Ardiansyah Taufik

Preparation, Characterization and Photocatalytic Activity of Multifunctional Fe3O4/ZnO/CuO Hybrid Nanoparticles

A series of copper oxide supported on Fe3O4/ZnO with molar ratio of Fe3O4:ZnO:CuO varies from 1:1:1 to 1:1:5 were prepared by sol-gel method. X-ray diffraction, field emission scanning electron microscope, energy-dispersive X-ray spectroscopy, UV-visible diffuse reflectance spectroscopy and vibrating sample magnetometer were used to characterize the as prepared Fe3O4/ZnO/CuO hybrid nanoparticles. The results show that Fe3O4/ZnO/CuO hybrid nanoparticles consist of cubic spinel Fe3O4, hexagonal wurtzite ZnO and monoclinic CuO. All prepared samples show ferromagnetic behavior. The photocatalytic activities of these hybrid nanoparticles under visible light irradiation were evaluated by the degradation of malachite green. The results revealed that hybrid nanoparticles exhibited higher photocatalytic activities than pure nanoparticles.

Synthesis of iron(II,III) oxide/zinc oxide/copper(II) oxide (Fe3O4/ZnO/CuO) nanocomposites and their photosonocatalytic property for organic dye removal

A facile sol-gel method was adopted to synthesize iron(II,III) oxide/zinc oxide/copper(II) oxide (Fe3O4/ZnO/CuO) nanocomposites with various CuO loadings at a low temperature. The prepared nanocomposites were characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, UV-Vis spectroscopy, vibrating sample magnetometry, and Brunauer-Emmett-Teller (BET) surface area analyses. The photosonocatalytic properties of the nanocomposites were tested by methylene blue removal in aqueous solutions under the combination of UV or visible light and ultrasound. The catalyst with the lowest CuO loading exhibited the highest photosonocatalytic performance under UV light, while the fastest degradation under visible light was achieved at the highest CuO loading. Overall, the photosonocatalytic process with light and ultrasound irradiation led to more complete degradation compared to using light alone. According to the experiments performed with radical scavengers, the holes and OH radicals are the dominant oxidative species. The nanocomposites can be easily separated from the treated solution using an external magnetic field, and the samples remain very stable after 4 cycles. These results indicate that these materials have great potential for treating organic pollutants in wastewaters.

Comparison of Catalytic Activities for Sonocatalytic, Photocatalytic and Sonophotocatalytic Degradation of Methylene Blue in the Presence of Magnetic Fe3O4/CuO/ZnO Nanocomposites

Fe3O4/CuO/ZnO nanocomposites with different molar ratio were synthesized using sol-gel method. The as-synthesized samples were characterized by X-ray diffraction (XRD), UV-visible spectroscopy, BET surface area analyszer, and Electron Spin Resonance (ESR). The sonocatalytic-photocatalytic-sonophotocatalytic activity of as-synthesized samples was investigated based on methylene blue degradation. Moreover, the role of active species was investigated using scavenger technique. The results showed that hole plays an important key role in sono-photo-sonophotocatalytic degradation of methylene blue.

Enhanced UV Photocatalytic Performance of Magnetic Fe3O4/CuO/ZnO/NGP Nanocomposites

Fe3O4/CuO/ZnO/nanographene platelets (Fe3O4/CuO/ZnO/NGP) with varied ZnO loadings have been synthesized using a sol-gel method followed by hydrothermal method. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) confirmed the formation of the Fe3O4/CuO/ZnO/NGP composites. All of the samples showed the presence of graphene nanoplatelets incorporating Fe3O4, CuO and ZnO structures and exhibited ferromagnetic behavior at room temperature. The composites showed photocatalytic activity under UV irradiation, which was used to affect the degradation of methylene blue. The Fe3O4/CuO/ZnO/NGP composites showed superior photocatalytic activity than the Fe3O4/CuO/ZnO materials.

Ag/Ag2O/TiO2 nanocomposites: microwave-assisted synthesis, characterization, and photosonocatalytic activities

Nanocomposites of Ag/Ag2O/TiO2 were synthesized using a microwave-assisted method. As-prepared samples were systematically characterized by X-ray diffraction, electron spin resonance, and diffuse reflectance spectroscopy. The photosonocatalytic performance was investigated under both UV and visible light and ultrasonic irradiation in terms of degradation of methylene blue (MB) dye in aqueous solution. Compared with the pure TiO2 nanoparticles and Ag/Ag2O nanocomposites, the Ag/Ag2O/TiO2 nanocomposites presented more responsive photosonocatalytic activity in the wide range of light wavelengths. It is believed that defect states in TiO2 nanoparticles, which were observed by ESR measurements, played an important role in trapping the charge carrier in the photosonocatalytic process. In addition, the degradation process was studied in terms of the influence of several experimental parameters, and a reasonable mechanism of photosonocatalysis with Ag/Ag2O/TiO2 nanocomposites was proposed by correlating the active radical species involved with the physical properties of the as-synthesized samples.

The Role of Annealing Temperature in Photocatalytic Performance of Fe3O4/SnO2 nanocomposites

In this work, SnO2 nanoparticles with the variation of annealing temperature (400°C-800°C) were used as photocatalyst for remove organic dye from the aqueous solution. SnO2 nanoparticles were synthesized using sol-gel method. For enhancing the stability and the photocatalytic activity of the samples, magnetite materials (Fe3O4) were combined with SnO2 nanoparticles. The prepared samples characterized by X-ray Diffraction (XRD). The X-ray diffraction shows tetragonal structure of SnO2 and cubic spinel of Fe3O4 as the components of the prepared nanocomposites. The photocatalytic activity of the samples was studied using Methylene Blue (MB) as a model organic pollutant. The photocatalytic degradation of MB by SnO2 and Fe3O4 nanocomposites under UV light irradiation was examined by varying the operational parameters such as catalyst dosage and scavengers. Among the variation annealing temperature of SnO2 nanoparticles, the 700°C annealing temperature of SnO2 showed the highest photocatalytic activity. The repeatability of photocatalytic activity was also tested.

Sono- and photocatalytic activities of SnO2 nanoparticles for degradation of cationic and anionic dyes

The current research work focuses on the catalytic activity of SnO2 nanoparticles (NPs) against degradation of both cationic dye (methylene blue) and anionic dye (Congo-red). SnO2 NPs were synthesized under the sol-gel method and were characterized by performing X-ray diffraction, Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM) Brunauer-Emmet-Teller (BET) surface area analysis and UV-Vis spectroscopy. The results demonstrate that SnO2 NPs has well crystalline structure with the crystallite size of 44 nm. The degradation of dyes was studied under ambient temperature using ultrasonicator and UV light, respectively. The sono- and photocatalytic activities of SnO2 NPs on dyes were analyzed by measuring the change in absorbance of dyes under UV-spectrophotometer. The degradation of the organic dyes has been calculated by monitoring the degradation in the concentration of the dyes before and after irradiation of ultrasonic and light, respectively. The influence of other p...

The influence of two-type graphene material on photocatalytic activity of ZrO2 nanoparticles under UV light irradiation

In this study, ZrO2/nanographene platelets (NGP) and ZrO2/graphene composites were fabricated by depositing ZrO2 nanoparticles onto nanographene platelets and graphene surfaces to develop photocatalysts. ZrO2/NGP and ZrO2/graphene were successfully synthesized using the co-precipitation method. The physicochemical characteristics were studied through X-ray diffraction, transmission electron microscope, energy dispersive X-ray analysis, Brunauer-Emmett-Teller method and infrared absorption. The X-ray diffraction results revealed that the ZrO2 nanoparticles have a typical tetragonal structure and the average crystallite size was found to be approximately 13 nm by using the Debye-Scherrer’s equation. The results are also confirmed by TEM measurements. The photocatalytic activity of ZrO2/NGP and ZrO2/graphene composites was evaluated by degrading methylene blue under UV light irradiation which confirmed that ZrO2/graphene composites have better catalytic performance than ZrO2/NGP composites and pure ZrO2 nanoparticles. An effort has been made to correlate the physicochemical characteristic of ZrO2/NGP and ZrO2/graphene composites to the rate of photocatalytic degradation of methylene blue. The results demonstrated that graphene incorporation in ZrO2 nanoparticles could greatly improve the photocatalytic activity. In addition, the influence of catalyst dosage, initial concentration, and scavengers of reactive species on the photocatalytic activity was investigated. Moreover, the composites were found to be reusable photocatalyst.In this study, ZrO2/nanographene platelets (NGP) and ZrO2/graphene composites were fabricated by depositing ZrO2 nanoparticles onto nanographene platelets and graphene surfaces to develop photocatalysts. ZrO2/NGP and ZrO2/graphene were successfully synthesized using the co-precipitation method. The physicochemical characteristics were studied through X-ray diffraction, transmission electron microscope, energy dispersive X-ray analysis, Brunauer-Emmett-Teller method and infrared absorption. The X-ray diffraction results revealed that the ZrO2 nanoparticles have a typical tetragonal structure and the average crystallite size was found to be approximately 13 nm by using the Debye-Scherrer’s equation. The results are also confirmed by TEM measurements. The photocatalytic activity of ZrO2/NGP and ZrO2/graphene composites was evaluated by degrading methylene blue under UV light irradiation which confirmed that ZrO2/graphene composites have better catalytic performance than ZrO2/NGP composites and pure ZrO2 nano...

Photocatalytic, sonocatalytic, and photosonocatalytic of Fe3O4/CuO/ZnO nanocomposites with addition of 2 different types of carbon

A nanocomposite catalyst containing zinc oxide (ZnO), copper oxide (CuO), iron oxide (Fe3O4) and graphene was synthesized using a combined sol-gel/hydrothermal method in which we used two different types of graphene such as NGP and graphene. The as-synthesized samples were characterized by X-ray diffraction (XRD), energy dispersive X-ray (EDX), transmission electron microscopy (TEM), Fourier transform infra-red (FTIR) and vibrating sample magnetometer (VSM). We evaluated the photocatalysis, sonocatalysis, and photosonocatalysis of Fe3O4/CuO/ZnO, Fe3O4/CuOZnO/NGP and Fe3O4/CuO/ZnO/Graphene on the degradation of Methylene Blue (MB) and found that the Fe3O4/CuO/ZnO/Graphene exhibits catalytic activity higher than Fe3O4/CuO/ZnO/NGP and Fe3O4/CuO/ZnO. The effect of various scavengers has also been studied. Furthermore, all prepared nanocomposites could be used as a convenient recyclable catalyst because of their magnetic properties.

Synergy effect in sonodegradation of organic dye using graphene based magnetite composite materials

Owing to the unique physical properties, nanographene platelets could act as a good recombination inhibitor for functional materials. In this study, various concentrations of nanographene platelets are introduced to ferromagnetic Fe3O4 nanoparticles to remove methylene blue in aqueous solution under ultrasonic irradiation. The coupling of nanographene platelets with Fe3O4 nanoparticles is formed using hydrothermal method. Compared to pure Fe3O4 nanoparticles, Fe3O4–nanographene platelets (Fe3O4–NGP) composites exhibited higher catalytic efficiency for methylene blue removal under ultrasonic irradiation. The catalytic efficiency increase with increasing nanographene platelets loading from 1 wt.% until 5 wt% and further decreased. From the scavenger technique, it is revealed that hole plays an important key role in sonocatalytic processes. The degradation efficiency decreased only 12% after 4 cycled.