutane-2-sulfonate) was applied in wastewater treatment. The extent of dye-removal and adsorption capacity of the sEGO formed with this triple-chain surfactant outperformed those...

Here, we report high output piezoelectric voltage generation using ZnO nanowires oxidized at high temperature. The study has been carried out to observe behavior of ZnO nanowires in the presence of strong oxidizing gases (O, CO2, and NO2) at elevated temperature. The focus of the research was to generate high piezoelectric voltage by using surface...

The novel hematite (α-Fe2O3)/nickel oxide (NiO) heterostructures were grown on fluorine-doped tin oxide (FTO) coated glass substrates at various deposited NiO of 3, 5, and 7 layers. The heterostructures were successfully synthesized using the immersion and sol–gel spin coating methods for α-Fe2O3 and NiO films, respectively. The field emission scan...

In this work, single phase Bismuth Ferrite, BiFeO 3 was successfully synthesized by using hydrothermal method assisted with different weight (0.24 g, 0.36 g and 0.48 g) of Chitosan. Potassium hydroxide (KOH) were used as a mineralizer during the synthesis process for the precipitation. The samples were characterized for different properties such as...

Surface‐modified zinc ferrite nanocomposites were successfully prepared thru ultrasonic impregnation technique by taking kapok fiber as a bio‐template. This work demonstrates a fast preparation method to produce the bio‐templated ZnFe2O4 composite photocatalyst. The templating method for photocatalyst is favorable due to the benefit of a large surf...

This paper reviews the piezoelectricity in the ZnO which having enough feasibility for flexible piezoelectric energy harvesting. ZnO is chosen as a new lead-free replacement material of PZT due to its great advantages for piezoelectric material. The low cost and small-time require for the synthesis of ZnO thin films for industrial requirements are...

Aluminium zinc oxide (AZO) thin film has been fabricated using a spray pyrolysis method. The thin film deposition has been carried out by spray pyrolysis on Teflon substrates. The structural properties of AZO thin films were characterized using X-Ray Diffraction (XRD) for the crystallinity of AZO thin films. The structural analysis of AZO thin film...

Here, we report high output voltage generation via oxidized ZnO nanowires. A thorough study has been carried out to observe the behavior of ZnO nanowires under reduced grain size and high temperature conditions. Study has revealed that piezoelectric output voltage generated by ZnO based VING (vertically integrated nanowire generator) has been gradu...

In this work, sand/zinc oxide (ZnO)/titanium dioxide (TiO 2)-based photocatalysts were hybridized with graphene oxide (GO) and GO_multi-walled carbon nanotubes (MWCNTs) hybrid solution. The novel hybrid was then used in photocatalysis to degrade dye contamination. The nanocomposite photocatalyst was initially fabricated by growing ZnO nanorods (NRs...

Titanium dioxide (TiO2) nanotube arrays (NTAs) material have received attention due to their high stability in optoelectronic devices. As-prepared TiO2 nanotubes layers are amorphous and their properties are not sufficient enough to applied in device applications. The TiO2 NTAs was synthesized by electrochemical anodization method. The medium was m...

Undoped ZnO and ZnO doped with various concentration of TiO2 (ZnO:TiO2) at 1, 3, 5, 7 and 9 wt% were prepared on ZnO seeded layer coated glass substrate by hydrothermal method. Based on XRD analysis, the crystallite size of ZnO:TiO2 thin film decreased when the concentration of TiO2 increase. The diffraction peak for all ZnO:TiO2 samples show the p...

Nickel oxide (NiO) nanosheet (NS) array films were successfully grown via a simple immersion technique on the seedless and seed-coated glass substrates. The NiO NS on the seed-coated glass substrate (SC) and the NiO NS on the seedless glass substrate (SL) were annealed at 300 °C. X-ray diffraction pattern revealed the crystallinity of SC film impro...

Titanium dioxide (TiO 2 ) three-dimensional (3D) nanostructure has been prepared and doped with vanadium (V) using a solution immersion method. The resultant material exhibited improved performance in the role of the sensing element in resistive-type humidity sensor. The improvement is attributed to the arrangement of the nanorod structure which ap...

The zinc doped nickel oxide (Zn:NiO) nanostructures with 0 at.% (UD), 1 at.% (1ZNO), and 2 at.% (2ZNO) of Zn concentrations were successfully deposited on the NiO seed-coated glass substrates. The films were successfully produced from two synthesis techniques: the sol-gel spin coating for NiO seed-coated and the solution immersion for the Zn:NiO na...

Lattice strain effects drive a variety of novel functional responses in epitaxial BiFeO3 thin films and have attracted significant interest and attention from researchers in experimental and theoretical studies. However, the difficulty in designing experimental techniques in addition to facing problems in the first principles approach, such as outp...

In this work, the novel utilisation of customised double- and triple-tail sodium bis(3,5,5-trimethyl-1-hexyl) sulphosuccinate (AOT4) and sodium 1,4-bis(neopentyloxy)-3-(neopentyloxycarbonyl)-1,4-dioxobutane-2-silphonate (TC14) surfactants to assist the direct graphene oxide (GO) synthesis via electrochemical exfoliation utilising dimethylacetamide...

Manganese-doped nickel oxide nanosheet array films are successfully prepared on a nickel oxide seed-coated glass substrate by an immersion method. Various annealing temperatures between 300°C and 500°C are applied to the manganese-doped nickel oxide nanosheet array films to study their effect on the properties of nickel oxide, including humidity se...

Zinc ferrite (ZnFe2O4) photocatalysts have been prepared with different types of zinc precursors using the bio-mimetic synthesis method. The kapok fibre (Ceiba pentandra (L.) Gaertn) used as a sacrificial template. The physiochemical of prepared bio-mimetic materials were carried out thoroughly in this work. The FESEM analysis in mimetic zinc ferri...

Titanium dioxide (TiO2) material have received attention due to their performance in optoelectronics especially in light emission diode (LED) devices. The TiO2 nanotubes array (NTAs) film was synthesized by electrochemical anodization method at different anodizing voltages at room temperature. The surface morphology revealed that sample anodized vo...

Transparent conductive films (TCFs) have been widely used as transparent electrodes in nanoelectronic and energy storage devices. An ideal electrode should have high optical transparency, electrical conductivity and carrier mobility to increase the performance and efficiency of devices. Graphene is introduced as a promising new-generation material...

Transparent conductive films (TCFs) have been widely used as transparent electrodes in nanoelectronic and energy storage devices. An ideal electrode should have high optical transparency, electrical conductivity and carrier mobility to increase the performance and efficiency of devices. Graphene is introduced as a promising new-generation material...

This work describes the synthesis of sebacic acid capped silver nanoparticles (SA-AgNPs) by the wet chemical method for the detection of L-Histidine in blood serum and urine samples. The synthesized SA-AgNPs were characterized by several techniques. The obtained particles were spherical in shape and the average diameter was calculated by HR-TEM ima...

Waste cooking palm oil (WCPO) has been utilized as a green carbon source for the synthesization of graphene by double thermal chemical vapor deposition. The WCPO was placed in the first furnace (precursor furnace) whereas nickel was placed in the second furnace (deposition furnace). The deposition temperatures were varied between 850 and 1100 °C. R...