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Abstrak :
Kebutuhan air bersih meningkat seiring dengan bertambahnya populasi penduduk, namun kebutuhan air bersih tercemar karena kontaminasi limbah cair salah satunya akibat zat warna, proses degradasi zat warna sangat perlu dilakukan dalam upaya reduksi pencemaran air, Salah satu metode yang dapat dilakukan adalah fotodegradasi. Pada penelitian ini dilakukan fotodegradasi zat warna Methylene Blue melalui proses fotokatalitik dengan nanokatalis heterostruktur Au-TiO2. Sintesis TiO2 Nanosheet yang melalui metode Hidrotermal, didapatkan nilai celah pita sekitar 3.38 eV untuk struktur Anatase dengan panjang rata-rata 28 nm dan ketebalan 3.05 nm. Au Nanorod disintesis melalui metode Seeds Mediated Growth dengan variasi penambahan AgNO3 menghasilkan profil fenomena resonansi permukaan plasmon (SPR) yang berbeda dengan serapan paling tinggi pada 800 nm dan aspect ratio yang meningkat dari 3.7-4.5. Integrasi dilakukan dengan metode Ligand Exchange dan pengaturan pH. Laju kinetika tertinggi dari hasil fotodegradasi dicapai oleh Au-TiO2 yang diintegrasi melalui metode Ligand Exchange sebesar 0.1029 min-1. ...... Demand of clean water increase along with an increase in population, but the presence of organic dyes has become one of the reasons of water contaminant and becoming an environmental problem, the treatment of dye removal nowadays is become very necessary to reduce water pollution. The most efficient and reliable method to degraded organic dyes is using photodegradation method. In this research, we report the result of Methylene Blue photodegradation through the photocatalytic process using Au-TiO2 heterostructured nanocatalysts. TiO2 nanosheets was synthesized through hydrothermal method, the band gap value is 3.38 eV for Anatase structures with an average length of 28 nm and thickness of 3.05 nm. Gold nanorods was synthesized through Seeds Mediated Growth method with variations in the addition of AgNO3. Show a different profile of the Surface Plasmon Resonance (SPR) phenomenon with the highest absorption at 800 nm and an increased aspect ratio from 3.7-4.5. Integration of Au-TiO2 was done by the Ligand Exchange Method and pH control. The high kinetic rate was achieved from Au-TiO2 nanocatalyst done by the Ligand Exchange Method with 0.1029 min-1.

Abstrak :
The photocatalytic degradation of methylcyclohexane (MCH) in two phases (aqueous and vapor) was examined using modified titania that was immobilized on pumice and performed in the system of a specific condition. The photodegradation system that used a particular configuration reactor and modified catalyst could facilitate the two-phase photodegradation of MCH simultaneously. The photocatalyst was prepared by the mechanical mixing of urea and TiO2 P25 with mass ratios of 1:3 and 2:3, respectively and then calcined at 350 and 450oC. This modified photocatalyst was then immobilized on pumice and finally used for the photodegradation of MCH. The Infrared spectra studies revealed that modified titania with urea successfully incorporated a non-metal dopant within the TiO2 lattice. The catalyst that spread evenly across the surface of the pumice can be seen from Scanning Electron Microscope (SEM) characterization. The loading of 7.5% mass photocatalyst that immobilized on pumice degraded MCH in two-phases simultaneously during a 120 minute period and can be considered the optimum condition.

Abstrak :
The photocatalytic degradation of methylcyclohexane (MCH) in two phases (aqueous and vapor) was examined using modified titania that was immobilized on pumice and performed in the system of a specific condition. The photodegradation system that used a particular configuration reactor and modified catalyst could facilitate the two-phase photodegradation of MCH simultaneously. The photocatalyst was prepared by the mechanical mixing of urea and TiO2 P25 with mass ratios of 1:3 and 2:3, respectively and then calcined at 350 and 450oC. This modified photocatalyst was then immobilized on pumice and finally used for the photodegradation of MCH. The Infrared spectra studies revealed that modified titania with urea successfully incorporated a non-metal dopant within the TiO2 lattice. The catalyst that spread evenly across the surface of the pumice can be seen from Scanning Electron Microscope (SEM) characterization. The loading of 7.5% mass photocatalyst that immobilized on pumice degraded MCH in two-phases simultaneously during a 120 minute period and can be considered the optimum condition.

Abstrak :
TiO2 merupakan material yang memiliki daya oksidasi yang tinggi. Namun, oleh karena bandgap-nya yang lebar, aktivitas fotokatalisis TiO2 terbatas pada iradiasi UV. Pada penelitian ini, nanokomposit TiO2/CeFeO3 disintesis melalui metode green synthesis dengan memanfaatkan ekstrak daun Artemisia vulgaris (EDAV) sebagai sumber metabolit sekunder. Keberadaan metabolit sekunder dalam EDAV dikonfirmasi melalui uji fitokimia kualitatif dan FTIR. TiO2/CeFeO3 dikarakterisasi menggunakan FTIR, XRD, UV-Vis DRS, dan TEM. Spektra FTIR mengonfirmasi seluruh gugus fungsi yang mungkin terdapat pada TiO2/CeFeO3. Difraktogram nanokomposit TiO2/CeFeO3 menunjukkan puncak difraksi gabungan dari TiO2 dan CeFeO3 yang disertai sedikit pergeseran nilai difraksi. Berdasarkan karakterisasi menggunakan UV-Vis DRS, teramati penurunan energi bandgap TiO2 yang semula 3,25 eV menjadi 2,75 eV setelah dimodifikasi oleh CeFeO3 menjadi TiO2/CeFeO3. Hasil TEM menunjukkan bahwa TiO2/CeFeO3 memiliki partikel yang berbentuk sferis dengan diameter rata-rata sebesar 23,06,3 nm. Aktivitas fotokatalisis diukur berdasarkan kemampuan mendegradasi zat warna malachite green (MG). Dosis optimum TiO2/CeFeO3 dan aktivitas fotokatalisis dari TiO2 dan CeFeO3 juga diselidiki pada penelitian ini. Pada dosis optimum, TiO2/CeFeO3 mampu mendegradasi 93,53% MG, sedangkan TiO2 dan CeFeO3 secara berturut-turut memiliki efisiensi degradasi sebesar 59,96% dan 81,16%. Reaksi fotodegradasi malachite green mengikuti kinetika pseudo orde satu dengan nilai konstanta laju sebesar 2,14x10-2 min-1 untuk TiO2/CeFeO3. ......TiO2 possesses high oxidizing property. However, due to its wide bandgap, TiO2 photocatalytic activity is limited to UV irradiation. In this research, TiO2/CeFeO3 nancomposite was synthesized through green synthesis method utilizing Artemisia vulgaris leaves extract as a source of secondary metabolites. The presence of secondary metabolites was confirmed by qualitative phytochemical screening and FTIR. TiO2/CeFeO3 was characterized using FTIR, XRD, UV-Vis DRS, and TEM. FTIR spectra confirmed all functional groups presence in TiO2/CeFeO3. TiO2/CeFeO3 diffractogram showed a combined diffraction peaks of TiO2 and CeFeO3 with a slight shift. According to UV-Vis DRS characterization, a reduction in TiO2 bandgap energy from 3.25 eV to 2.75 eV was observed after being modified by CeFeO3 into TiO2/CeFeO3. TEM images shows that TiO2/CeFeO3 has a spherical-shape particles with average diameter of 23.06.3 nm. Photocatalytic activity was measured by the degradation percentage of MG. The optimum doses for TiO2/CeFeO3 and photocatalytic activity of TiO2 and CeFeO3 was also investigated in this work. At optimum dose, TiO2/CeFeO3 able to degrade 93.53% of MG, while TiO2 and CeFeO3 have degradation efficiency of 59.96% and 81.16% respectively. Malachite green photodegradation reaction followed pseudo-first order kinetics with a rate constant of 2.14x10-2 min-1 for TiO2/CeFeO3.

Abstrak :
Perkembangan metode sintesis nanopartikel merupakan salah satu bidang yang menarik minat banyak peneliti. Salah satunya metode antarfasa cair-cair. Sintesis ini dilakukan dengan pendekatan yang ramah lingkungan karena memanfaatkan ekstrak tanaman. Daun kelor merupakan salah satu tanaman yang memiliki metabolid sekunder. Penelitian ini bertujuan untuk mensisntesis nanokomposit ZnO-Co3O4 menggunakan ekstrak daun kelor Moringa oliefera dari sistem duafasa heksana ndash;air dan aktivitas fotodegredasi Methylene Blue. Nanokomposit ZnO-Co3O4 hasil sintesis selanjutnya dikarakterisasi menggunakan UV-Vis-DRS, Spektrofotometer FTIR, TEM, SEM-EDX, XRD dan PSA untuk mngetahui morfologi dan struktur kristal dari nanokomposit tersebut. Nilai band-gap nanokomposit ZnO-Co3O4 sebesar 2,3 eV dengan distribusi ukuran partikel sekitar 86,98 nm dengan pengukuran PSA. Morfologi menggunakan SEM memperlihatkan bulatan kecil-kecil. Pada bilangan gelombang 479,9; 591,0; dan 675,0 cm-1 dari spectra FTIR memperlihatkan vibrasi Zn-O, Co-O menandakan terbentuknya nanokomposit ZnO-Co3O4. ZnO-Co3O4 aktivitas fotodegradasi terhadap MB di bawah sinar visible sebesar 99,0 selama 120 menit.

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The development of nanoparticle synthesis method is one of the fields that attract many researchers. One of them is liquid liquid phase method.This method is friendly in environmental because it uses plant extract. Moringa leaf is one of the plants that has secondary metabolite. This study aims to synthesize ZnO Co3O4 nanocomposites using Moringa oliefera leaf extract from hexane water two phases system and photodegredation activity of Methylene Blue. The synthesis of ZnO Co3O4 nanocomposites are further characterized using UV Vis DRS, FTIR Spectrophotometer, TEM, SEM EDX, XRD and PSA to determine the morphology and crystal structure of the nanocomposite. The ZnO Co3O4 nanocomposite band gap value is 2.3 eV with a particle size distribution about 86.98 nm using PSA. The morphology of nanocomposite shows small spheres. The FTIR spectra exhibites vibration Zn O, Co O signaling the formation of ZnO Co3O4 nanocomposites at wave number 479.9 591.0 and 675,0 cm 1 respectively. ZnO Co3O4 photodegradation activity against methylene blue under visible light is 99.0 for 120 minutes.

Abstrak :
A magnetic Fe3O4@ZnO nanocomposite (NC) was successfully synthesized by a wet milling method using a high energy milling (HEM) machine. The magnetic Fe3O4@ZnO NC was characterized by an X-ray Diffractometer (XRD), scanning and transmission electron microscopes (SEM and TEM), and a vibrating sample magnetometer (VSM). X-ray diffraction results show that Fe3O4@ZnO NC consisted of ZnO and Fe3O4 phases. The microstructure analysis indicated that Fe3O4@ZnO NC presented a ZnO shell wrapped around the surface of a magnetic Fe3O4 surface. The average diameter of the aggregated Fe3O4 nanoparticle (NP) is 20 nm, while that of Fe3O4@ZnO NCs is nearly 30 nm. The Fe3O4 NP and Fe3O4@ZnO NC show typical superparamagnetic behavior with low coercivity. The saturation magnetization (Ms) of Fe3O4 NP was measured at about 66.26emu.g-1 and then declined to 34.79emu.g-1 after being encapsulated with a ZnO shell. The photoactivities of the Fe3O4@ZnO NC under UV irradiation were quantified by the degradation of a methylene blue (MB) dye solution. The result reveals that the photodegradation efficiency of Fe3O4@ZnO NC is favorable at pH neutral (pH = 7) reaching 100%. By increasing the MB dye concentration from 10 ppm to 40 ppm, the photodegradation efficiency decreases from 100% to 52%. The Fe3O4@ZnO NC can be easily collected by an external magnet. The magnetic Fe3O4@ZnO NC could be extended to various potential applications, such as purification processes, catalysis, separation, and photodegradation.

Abstrak :
Kombinasi proses fotodegradasi dan biodegradasi untuk eliminasi limbah fenol pada skala bench telah diinvestigasi. Fenol yang digunakan adalah fenol sintetis (konsentrasi awal 10 mg/L). Kinerja fotoreaktor diketahui paling baik pada sistem aliran continuous dengan menggunakan komposit TiO2-Batu Apung. Fotoreaktor sendiri dapat mendegradasi 34 L limbah fenol hingga konsentrasi 7,6 mg/L dalam waktu 3 jam. Kinerja bioreaktor sangat dipengaruhi oleh nutrisi bakteri, baik pada saat pengembangbiakan maupun saat uji dilakukan di reaktor. Nutrisi terbaik bagi Acinetobacter baumannii adalah kompos matang. Bioreaktor sendiri mampu mendegradasi 90 L limbah hingga konsentrasi 1,1 mg/L dalam waktu 14 jam. Di samping itu, susunan foto-bio-reaktor menunjukkan hasil uji degradasi fenol yang lebih baik bila dibandingkan dengan susunan bio-foto-reaktor ditinjau dari persentase degradasi fenol total, dimana kombinasi foto-bio-reaktor mampu mendegradasi hingga 87% fenol dengan volume total 124 L dalam waktu 17 jam.

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Combination process of photodegradation and biodegradation to eliminate phenol in bench scale has been investigated. Synthetic phenol was used within 10 mg/L. Photoreactor showed best performance in continuous system using TiO2 – Pumice composite. Photoreactor itself could reduce 34 L phenol to the concentration of 7,6 mg/L within 3 hours. At the other side, bioreactor performance highly influence by bacteria nutriotion. The best nutrition for Acinetobacter baumannii was cooked-compost. Bioreactor itself could reduce 90 L phenol to the concentration of 1,1 mg/L within 14 hours. Photo-Bio-Reactor showed best performance compared to Bio-Photo-Reactor based on percentage of total phenol degradation, where photo-bio-reactor could eliminate phenol up to 87% with total volume 124 L with in 17 hours.

Abstrak :
Nanokomposit selulosa asetat dibuat melalui dua tahapan, yaitu pembuatan TiO2-organoclay dan pembuatan nanokomposit. Sebagai kontrol juga disintesis nanokomposit tanpa penambahan TiO2 dan nanokomposit selulosa asetat. Organoclay disintesis dalam empat tahapan sintesis yaitu purifikasi bentonit, penyeragaman kation bentonit, sintesis TiO2-MMT dan sintesis TiO2-organoclay. Nanokomposit yang dibuat diberikan penambahan variasi persen berat TiO2- organoclay sebanyak 0%, 1%, 3%, 5% dan 7%. Nanokomposit hasil sintesis diuji kemampuan fotodegradasinya pada penyinaran dengan lampu UV dan lampu LED konvensional. Penyinaran dengan UV menunjukkan persentase pengurangan berat yang paling besar dibandingkan dengan lampu LED konvensional dan tanpa penyinaran cahaya. Pada komposit dengan penambahan 7% berat TiO2 pada hari ke-6 diperoleh persentase pengurangan berat yaitu sebesar 5,60 % untuk penyinaran dengan lampu UV, 1,38 % untuk penyinaran dengan lampu LED konvensional, dan 0,46 % untuk tanpa penyinaran cahaya. ......Celulose acetate nanocomposite was fabricated in two steps synthesis as follows: synthesis of TiO2-organoclay and synthesis of nanocomposite. As control variable there are synthesized nanocomposite without TiO2 and cellulose acetate nanocomposite. Organoclay are synthesized in four steps synthesis there are: bentonite purification, uniformity of bentonite cation, synthesis of TiO2-MMT and synthesis of TiO2-organoclay. Synthesized nanocomposite are contain 0%, 1%, 3%, 5% and 7% TiO2-organoclay (w/w). Nanocomposite are tested in photodegradataion capacity with uv lamp and LED conventional lamp radiation. Radiation with uv light show bigger percentage of weight reduction than radiation with LED conventional lamp and without light radiation. In the composite with the addition of 7 wt% TiO2 on the 6th day gained weight percentage reduction in the amount of 5.60% for irradiation with UV light, 1.38% for irradiation with conventional LED lamps, and 0.46% for without light irradiation.

Abstrak :
ABSTRACT
Pada penelitian ini, sintesis nanopartikel ZnO, nanopartikel SmMnO3, dan nanokomposit ZnO/SmMnO3 secara green synthesis berhasil dilakukan menggunakan ekstrak daun pulai (Alstonia scholaris). Sintesis nanopartikel dan nanokomposit dilakukan dalam sistem dua fasa dengan menggunakan metode pengadukan kecepatan tinggi. Hasil sintesis selanjutnya dikarakterisasi menggunakan instrumentasi spektrofotometer UV-Vis, spektrofotometer UV-Vis DRS, spektroskopi FTIR, XRD, PSA, SEM-EDX, dan TEM. Hasil karakterisasi XRD nanokomposit ZnO/SmMnO3 menunjukkan nilai difraksi 2I¸ khas gabungan nanopartikel ZnO dan nanopartikel SmMnO3. Nanokomposit ZnO/SmMnO3 yang dikarakterisasi dengan TEM memiliki ukuran partikel sebesar 57,73 nm dengan distribusi ukuran rata- rata yang dikarakterisasi dengan PSA sebesar 86,57 nm dalam rentang 58,77-141,8 nm. Nanokomposit ZnO/SmMnO3 menunjukkan aktivitas fotodegradasi terhadap malasit hijau lebih baik daripada nanopartikel ZnO dan nanopartikel SmMnO3 dibawah sinar tampak selama 2 jam penyinaran. Presentase degradasi dengan nanokomposit ZnO/SmMnO3, nanopartikel ZnO, dan nanopartikel SmMnO3 sebesar 91,47%, 73,61%, dan 73,47%. Perhitungan kinetika reaksi fotodegradasi malasit hijau didapatkan bahwa nanokomposit ZnO/SmMnO3 mengikuti reaksi semu orde satu.

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ABSTRACT
In this study, the synthesis of ZnO nanoparticles, SmMnO3 nanoparticles, and ZnO / SmMnO₃ nanocomposites were successfully carried out using pulai leaves extract (Alstonia scholaris). Nanoparticles and nanocomposite synthesis were carried out in two-phase system which occupying the high speed stirring method. The synthesis results were then characterized using UV-Vis spectrophotometer, DRS UV-Vis, FTIR, XRD, PSA, SEM-EDX, and TEM. The results of XRD characterization of ZnO/SmMnO3 nanocomposite showed a typical diffraction of 2I¸ value of the combination ZnO nanoparticles and SmMnO3 nanoparticles. ZnO/SmMnO3 nanocomposite characterized by TEM has a particle size of 57,73 nm with an average size distribution characterized by PSA of 86,57 nm in the range 58,77-141,8 nm. ZnO/SmMnO3 nanocomposites showed better photodegradation activity on malachite green than ZnO nanoparticles and SmMnO3 nanoparticles under irradiation visible light for 2 hours . The percentage of degradation with ZnO/SmMnO3 nanocomposites, ZnO nanoparticles, and SmMnO3 nanoparticles was 91.47%, 73.61%, and 73.47% respectively. The calculation of the photodegradation reaction of malachite green kinetics found that ZnO/SmMnO3 nanocomposites comply a pseudo first-order reaction.

Abstrak :
Limbah pewarna merupakan salah satu limbah yang paling banyak dihasilkan dari industri tekstil. Salah satu zat berbahaya yang terdapat dalam limbah pewarna adalah Rhodamin B. Rhodamin B tergolong pewarna berbahaya karena yang memiliki sifat karsinogenik dan mutagenik pada manusia dan hewan. Untuk menghilangkan Rhodamin B pada limbah dari industri tekstil dapat dilakukan dengan fotodegradasi. Fotodegradasi dapat dilakukan dengan menggunakan material fotokatalis yang disebut sebagai degradasi dengan fotokatalisis. Oleh karena itu dikembangkan fotokatalis yang efektif digunakan dalam proses ini, salah satunya adalah metal organic frameworks (MOF) yang merupakan material semikonduktor berpori. Perpaduan logam dengan ligan yang bersifat fotoaktif serta modulasi dalam MOF dapat meningkatkan sifat fotokatalitik MOF. Pada penelitian ini disintesis MOF berbasis zirkonium dengan ligan perylene-3,4,9,10-tetrakarboksilat termodulasi asam amino glisina dengan metode solvotermal yang diuji sifat fotokatalitiknya dengan degradasi Rhodamin B. Dalam penelitian ini disintesis MOF dengan energi celah pita yang kecil pada kisaran 1,7-1,9 eV sehingga dapat digunakan sebagai fotokatalis. MOF dengan penambahan modulator sebanyak 10 ekuivalen memiliki respon fotokatalitik terbaik dengan persen degradasi 55% pada degradasi Rhodamin B 10 ppm dengan waktu degradasi selama 90 menit. ......Dye waste is one of the most waste generated from the textile industry. One of the hazardous substances contained in dye waste is Rhodamine B. Rhodamine B is classified as a dangerous dye because carcinogenic and mutagenic. To remove Rhodamine B in waste, it can be done by photodegradation. Photodegradation can be carried out using photocatalyst materials which is known as photocatalytic degradation. Therefore, an effective photocatalyst was developed to be used in this process, one of which is metal organic frameworks (MOF), which is a porous semiconductor material. The combination of metal with photoactive ligands and modulation in MOF can increase the photocatalytic properties of MOF. In this study, zirconium-based MOF was synthesized with perylene-3,4,9,10-tetracarboxylic ligand modulated by the amino acid glycine by the solvothermal method which was tested for photocatalytic properties by degradation of Rhodamine B. In this study, MOF was synthesized with a small band gap energy in the range of 1,7-1,9 eV so that it can be used as a photocatalyst. MOF with the addition of 10 equivalents of modulator has the best photocatalytic response with a degradation percentage of 55% at 10 ppm Rhodamine B degradation in 90 minutes.