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Abstrak :
Pada penelitian ini, dua jenis graphene graphene dan nanographene platelets NGP dipergunakan sebagai supporting adsorbent dan juga katalis untuk proses degradasi limbah pewarna. Material graphene dan NGP dipergunakan untuk men-support kemampuan adsorpsi dari material nanopartikel Fe3O4. Kemampuan adsorpsi dari nanopartikel Fe3O4 meningkat dengan penambahan material NGP dan graphene. Penambahan material graphene pada Fe3O4 menunjukan kemampuan adsorpsi yang paling baik dibandingkan dengan penambahan material NGP. Material NGP dan graphene juga dipergunakan untuk meningkatkan kemampuan fotokatalitik nanokomposit Fe3O4/ZnO/CuO FZC dibawah penyinaran cahaya ultraviolet UV dan cahaya tampak serta kemampuan sonophotocatalytic dibawah radiasi UV ultrasound US dan cahaya tampak US . Penambahan material graphene menghasilkan kemampuan adsorpsi dan aktivitas fotokatalitik dikarenakan memiliki luasan area yang lebih besar serta oxygen functional group dari material graphene. Penambahan material NGP dan graphene juga mampu menghambat laju rekombinasi elektron dan hole dikarenakan kemampuan graphene dan NGP untuk bertindak sebagai electron acceptor. Hal tersebut berdampak terhadap peningkatan kemampuan aktivitas katalitik dari sampel. Sifat fisis dari seluruh material dianalisis menggunakan X-ray diffractions XRD , energy dispersive X-ray EDX , transmission electron microscope TEM , UV-Vis diffuse reflectance spectroscopy, Fourier transform Infra-red FT-IR spectroscopy Raman spectroscopy, Brunauer ndash;Emmett ndash;Teller BET , differential thermal analysis and thermogravimetric analysis DTA/TGA , vibrating sample magnetometer VSM. ......In this study, two types of Carbon nanographene platelets NGP and graphene has been used as supporting adsorbent and catalyst for waste water removal. Both NGP and graphene were used to support the adsorption ability of Fe3O4 nanoparticles. The adsorption ability of Fe3O4 was increase with the incorporation of NGP and graphene. The incorporation of graphene resulted in the higher adsorption ability of the samples. Moreover, NGP and graphene also used to support the photocatalytic performance under UV and visible light irradiation as well as sonophotocatalytic under UV ultrasound US and visible US of Fe3O4 ZnO CuO FZC nanocomposites. The incorporation of graphene has better adsorption and catalytic performance than the incorporation of NGP due to the higher specific surface area and also the oxygen functional group in graphene materials. The incorporation of NGP and graphene has an ability to prevent recombination electron and hole due to both NGP and graphene could act as electron acceptors. It impacts on the improvement the catalytic performance. The combination of The physical properties of the samples was investigated using X ray diffractions XRD , energy dispersive X ray EDX , transmission electron microscope TEM , UV Vis diffuse reflectance spectroscopy, Fourier transform Infra red FT IR spectroscopy, Raman spectroscopy, Brunauer ndash Emmett ndash Teller BET , differential thermal analysis and thermogravimetric analysis DTA TGA , vibrating sample magnetometer VSM.

Abstrak :
Metode hidrotermal telah diterapkan dalam pembuatan katalis nanokomposit Ag/CeO2 dengan tiga variasi rasio molar katalis nanopartikel CeO2 dan penambahan graphene pada nanokomposit dengan variasi tiga persen berat (wt.%). Kotoran dan fase lain dalam sampel tidak ditemukan dalam pengukuran Difraksi sinar-X (XRD) dan fluoresensi sinar-X (XRF). Keberadaan graphene dikonfirmasi oleh pengukuran Thermal Gravimetric Analysis (TGA) dan Raman Spectroscopy. Luas permukaan spesifik nanokomposit terbesar diperoleh untuk rasio molar CeO2 1:2 dan peningkatan 10wt.% pada graphene berdasarkan hasil pengukuran BET. Tiga jenis proses katalitik yang digunakan untuk mendegradasi Methylene Blue (MB), yaitu sonocatalytic (paparan gelombang ultrasonik), fotokatalitik (paparan sinar tampak dan ultraviolet), dan kombinasi keduanya (sonophotocatalytic). Degradasi maksimum MB diperoleh untuk variasi rasio molar 1:2 dengan 5 wt.% graphene untuk dosis 0,5 g/L dengan konsentrasi MB 20 mg/L pada pH larutan 13 untuk ketiganya. jenis proses katalitik. Mekanisme degradasi maksimum MB dalam proses sonofotokatalitik untuk katalis nanokomposit graphene Ag/CeO2/5 wt.% adalah kontribusi kekosongan oksigen, luas permukaan spesifik, adanya resonansi plasmon permukaan (SPR) dan situs aktif. Spesies aktif lubang yang berperan dalam proses katalitik yang melibatkan cahaya yaitu proses fotokatalitik dan sonofotokatalitik, sedangkan radikal hidroksil merupakan spesies yang berperan aktif dalam proses sonokatalitik.
The hydrothermal method has been applied in the manufacture of Ag/CeO2 nanocomposite catalysts with three variations of the molar ratio of the CeO2 nanoparticle catalyst and the addition of graphene to the nanocomposite with a variation of three percent by weight (wt.%). Impurities and other phases in the sample were not found in X-ray diffraction (XRD) and X-ray fluorescence (XRF) measurements. The existence of graphene was confirmed by Thermal Gravimetric Analysis (TGA) and Raman Spectroscopy measurements. The largest specific surface area of ​​nanocomposite was obtained for CeO2 1:2 molar ratio and 10wt.% increase in graphene based on BET measurement results. Three types of catalytic processes are used to degrade Methylene Blue (MB), namely sonocatalytic (exposure to ultrasonic waves), photocatalytic (exposure to visible and ultraviolet light), and a combination of both (sonophotocatalytic). The maximum degradation of MB was obtained for a variation of the molar ratio of 1:2 with 5 wt.% graphene for a dose of 0.5 g/L with a concentration of MB 20 mg/L at a solution pH of 13 for all three. type of catalytic process. The maximum degradation mechanism of MB in the sonophotocatalytic process for Ag/CeO2/5 wt.% graphene nanocomposite catalyst is the contribution of oxygen vacancies, specific surface area, presence of surface plasmon resonance (SPR) and active sites. Active species of holes that play a role in catalytic processes involving light are photocatalytic and sonophotocatalytic processes, while hydroxyl radicals are species that play an active role in sonocatalytic processes.