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Abstrak :
Komposit ZrO2/NGP dan ZrO2/graphene dengan masing-masing 5 massa dari NGP dan graphene telah disintesis dengan menggunakan metode sol-gel, dilanjutkan dengan metode kopresipitasi. Sampel tersebut dikarakterisasi dengan X-ray Diffraction XRD , Energy Dispersive X-ray EDX , Transmission Electron Microscopy TEM , Brunauer-Emmett-Teller BET , Fourier Transform Infrared FT-IR , UV-Visible Diffuse Reflectance UV-Vis dan Thermal Gravimetric Analysis TGA dalam rangka untuk menginvestigasi kristal struktur, komposisi atomic, morfologi, luas spesifik permukaan, mode vibrasi, nilai celah energi dan stabilitas panas dari komposit. Aktivitas catalytic dilakukan dengan menggunakan sinar ultraviolet photocatalytic , ultrasonic sonocatalytic dan gabungan antara ultraviolet dengan ultrasonic sonophotocatalytic sebagai sumber iradiasi pada proses degradasi limbah pewarna methylene blue MB . Hasil menunjukan bahwa ZrO2/graphene mampu menghadirkan kemampuan aktivitas catalytic dan adsorpsi yang lebih baik daripada ZrO 2/NGP dan ZrO2 pada proses degradasi MB. Pada aktivitas catalytic, ditunjukan bahwa sonophotocatalytic menghadirkan efisiensi terbagik, diikuti dengan sonocatalytic dan photocatalytic. Sebagai tambahan, efek dari, suhu kalsinasi, derajat keasaman pH , dosis katalis, konsentrasi MB, scavenger spesies aktif dan penggunaan kembali diinvestigasi dan hasilnya akan dibahas. ......ZrO2 NGP and ZrO2 graphene composites with five weight percent 5 wt of NGP and graphene, respectively, where synthesized by sol gel method, followed by coprecipitation. The prepared samples were characterized by X ray Diffraction XRD , Energy Dispersive X ray EDX , Transmission Electron Microscopy TEM , Brunauer Emmett Teller BET , Fourier Transform Infrared FT IR , UV Visible Diffuse Reflectance UV Vis and Thermal Gravimetric Analysis TGA in order to investigate the crystal structure, atomic composition, morphology, specific surface area, vibration modes, bandgap energy value and thermal stability of the samples. The catalytic activities were performed using ultraviolet photocatalytic , ultrasonic sonocatalytic and the combination of ultraviolet and ultrasonic sonophotocatalytic as an irradation source in degrading methylene blue MB dye. The results showed that ZrO2 graphene could exhibit the best catalytic performance and adsorption than ZrO2 NGP and ZrO2 in degrading MB. In the catalytic activity, sonophotocatalytic exhibit the best catalytic performance, followed by sonocatalytic and photocatalytic. In addition, effect of contact time, calcination temperature, pH, catalyst dosage, MB concentration, scavenger of active species and reusability were investigated and the results were discussed.

Abstrak :
Nanokomposit MnFe2O4/NGP dengan variasi 5, 10, dan 15 wt.% digunakan untuk sebagai katalis untuk mendegradasi methylene blue pada proses fotokatalitk dan sonokatalitik. MnFe2O4 dan MnFe2O4/NGP 5, 10, 15 wt.% disintesis dengan menggunakan metode hydrothermal. Impuritas dan fase lain tidak ditemukan pada pengukuran x-ray diffraction (XRD) dan x-ray fluorescence (XRF). Keberadaan NGP terkonfirmasi dari pengukuran XRD, thermogravimetric analysis (TGA), spektroskopi Raman, dan x-ray photoelectron spectroscopy (XPS). Penambahan luas sampel spesifik seiring bertambahnya NGP dikonfirmasi melalui pengukuran Brunauer-Emmet Teller (BET). Morfologi dari MnFe2O4 yang menyerupai persegi dan cenderung berkumpul didapat dari pengukuran transmission electron microscopy (TEM). Katalis memiliki kemampuan degradasi yang lebih baik pada proses photocatalytic dengan cahaya tampak dibanding cahaya UV. Kondisi sistem terbaik dari katalis untuk mendegradasi methylene blue adalah pada dosis katalis 0.2 g/L, konsentrasi H2O2 8 mL, dan pH 13. Penambahan NGP pada MnFe2O4 terbukti meningkatkan kemampuan degradasi methylene blue. Katalis juga terbukti memiliki stabilitas yang tinggi setelah digunakan sebanyak lima kali. Spesies aktif dari katalis pada proses fotokatalitik dan sonokatalitik adalah hidroksil radikal. ......MnFe2O4/NGP nanocomposites with variations of 5, 10, and 15 wt.% were used as catalysts to degrade methylene blue in the photocatalytic and sonocatalytic processes. MnFe2O4 and MnFe2O4/NGP 5, 10, 15 wt.% were synthesized using the hydrothermal method. Impurities and other phases were not found in x-ray diffraction (XRD) and x-ray fluorescence (XRF) measurements. The presence of NGP was confirmed by XRD measurements, thermogravimetric analysis (TGA), Raman spectroscopy, and x-ray photoelectron spectroscopy (XPS). The increase in specific sample area as NGP increases was confirmed by Brunauer-Emmet Teller (BET) measurements. The morphology of MnFe2O4 which resembles a square and tends to congregate was obtained from transmission electron microscopy (TEM) measurements. The catalyst has better degradation ability in photocatalytic processes with visible light than UV light. The best system conditions for the catalyst to degrade methylene blue were at a catalyst dose of 0.2 g / L, 8 mL H2O2 concentration, and a pH of 13. The addition of NGP to MnFe2O4 was proven to increase the degradation ability of methylene blue. The catalyst has also been shown to have high stability after being used five times. The active species of catalyst in photocatalytic and sonocatalytic processes are hydroxyl radicals

Abstrak :
ABSTRAK
Penelitian ini membahas pengaruh penambahan material nanographene platelets NGP dan nanoparticles Ag pada komposit Fe3O4/CuO/ZnO dengan menggunakan metode sol-gel dilanjutkan dengan metode co-precipitation. Komposit yang terbentuk kemudian dikarakterisasi dengan menggunakan X-ray diffraction XRD , Energy-Dispersive X-ray EDX , Thermal Gravimetric Analysis TGA , Fourier Transform Infrared FT-IR , UV-Visible Diffuse Reflectance UV-Vis , UV-Vis Absorbance spectroscopy, Scanning Electron Microscopy SEM dan Transmission Electron Microscopy TEM . Pengujian karakterisasi menunjukkan bahwa material yang disentasis merupakan gabungan dari nanoparticles Ag, Fe3O4, CuO, ZnO, dan NGP, sesuai dengan yang diinginkan. Pengujian aktivitas catalytic photo-, sono-, dan sonophotocatalytic dilakukan dengan menggunakan methylene blue MB sebagai model polutan pada keadaan cair. Penambahan Ag dan NGP menunjukkan peningkatan aktivitas catalytic dibandingkan dengan pure komposit Fe3O4/CuO/ZnO. Pengujian scavengers didapatkan bahwa hole dan hydroxyl radicals merupakan spesies dominan dalam aktivitas catalytic. Terakhir, sampel yang dibuat menunjukkan kestabilitasan dalam degradasi limbah selama 4 kali percobaan berulang reusability , hal tersebut menunjukkan potensi dari material Ag/Fe3O4/CuO/ZnO/NGP komposit sebagai degradasi limbah.

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ABSTRACT
This research discusses the effect of adding nanographene platelets NGP and Ag nanoparticles onto Fe3O4 CuO ZnO composites by using sol gel method followed by simple co precipitation method. The as prepared composites were characterized using X ray diffraction XRD , Energy Dispersive X ray EDX , Thermal Gravimetric Analysis TGA , Fourier Transform Infrared FT IR , UV Visible Diffuse Reflectance UV Vis , UV Vis Absorbance spectroscopy, Scanning Electron Microscopy SEM dan Transmission Electron Microscopy TEM . Characterization tests show that the as prepared samples are combination of desired Ag, Fe3O4, CuO, ZnO, and NGP nanoparticles. The catalytic activity photo , sono , and sonophotocatalytic was performed using methylene blue MB as the pollutant model in aqueous solution. The addition of Ag nanoparticles and NGP showed an increase in catalytic activity compared to pristine Fe3O4 CuO ZnO composites. The scavengers test showed that hole and hydroxyl radicals are the dominant species in catalytic activity. Finally, the Ag Fe3O4 CuO ZnO NGP composite exhibits good catalytic stability in four times cycling processes.