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"Nanohybrid iron oxide titanium dioxide copper oxide dengan tiga variasi molar 1 1 1 1 3 1 dan 1 5 1 telah disintesis menggunakan metode sol gel Pengukuran X Ray Diffraction XRD Field Emission Scanning Electron Microscopy FESEM Energy Dispersive X rays EDX UV Vis Spectroscopy dan Vibrating Sample Magnetometer VSM digunakan untuk menentukan sifat struktur morfologi nilai energy gap optik dan sifat magnetik dari sampel nanohybrid Pengujian aktivitas fotokatalitik sampel nanohybrid dilakukan dengan mengamati degradasi warna methylene blue MB dibawah pemaparan cahaya ultraviolet dan tampak Hasil menunjukkan keberadaan copper oxide seiring dengan peningkatan rasio molar titanium dioxide mempengaruhi aktivitas fotokatalitik nanohybrid Nanohybrid dengan rasio molar 1 5 1 menunjukkan aktivitas fotokatalitik yang paling baik untuk pemaparan dengan cahaya ultraviolet sedangkan untuk pemaparan dengan cahaya tampak didapatkan dengan rasio molar 1 1 1 Selain itu fotokatalis nanohybird dapat dipisahkan setelah proses reaksi menggunakan magnet eksternal Penambahan scavenger menunjukkan hole memiliki peranan penting dalam proses degradasi methylene blue

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Iron oxide titanium dioxide copper oxide nanohybrids with three different molar ratios 1 1 1 1 3 1 and 1 5 1 were successfully prepared by sol gel method X Ray Diffraction XRD Field Emission Scanning Electron Microscopy FESEM Energy Dispersive X rays EDX UV ndash Vis spectroscopy and Vibrating Sample Magnetometer VSM techniques were employed to determine the structure morphology optical gap energy and magnetic properties of the as prepared samples Photocatalytic examination of the nanohybrids was carried out using aqueous solution of methylene blue MB under ultraviolet and visible light irradiation The results demonstrate that the increase molar ratio of titanium dioxide and the addition of copper oxide to iron oxide titanium dioxide cooper oxide has remarkable influence on the photocatalytic activity The nanohybrids with 1 5 1 molar ratio has superior activity in degradation of MB under ultraviolet light while under visible light the maximum degradation is reached by sample with molar ratio 1 1 1 Furthermore the photocatalysts can be separated from the reaction system simply by applying an external magnetic Active species on photocatalytic activity were investigated by measuring the photocatalytic degradation in the presence of scavenger The results suggested that holes play the most important role in degradation of methylene blue."

"Dalam penelitian ini nanopartikel Bi2O3, nanopartikel Fe2O3, dan nanobimetal oksida BiFeO3 telah berhasil disintesis menggunakan metode green synthesis dengan ekstrak daun okra. Kandungan metabolit sekunder yang terdapat dalam ekstrak daun okra seperti alkaloid digunakan sebagai agen penghidrolisa (sumber basa lemah -OH), sedangkan saponin dan flavonoid digunakan sebagai agen penstabil (capping agent). Hasil sintesis nanobimetal oksida BiFeO3 selanjutnya dikarakterisasi menggunakan UV-Vis RS, FTIR, XRD, SEM, dan TEM. Hasil karakterisasi TEM dari nanobimetal oksida BiFeO3 menunjukkan morfologi spherical dan cenderung beraglomerasi. Hasil karakterisasi TEM dari nanobimetal oksida BiFeO3 memiliki struktur kristal rhombhohedral dengan rata-rata ukuran kristal sebesar 14, 55 nm. Selanjutnya hasil karakterisasi UV-Vis DRS dari nanopartikel Bi2O3, nanopartikel Fe2O3, dan nanobimetal oksida BiFeO3 memiliki nilai energi bandgap berturut-turut 2,87 eV, 2,11 eV, dan 2,00 eV. Aktivitas fotokatalitik nanobimetal oksida BiFeO3 dalam mendegradasi methylene blue lebih baik dibandingkan dengan nanopartikel Bi2O3 dan nanopartikel Fe2O3 dengan persen degradasi berturut0turut sebesar 94,04 %, 67,11 %, dan 80,44 %. Kinetika fotodegradasi terhadap methylene blue menggunakan fotokatalis BiFeO3 mengikuti kinetika reaksi orde pseudo 1.

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In this research, Bi2O3 nanoparticles, Fe2O3 nanoparticles, and BiFeO3 nanobimetallic oxide have been successfully synthesized using green synthesis method with okra leaf extract. The content of secondary metabolites contained in okra leaf extracts such as alkaloids is used as a hydrolyzing agent (weak base source -OH), while saponins and flavonoids are used as stabilizing agents (capping agents). The results of the synthesis of BiFeO3 nanobimetallic oxide were then characterized using UV-Vis RS, FTIR, XRD, SEM, and TEM. The results of TEM characterization of BiFeO3 nanobimetallic oxide show spherical morphology and tend to agglomerate. The results of TEM characterization of BiFeO3 nanobimetallic oxide have a rhombhohedral crystal structure with an average crystal size of 14.55 nm. Furthermore, the results of UV-Vis DRS characterization from Bi2O3 nanoparticles, Fe2O3 nanoparticles, and BiFeO3 nanobimetallic oxide have bandgap energy values respectively 2.87 eV, 2.11 eV and 2.00 eV. The photocatalytic activity of BiFeO3 nanobimetallic oxide in degrading methylene blue is better than that of Bi2O3 nanoparticles and Fe2O3 nanoparticles with percent degradation of 94.04%, 67.11%, and 80.44%, respectively. The kinetics of photodegradation against methylene blue using BiFeO3 photocatalysts follow the kinetics of first-order pseudo reaction."

"Ekstrak daun kecubung EDK dapat dimanfaatkan sebagai sumber basa lemah, pengoksidasi dan penstabil dalam green synthesis nanopartikel cerium IV oksida. Cerium III nitrat direaksikan dengan ekstrak daun kecubung pada suhu 80oC dan pengadukan selama 4 jam dan dikalsinasi pada suhu 400oC selama 2 jam. Pembentukan koloid nanopartikel cerium IV oksida dilakukan dengan mengamati pergeseran panjang gelombang 297 nm ke 252 nm. Karakterisasi nanopartikel cerium IV oksida dilakukan menggunakan TEM, SEM, XRD, spektrofluorometer dan PSA. Nanopartikel cerium IV oksida memiliki ukuran 5-10 nm dengan bentuk sphere. Pengukuran XRD menunjukkan bentuk kristal nanopartikel cerium IV oksida adalah kubik. Sifat antioksidan nanopartikel cerium IV oksida dimanfaatkan dalam body lotion dan diamati aktivitasnya terhadap senyawa radikal DPPH. DPPH diubah menjadi senyawa non-radikal dan diamati penurunan absorbansi warna ungu DPPH pada spektrofotometer UV-Vis.

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Cerium IV oxide nanoparticles. Cerium III nitrate was reacted with kecubung leaf extract at 80oC and stirring for 4 hours then calcinated at 400oC for 2 hours. Colloid of cerium IV oxide was observed with UV Vis spectrophotometer and wavelength shifted from 297 nm to 252 nm. Characterization of cerium IV nanoparticles using TEM, SEM, XRD, spectrofluorometer and PSA. Size of cerium IV oxide nanoparticles in range 5 10 nm with sphere form. Characterization with XRD showed shape of cerium IV oxide nanoparticles is cubic. Antioxidant properties of cerium IV oxide can be used in body lotion using DPPH as radical compound. DPPH reacted with cerium IV oxide and changed to non radical compound. This reaction can be observed with UV Vis spectrophotometer."

"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."

"Green synthesis nanopartikel Nd2O3, Ag2O dan nanopartikel Nd2O3-Ag2O dilakukan karena mudah, murah dan ramah lingkungan. Dalam penelitian ini, ekstrak daun afrika (Vernonia Amygdalina Del.) kemudian diberi nama EDA digunakan untuk mensintesis nanopartikel Nd2O3-Ag2O. Metabolit sekunder pada EDA berperan sebagai sumber basa dan capping agent, yang ditentukan melalui uji fitokimia. Pola difraksi dan kristalinitas ketiga nanopartikel tersebut dikonfirmasi menggunakan X-Ray Diffraction, sedangkan morfologi ditentukan menggunakan Scanning Electron Microscopy-Energy Dispersive X-ray Analysis dan Transmitted Electron Microscopy. Fourier Transform-Infra Red digunakan untuk menunjukkan interaksi antara EDA dengan nanopartikel. Bilangan gelombang Nd-O pada nanopartikel Nd2O3 muncul di daerah 426 cm-1, Ag-O pada nanopartikel Ag2O di daerah 825 cm-1. Sedangkan bilangan gelombang Ag-O (855 cm-1), Nd-O (424 dan 667 cm-1) terdapat pada nanopartikel Nd2O3-Ag2O. Ukuran distribusi dari ketiganya berada di antara 1-100 nm yang dikonfirmasi menggunakan Particle Size Analyzer. Band gap nanopartikel Nd2O3-Ag2O yaitu sebesar 3,29 eV. Aktivitas fotokatalitik nanopartikel Nd2O3-Ag2O disimulasikan terhadap degradasi Metilen Biru (MB). Hasil degradasi sebesar 93, 71%.

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Green synthesis of Nd2O3, Ag2O and Nd2O3-Ag2O nanoparticles has been investigated lately due to its properties of inexpensive, easy to use, and eco-friendly material. At current research, Vernonia amygdalina Del. leaf extract was used to synthesize Nd2O3, Ag2O and Nd2O3-Ag2O nanoparticles. The secondary metabolite of Vernonia amygdalina Del. leaf extract plays a role as a base source and a capping agents, which can be determined by phytochemical test. The diffraction pattern and crystallinity of Nd2O3, Ag2O and Nd2O3-Ag2O nanoparticles were confirmed by using X-ray Diffraction, while the morphology can be determined using Scanning Electron Microscopy-Energy Dispersive X-ray Analysis and Transmitted Electron Microscopy. Fourier Transform-Infra Red (FT-IR) spectra was used to show the interaction between Vernonia amygdalina Del. leaf extract and nanoparticles. FT-IR characterization showed the wave number of Nd2O3 at 426 cm-1, Ag2O at 825 cm-1, and Nd2O3-Ag2O nanoparticles at 424 and 855 cm-1. The size distribution of Nd2O3, Ag2O and Nd2O3-Ag2O nanoparticles at 1-100 nm were confirmed by Particle Size Analyzer. UV-Vis DRS characterization proved the energy band gap of Nd2O3-Ag2O nanoparticles at 3,29 eV. The photocatalytic activity of Nd2O3-Ag2O nanoparticles was observed by determining the degradation of methylene blue, which was identified at 93.71%."

"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%."