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Titanium dioxide (TiO2) has been acknowledged as a promising photocatalyst in environmental remediation including wastewater treatment. In this study, TiO2 nanoparticles either by single or co-doped of iron (Fe) and nitrogen (N) via sol-gel method and calcined at 500 °C for 3 hours. This experiment investigated the performance of mono/co-dopant of TiO2 photocatalyst against methyl orange in aqueous solution under UV light irradiation. The experimental results showed the rate of degradation favored in co-doped TiO2 followed by mono doped TiO2 and pristine TiO2. The photocatalytic reaction followed pseudo first-order kinetics which were rationalized in terms of the Langmuir– Hinshelwood model and provided nearly complete degradation

Titanium dioxide (TiO2) has been acknowledged as a promising photocatalyst in environmental remediation including wastewater treatment. In this study, TiO2 nanoparticles either by single or co-doped of iron (Fe) and nitrogen (N) via sol-gel method and calcined at 500 °C for 3 hours. This experiment investigated the performance of mono/co-dopant of TiO2 photocatalyst against methyl orange in aqueous solution under UV light irradiation. The experimental results showed the rate of degradation favored in co-doped TiO2 followed by mono doped TiO2 and pristine TiO2. The photocatalytic reaction followed pseudo first-order kinetics which were rationalized in terms of the Langmuir– Hinshelwood model and provided nearly complete degradation

As oil exploration and production activities have risen globally, water contamination from oil spills and the discharge of other oily wastewaters has emerged as one of the primary environmental concerns. Thus, Kapok fiber is considered in this study as it is known as one of the most effective method for cleaning up and collecting oil spills where Kapok is a natural cellulosic fiber with unique characteristics. A critical investigation was conducted to study the potential of kapok fiber as sorbent material, also analyze the surface properties of kapok fiber for the ability of kapok fiber to absorb oil and investigate the sorption mechanisms of kapok fiber. Therefore, the surface properties of kapok fiber were analyzed using SEM, FTIR, TGA and contact angle. To investigate the selectivity nature and the sorption capacity of 5 g kapok fiber, different types of oil and different apparent viscosity were used. The types of oil used are gear oil (low viscosity), vegetable oil-based cooking oil (medium viscosity) and waste oil (high viscosity). Kapok fiber was able to absorb all types of oil, with wasted oil absorbing the most about 17.88 g.g-1. Scanning electron microscopy (SEM) was used to examine the morphology of raw kapok fiber. In this study, kapok fiber was shown to have a porous hollow lumen structure and a waxy coating on the surface. Other than that, for the contact angle analysis, kapok fiber had high water contact angle up to 130˚. The water droplet was stood on the kapok fibers surfaces before and after absorption with contact angles ranging from 130˚ to 145˚. In contrast, the oil droplet had disappeared from the surfaces of kapok fiber within a few seconds

A particular type of steel has a higher concentration of carbon than other types of steel called carbon steel. This study focused on the electrodeposition coating of Nickel Silicon Carbide (Ni-SiC) composite coating at 50 oC. In this study, medium carbon steel was used as a substrate. 25 g/l SiC was used during the deposition. The carbon steel was acted as the cathode and the carbon rod as an anode during electrodeposition. The coated sample was heat-treated at 350 OC for 1 hour. Scanning Electron Microscope (SEM) was used to analyze the surface morphology and microstructure of the coated and heat-treated sample before and after the wear test. The coated sample's element composition and phase distribution are determined using the Energy Dispersive Spectroscopy (EDS) and X-Ray Diffraction (XRD). To identify the hardness of the composite coating, Vickers micro-hardness test was used on the surface of the sample with 100g load in 10 seconds with ten indentations. Weight loss method was conducted to determine the average wear resistance of the sample. The wear behavior of the Ni-SiC was evaluated using the weight loss method with 3 g/l alumina as the abrasive material. The results showed that the heat-treated coating had higher wear resistance than the without heat treatment. The findings also showed that the sample with the heat-treatment process had a higher hardness. This proved that the heat-treated sample had the best wear behavior and hardness value compared to without heat treatment due to denser coating produced

As oil exploration and production activities have risen globally, water contamination from oil spills and the discharge of other oily wastewaters has emerged as one of the primary environmental concerns. Thus, Kapok fiber is considered in this study as it is known as one of the most effective method for cleaning up and collecting oil spills where Kapok is a natural cellulosic fiber with unique characteristics. A critical investigation was conducted to study the potential of kapok fiber as sorbent material, also analyze the surface properties of kapok fiber for the ability of kapok fiber to absorb oil and investigate the sorption mechanisms of kapok fiber. Therefore, the surface properties of kapok fiber were analyzed using SEM, FTIR, TGA and contact angle. To investigate the selectivity nature and the sorption capacity of 5 g kapok fiber, different types of oil and different apparent viscosity were used. The types of oil used are gear oil (low viscosity), vegetable oil-based cooking oil (medium viscosity) and waste oil (high viscosity). Kapok fiber was able to absorb all types of oil, with wasted oil absorbing the most about 17.88 g.g-1. Scanning electron microscopy (SEM) was used to examine the morphology of raw kapok fiber. In this study, kapok fiber was shown to have a porous hollow lumen structure and a waxy coating on the surface. Other than that, for the contact angle analysis, kapok fiber had high water contact angle up to 130˚. The water droplet was stood on the kapok fibers surfaces before and after absorption with contact angles ranging from 130˚ to 145˚. In contrast, the oil droplet had disappeared from the surfaces of kapok fiber within a few seconds

Natural sorbents have several benefits, including high sorption capacity, superior biodegradability, and low cost. Kapok is one of the natural fibers that can be used as absorbent material. These distinctive qualities give kapok fibers greater oil sorption capacity than other oil sorbents currently on the market. However, it is difficult to hold oil properly due to its waxy coating and smooth fiber surface. Thus, in this study, the rough surface fiber has been coated using ZnO via the hydrothermal method. Considering that ZnO is instinctually hydrophilic, this modification of the fiber compounds increases the adsorption of oil in fiber. The surface morphology interaction has been proven with an experiment using a scanning electron microscope (SEM) for morphology investigation, Fourier-transform infrared spectroscopy (FTIR) for identifying organic or inorganic materials, and physical interaction (contact angle analysis). The results obtained display a significant difference between modified kapok fiber with ZnO and raw kapok fiber. The FTIR analysis shows that the modified kapok exhibits the peak's level of intensity at 3268.88 cm-1 (stretching vibration peak of surface –OH decreases obviously as compared with that of raw kapok fiber, an absorption peak (symmetric stretching vibration of Zn–O–Zn) is observed at 652.28 cm-1. These results suggested that the whole sum of –OH was diminished, and hydrophobic ZnO nanoparticles were developed on the kapok fiber's surface. A surface morphology analysis using SEM shows that ZnO particles are present on the kapok fiber surface while comparing it to the raw kapok. Modified kapok shows a higher contact angle (138°) compared to raw kapok (125.5°). This can conclude that the kapok fiber modification was successfully achieved using the hydrothermal method

A particular type of steel has a higher concentration of carbon than other types of steel called carbon steel. This study focused on the electrodeposition coating of Nickel Silicon Carbide (Ni-SiC) composite coating at 50 oC. In this study, medium carbon steel was used as a substrate. 25 g/l SiC was used during the deposition. The carbon steel was acted as the cathode and the carbon rod as an anode during electrodeposition. The coated sample was heat-treated at 350 OC for 1 hour. Scanning Electron Microscope (SEM) was used to analyze the surface morphology and microstructure of the coated and heat-treated sample before and after the wear test. The coated sample's element composition and phase distribution are determined using the Energy Dispersive Spectroscopy (EDS) and X-Ray Diffraction (XRD). To identify the hardness of the composite coating, Vickers micro-hardness test was used on the surface of the sample with 100g load in 10 seconds with ten indentations. Weight loss method was conducted to determine the average wear resistance of the sample. The wear behavior of the Ni-SiC was evaluated using the weight loss method with 3 g/l alumina as the abrasive material. The results showed that the heat-treated coating had higher wear resistance than the without heat treatment. The findings also showed that the sample with the heat-treatment process had a higher hardness. This proved that the heat-treated sample had the best wear behavior and hardness value compared to without heat treatment due to denser coating produced

Zinc Oxide (ZnO) is an inorganic compound and it is doped with aluminum to increase its capabilities. Aluminum Zinc Oxide (AZO) thin films are semiconductor materials that have band gap energy of 3.3eV. Various method of deposition have been study to growth AZO thin films. It has been extensively use in solar cell application, display application, gas sensing purposes, and thin film transistors (TFTs). In this work, sol gel method and spin coating was used to deposited AZO thin films. The ZnO sol-gel were synthesized using zinc acetate dihydrate as precursor, isopropanol as solvent, diethanolamine as sol stabilizer, and distilled water as oxidation agent. Then, synthesized ZnO were doped with different mole ratio of aluminum nitrate nanohydrate to produced AZO. The glass substrate was used as substrate and AZO thin films were then calcinated at 300°C and 500°C. The characterization of AZO thin film were done using X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), Ultraviolet-visible spectroscopy (UV-Vis), Field Emission Scanning Electron Microscope (FESEM), and Energy Dispersive X-ray spectroscopy (EDX). The XRD results show that the ZnO with hexagonal wurtzite-type structure and temperature does have effect on the film intensity which related to crystallinity of thin films. Through AFM analysis, the value of RMS decreases from 3.018 nm to 2.240 nm as the temperature increases. Meanwhile, from UV-Vis result, it can be seen that AZO thin film have a high transmittance percentage above 90% after wavelength 400 nm with band gap value of 3.3 eV. FESEM image show that the grain boundary of AZO decrease with both parameter (mole ratio and calcinations temperature). Both parameters do have effect on AZO thin film. EDX analysis shows that there are existence of zinc, oxide, and aluminum.