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"Nanokomposit Fe2O3/Au berpori telah berhasil disintesis dengan template kitosan menggunakan fraksi air Ekstrak Daun Gamal (Gliricidia sepium) sebagai reduktor dan capping agent dalam proses sintesis. Keberhasilan sintesis nanomaterial dikonfirmasi dari hasil karakterisasi yang dilakukan. Spektra FTIR menunjukkan adanya vibrasi khas logam Fe-O dengan oksigen pada rentang bilangan gelombang 467 dan 551cm-1. Karakterisasi SEM EDX menunjukkan bahwa AuNP terdeposisi di permukaan Fe2O3. Karakterisasi XRD menunjukkan bahwa terbentuknya kristalin nanopartikel α-Fe2O3. Dari pola XRD dan spektra FTIR menunjukkan bahwa penambahan AuNP tidak mengubah struktur dari Fe2O3. Uji aktivitas katalitik nanokomposit Fe2O3/Au berpori dilakukan sebagai katalis reduksi untuk senyawa 4-nitrofenol dengan NaBH4. Kondisi optimum nanokomposit untuk mereduksi senyawa 4-nitrofenol didapatkan pada massa katalis 5 mg dengan konsentrasi 4-nitrofenol sebesar 5 x 10-5M. Hasil studi kinetika menunjukkan bahwa reaksi reduksi mengikuti hukum laju orde pertama dengan nilai tetapan laju reaksi reduksi sebesar 0,0368 menit-1 untuk Fe2O3/Au berpori. Nilai ini lebih tinggi dibandingkan Fe2O3/Au NP sebagai perbandingan yang memiliki nilai tetapan laju reaksi 0.0172 menit-1

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Porous Fe2O3/Au nanocomposites have been successfully synthesized with chitosan templates using the water fraction of Gamal Leaf Extract (Gliricidia sepium) as a source of reductor and a capping agent in the synthesis process. The success of the nanomaterial synthesis was confirmed by the results of the characterization being carried out. FTIR spectra showed a distinctive vibration of Fe metal with oxygen in the wave number 467 and 551cm-1. SEM EDX characterization showed that AuNP deposited on the Fe2O3 surface. XRD characterization showed that crystalline α-Fe2O3 nanoparticles were formed. The XRD pattern and FTIR spectra show that the addition of AuNP does not change the structure of Fe2O3. The porous Fe2O3/Au nanocomposites was carried out as a reduction catalyst for 4-nitrophenol compounds with NaBH4. The optimum conditions for the nanocomposite to reduce 4-nitrophenol compounds were obtained at a catalyst mass of 5 mg with a 4-nitrophenol concentration of 5 x 10-5M. The results of the kinetics study show that the reduction reaction follows the first-order rate law with a reduction reaction rate constant of 0.0368 minutes-1 for porous Fe2O3/Au. This value is higher than Fe2O3/Au NP as a comparison which has a reaction rate constant of 0.0172 minutes-1, meaning porous Fe2O3/Au has better catalytic activity than Fe2O3/Au NP"

"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.

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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"Selulosa dapat diisolasi dari bambu yang akan digunakan untuk sintesis nanokomposit nanoselulosa yang dimodifikasi dengan nanopartikel anorganik TiO2 sehingga memiliki sifat unggul dari keduanya. Hasil sintesis yang diperoleh didukung dengan karakterisasi menggunakan instrumen FTIR, TEM, SEM, XRD, dan EDX. Rendemen selulosa hasil isolasi dari bambu diperoleh sebesar 60,8 . TiO2 hasil sintesis berukuran nano dan berstruktur anatase. Nanokomposit nano selulosa/TiO2 dapat diaplikasikan sebagai katalis untuk sintesis 5-hidroksimetilfurfural dari fruktosa yang menjadi alternatif penting dalam pembuatan biofuel dengan karakterisasi menggunakan HPLC. Kondisi optimum pembentukan 5-hidroksimetilfurfural dari fruktosa pada suhu 120oC selama 60 menit dengan komposisi fruktosa sebanyak 25 mg dan 50 mg katalis. Diperoleh persen yield sebesar 21,48 . Reaksi pembentukan 5-hidroksimetilfurfural dari fruktosa mengikuti kinetika orde satu dan diperoleh energi aktivasi sebesar 81,5 kJ/mol"

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""ABSTRACT"Cellulose can be isolated from bambu which will be used for synthesis of nanocomposite nano cellulose that is modified with inorganic nanoparticle TiO2, so it has excellent properties that comes from the combination between both characters. Characterization of synthesis result is conducted by using instrumentation such as FTIR, SEM, TEM, XRD, and EDX. The yield of isolated cellulose from bambu was obtained at 60.8 . The result of TiO2 synthesis was in nano sized and anatase structure. Nanocomposite based on nano Celllulose TiO2 can be applied as a catalyst to synthesis 5 hydroximetilfurfural from fructose which becomes an important alternative in making biofuel using High Pressure Liquid Chromatography HPLC characterization showed by percent yield. The optimum condition of synthesis 5 hydroxymethylfurfural from fructose at 120oC for 60 minutes with 25 mg fructose and 50 mg catalyst. A percent yield of 21.48 was obtained. The kinetic reaction of synthesis 5 hydroxymethylfurfural from fructose follow the first order kinetic and energy activation was obtained at 81.5 kJ mol."

"Pada penelitian ini, nanopartikel TiO2 telah dimodifikasi dengan InVO4 melalui metode green synthesis menggunakan ekstrak daun mangga (Mangifera indica L.). Ekstrak daun mangga fraksi air yang digunakan mengandung metabolit sekunder berupa alkaloid, saponin, tannin, dan polifenol yang berperan sebagai sumber basa lemah dan agen capping. Nanopartikel TiO2, InVO4, dan nanokomposit TiO2/InVO4 dikarakterisasi menggunakan FTIR, XRD, UV-Vis DRS, dan FESEM-EDS. Aktivitas fotokatalitik nanokomposit TiO2/InVO4 terhadap rifampicin di bawah iradiasi sinar tampak selama 120 menit diuji menggunakan spektrofotometer UV-Vis. Persentase fotodegradasi TiO2/InVO4 dengan massa optimum 8 mg menunjukkan persentase tertinggi yaitu 97,18% dibandingkan variasi kondisi lain yaitu katalis TiO2 (34,13%), InVO4 (74,93), adsorpsi (36,07%), dan fotolisis (12,43%). Serta kinetika reaksi fotokatalisis nanokomposit TiO2/InVO­4­ terhadap degradasi rifampicin mengikuti model pseudo orde satu dengan konstanta laju reaksi (k) sebesar 9,34 x 10-3 menit-1.

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In this research, TiO2 nanoparticles were modified with InVO4 by means of green synthesis method using mango (Mangifera indica L.) leaf extract. The water fraction of mango leaf extract consisted of secondary metabolites such as alkaloids, saponins, tannins, and polyphenols which act as sources of weak base and capping agent. TiO2, InVO4, and TiO2/InVO4 nanocomposites were characterized using FTIR, XRD, UV-Vis DRS, and FESEM-EDS. The photocatalytic activity of TiO2/InVO4 nanocomposites against rifampicin under visible light irradiation for 120 minutes was probed by UV-Vis spectrophotometer. The percentage of degradation of TiO2/InVO4 with an optimum mass of 8 mg showed the highest percentage of 97,18% compared to other conditions, catalyst TiO2 (34,13%), InVO4 (74,93), adsorption (36,07%), and photolysis (12,43%). Also, kinetic photocatalytic reaction of TiO2/InVO4 on rifampicin degradation follows pseudo-first order with a reaction rate constant (k) of 9,34 x 10-3 minutes-1."

"Pada penelitian ini, sintesis nanopartikel ZnO, Co2SnO4, dan nanokomposit ZnO/Co2SnO4 dilakukan secara green synthesis menggunakan ekstrak daun talas (Colocasia esculenta L. Schott) dalam sistem dua fasa (n-heksana – air). Kandungan metabolit sekunder yang terdapat pada ekstrak daun talas seperti alkaloid dan saponin akan berperan sebagai sumber basa lemah dan capping agent dalam proses sintesis. Selanjutnya, hasil sintesis akan dikarakterisasi dengan menggunakan Spektrofotometer UV-Vis, Spektrofotometer UV-Vis DRS, Spektroskopi FTIR, X-Ray Diffraction (XRD), dan Transmission Electron Microscopy (TEM). Berdasarkan hasil karakterisasi dengan spektrofotometer UV-Vis DRS didapatkan nilai band gap energy untuk nanopartikel ZnO, Co2SnO4, dan nanokomposit ZnO/Co2SnO4 masing-masing sebesar 3,08 eV, 1,6 eV, dan 2,44 eV. Nanokomposit ZnO/Co2SnO4 diuji aktivitas fotokatalitiknya terhadap malasit hijau. Berdasarkan hasil penelitian, uji aktivitas fotokatalitik nanokomposit ZnO/Co2SnO4 memiliki persen degradasi tertinggi pada kondisi optimum dengan berat sebesar 12 mg pada 5,0 x 10-6 M malasit hijau selama 120 menit di bawah sinar tampak, yaitu sebesar 92,63%.

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In this research, synthesis of ZnO, Co2SnO4 nanoparticles, and ZnO/Co2SnO4 nanocomposites were prepared by green synthesis using taro (Colocasia esculenta L.Schott) leaf extract in a two phase system (n-hexane – water). The content of secondary metabolites found in taro leaf extract such as alkaloid and saponin were roled as a source of weak base and capping agent in the synthesis process. Furthermore, the synthesis results were characterized by UV-Vis spectrophotometer, UV-Vis DRS spectrophotometer, FTIR spectroscopy, X-Ray Diffraction, and Transmission Electron Microscopy. UV-Vis DRS spectrophotometer characterization shows that band gap energy of ZnO, Co2SnO4 nanoparticles, and ZnO/Co2SnO4 nanocomposites were 3,08 eV, 1,6 eV, and 2,44 eV, respectively. ZnO/Co2SnO4 nanocomposites was applied for its photocatalytic activity to malachite green. Based on research results, the photocatalytic activity test of ZnO/Co2SnO4 nanocomposites had the highest degradation percentage of malachite green reached in the optimum condition of 12 mg mass catalyst and 5,0 x 10-6 M of malachite green concentration for 120 minutes under visible light, which was 92,63%."

"Nanokomposit MnFe2O4/NGP dengan variasi 5, 10, dan 15 wt.% digunakan untuksebagai katalis untuk mendegradasi methylene blue pada proses fotokatalitk dansonokatalitik. MnFe2O4 dan MnFe2O4/NGP 5, 10, 15 wt.% disintesis denganmenggunakan metode hydrothermal. Impuritas dan fase lain tidak ditemukan padapengukuran x-ray diffraction (XRD) dan x-ray fluorescence (XRF). KeberadaanNGP terkonfirmasi dari pengukuran XRD, thermogravimetric analysis (TGA),spektroskopi Raman, dan x-ray photoelectron spectroscopy (XPS). Penambahanluas sampel spesifik seiring bertambahnya NGP dikonfirmasi melalui pengukuranBrunauer-Emmet Teller (BET). Morfologi dari MnFe2O4 yang menyerupai persegidan cenderung berkumpul didapat dari pengukuran transmission electronmicroscopy (TEM). Katalis memiliki kemampuan degradasi yang lebih baik padaproses photocatalytic dengan cahaya tampak dibanding cahaya UV. Kondisi sistemterbaik dari katalis untuk mendegradasi methylene blue adalah pada dosis katalis0.2 g/L, konsentrasi H2O2 8 mL, dan pH 13. Penambahan NGP pada MnFe2O4terbukti meningkatkan kemampuan degradasi methylene blue. Katalis juga terbuktimemiliki stabilitas yang tinggi setelah digunakan sebanyak lima kali. Spesies aktifdari katalis pada proses fotokatalitik dan sonokatalitik adalah hidroksil radikal.

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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"

"Pada penelitian ini telah dilakukan sintesis nanokomposit nanochitosan/ZnO-CdO dengan nanochitosan sebagai support katalis dengan semikonduktor ZnO yang digabungkan dengan CdO yang dimanfaatkan untuk degradasi limbah zat warna methylene blue. Pada penelitian ini sintesis nanochitosan telah berhasil dilakukan dengan ukuran partikel sebesar 17,72 nm. Nanopartikel ZnO telah berhasil disintesis dengan ukuran partikel 30,65 nm dan energi band gap 3,17 eV. Nanopartikel CdO telah berhasil disintesis dengan ukuran partikel 23,14 nm dan energi band gap 2,13 eV. Komposit ZnO-CdO berhasil disintesis dengan energi band gap 2,42 eV, hal itu menunjukkan bahwa CdO dapat menurunkan energi band gap dari ZnO. Komposit ZnO-CdO yang disintesis memiliki luas permukaan 18,60 m2/g dengan analisis SEM berbentuk butiran tidak seragam. Nanokomposit nanochitosan/ZnO-CdO telah berhasil disintesis dengan ukuran kristal 20,82 nm, luas permukaan 40,34 m2/g, dan menggunakan TEM diperoleh ukuran rata-rata pertikel 23,97 nm. Nanokomposit nanochitosan/ZnO-CdO yang telah berhasil disintesis digunakan untuk fotokatalisis untuk mendegradasi zat warna methylene blue dan diperoleh persen degradasi 97,10%. Studi kinetika mengikuti kinetika orde satu dengan persamaan laju reaksi yang berarti laju reaksi bergantung pada konsentrasi methylene blue. Isoterm adsorpsi sesuai dengan isoterm Langmuir menunjukkan proses kemosorpsi yang mana proses degradasi zat warna methylene blue menggunakan nanokomposit nanochitosan/ZnO-CdO ini termasuk fotokatalisis. Berdasarkan hasil penelitian ini nanokomposit menggunakan support biopolimer seperti nanochitosan dengan ZnO-CdO memiliki potensi katalis yang baik untuk berbagai aplikasi yang ramah lingkungan.

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In this study, a nanochitosan based nanochitosan/ZnO-CdO nanocomposite was synthesized as a catalyst support with ZnO semiconductor combined with CdO which used for the degradation of methylene blue dye. In this study, nanochitosan was successfully synthesized with a particle of 17,72 nm. ZnO nanoparticle has been successfully synthesized with a particle size of 30,65 nm and band gap energy of 3,17 eV. CdO nanoparticle has been successfully synthesized with a particle size of 23,14 nm and band gap energy of 2,13 eV. ZnO-CdO composite was successfully synthesized with band gap energy of 2,42, it shows that CdO can reduce the band gap energy of ZnO. The ZnO-CdO composite obtaine a surface area of 18,60 m2/g by SEM analysis in the form of non-uniform grains. Nanochitosan/ZnO-CdO nanocomposite has been successfully synthesized with a crystal size of 20,82 nm, a surface area 40,34 m2/g, and using TEM an average particle size of 23,97 nm was obtained. The successfully synthesized nanochitosan/ZnO-CdO nanocomposite was used as a photocatalyst to degrade methylene blue dye, the optimum degradation percentage was 97,10%. In the study of kinetics following one order kinetic with the equation for the reaction rate is which means the reaction rate depends on the concentration of methylene blue dye. The study of adsorption isotherm according to Langmuir isotherm shows a chemosorption process in which the degradation process of methylene blue dye using nanochitosan/ZnO-CdO nanocomposite is photocatalytic. Based on the results of this study, nanocomposite using biopolymer support which nanochitosan have good catalyst potential for various environmentally friendly applications. "

"Health and environmental safety of nanomaterials addresses concerns about the impact of nanomaterials on the environment and human health, and examines the safety of specific nanomaterials. Understanding the unique chemical and physical properties of nanostructures has led to many developments in the applications of nanocomposite materials. While these materials have applications in a huge range of areas, their potential for toxicity must be thoroughly understood.Part one introduces the properties of nanomaterials, nanofillers, and nanocomposites, and questions whether they are more toxic than their bulk counterparts. Part two looks at the release and exposure of nanomaterials. The text covers sampling techniques and data analysis methods used to assess nanoparticle exposure, as well as protocols for testing the safety of polymer nanocomposites. It explains characterization techniques of airborne nanoparticles and life cycle assessment of engineered nanomaterials. Part three focuses on the safety of certain nanomaterials, including nanolayered silicates, carbon nanotubes, and metal oxides. In particular, it explores the potential ecotoxicological hazards associated with the different structures of carbon nanotubes and the safe recycling of inorganic and carbon nanoparticles. The final two chapters address the risks of nanomaterials in fire conditions, their thermal degradation, flammability, and toxicity in different fire scenarios."