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"Nanopartikel ZnO yang dimodifikasi oleh CTAB dan didop dengan empat variasi konsentrasi atom Ni berhasil dibuat melalui metode kopresipitasi. Seluruh sampel dikarakterisasi oleh pengukuran energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, electron spin resonance (ESR), field emission scanning electron microscope (FESEM), dan UV-Vis spectrophotometry. Hasil pengukuran memperlihatkan bahwa penambahan CTAB dan konsentrasi atom dopant mempengaruhi morfologi dan sifat optik dari seluruh sampel. Pengujian aktivitas fotokatalitik sampel dilakukan pada larutan methyl orange (MO) dan methylene blue (MB) di bawah paparan sinar UV selama 2 jam. Hasil yang diperoleh menunjukkan bahwa efisiensi kinerja degradasi fotokatalitik dari sampel meningkat seiring dengan bertambahnya konsentrasi atom dopant.

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CTAB-modified ZnO nanoparticles doped with four different concentrations of Ni were successfully synthesized by co-precipitation method. All samples were characterized using energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, electron spin resonance (ESR), field emission scanning electron microscope (FESEM), and UV-Vis spectrophotometry.

The results demonstrated that the addition of CTAB and doping concentration affect the morphology and optical properties of the samples. The photocatalytic activity test of all samples was studied by observing the degradation of methyl orange (MO) and methylene blue (MB) under UV light irradiation. The result indicates that the performance of photocatalytic activity from all samples increases along with the increasing concentration of atomic dopant."

"Nanopartikel ZnO didop Cu yang ditambah dengan Zeolit telah berhasil disintesis dengan metode Kopresipitasi dengan empat variasi doping Cu. Karakterisasi sampel nanopartikel ini diuji menggunakan Energy Dispersive X-ray (EDX), X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FE-SEM), Fourier Transform Infrared (FTIR), UV- Visible (UV-VIS) dan Electron Spin Resonance (ESR). Hasil karakterisasi EDX, FTIR dan ESR telah mengkonfirmasi berhasilnya doping atom Cu pada seluruh sampel. Hasil XRD menunjukkan bahwa seluruh sampel memiliki struktur heksagonal wurtzite beserta nilai grain size dan strain dari masing-masing sampel. Morfologi sampel ditunjukkan dari hasil FE-SEM yang menunjukkan permukaan sampel yang kasar. Hasil UV-Vis menunjukkan nilai celah pita energi yang berkurang dengan kehadiran doping logam Cu dan zeolit. Hasil uji fotokatalitik doping Cu sebanyak 7 at.% memiliki prosentase dekolorasi paling tinggi yaitu 77% sebanding dengan nilai rate tertinggi yaitu sebesar 0.0116 min-1.

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Cu-doped ZnO Nanoparticles assisted by Zeolite were successfully synthesized by Co-precipitation method with four doping variations of Cu. Characterization of nanoparticle samples were investigated by Energy Dispersive X-ray (EDX), X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FE-SEM), Fourier Transform Infrared (FTIR), UV- Visible (UV-VIS) dan Electron Spin Resonance (ESR). Characterizaton results of EDX, FTIR and ESR confirmed the doping of Cu in all samples. XRD results showed that all samples have hexagonal wutzite structure as well as grain size and strain calculations for each sample. Sample morphology was depicted by FE-SEM result showing the rough surface of sample. UV-Vis results showed the decreasing of the energy gap along with the loading of copper doping and zeolite. Photocatalytic activity result of Cu doping of 7 at% has the highest decolorization percentage of 77% which proportional to the highest rate constant of 0.0116 min-1."

"ZnO:Co/SDS dengan variasi konsentrasi dopant 3 - 13 at% disintesis menggunakan metode kopresipitasi Komposisi sampel dan keberadan dopant Co serta SDS diuji menggunakan spektroskopi Energy Dispersive X Ray EDX Fourier Transform Infrared FTIR dan Electron Spin Resonance ESR Pengaruh dopant dan SDS terhadap struktur kristal ZnO diuji melalui pengukuran X Ray Diffraction XRD Keempat sampel menunjukkan struktur hexagonal wurtzite Fase sekunder Zn OH 2 terdeteksi pada sampel ZnO Co SDS 13 at Pengujian Field Emission Scanning Electron Microscopy FESEM menunjukkan sampel yang disintesis memiliki bentuk menyerupai lembaran Pengaruh dopant dan SDS terhadap sifat optis sampel diuji melalui spektroskopi UV Vis Diffuse Reflectance UV Vis Analisis spektrum UV Vis dengan fungsi Kubelka Munk menunjukkan nilai energy gap sampel menurun dengan peningkatan konsentrasi dopant Aktivitas fotokatalitik sampel diuji dengan mengamati degradasi warna pada larutan uji metil jingga MO dan metilen biru MB Sampel mampu mendegradasi MO sebanyak 85 dan MB sebanyak 89 dengan pemaparan sinar Ultraviolet 200 nm selama 2 jam Spesies utama dalam proses fotodegradasi diuji dengan menambahkan scavenger pada larutan uji Pada sistem ini diketahui pengaruh elektron e hole h gugus radikal hidroksil OH.

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ZnO:Co/SDS with doping concentration varies between 3 ? 13 at% were synthesized by co-precipitation method. Sample composition also dopant and SDS existence characterized by Energy Dispersive X-Ray (EDX), Fourier Transform Infrared (FTIR), and Electron Spin Resonance (ESR) spectroscopy. The effect of dopant and SDS to crystal structure of ZnO were examined by X-Ray Diffraction (XRD). All samples shown hexagonal wurtzite structure. Secondary phase of Zn(OH)2 were detected at ZnO:Co/SDS 13 at%. Field Emission Scanning Electron Microscopy (FESEM) measurement shown the as synthesized samples has nanosheet-like shape. Dopant and SDS effect to optical properties observed by UVVis Diffuse Reflectance (UV-Vis DRS) spectroscopy. UV-Vis reflectance spekctrum were analyzed by Kubelka-Munk relation, it is shown the energy gap of samples decreased as the doping concentration increased. Photocatalytic activity of samples were tested by observing the degradation of methyl orange (MO) and methylene blue (MB) as dyes model. Under Ultraviolet irradiation (200 nm) irradiation for 2h, samples were able to degrade MO to 85% and MB to 89%. Main species in photodegradation mechanism tested by adding scavenger. It is shown the effect of electron (e-)> hole (h+)> hydroxyl radical species (OH-)."

"Nanopartikel ZnO:Fe/SDS dengan empat variasi konsentrasi Fe telah disintesis menggunakan metode kopresipitasi. Struktur dan sifat optis dari nanopartikel dikarakterisasi menggunakan Energy Dispersive X-Ray (EDX), X-Ray Difraction (XRD), Electron Spin Resonance (ESR), Field Emision - Scanning Electron Microscope (FESEM), Fourier Transform-Infrared (FTIR), dan spektroskopi UV-Vis. Aktivitas fotokatalitik nanopartikel diuji melalui degradasi Methyl Orange (MO) dan Methylene Blue (MB) di bawah sinar UV. Nanopartikel yang diperoleh memiliki fase tunggal dengan struktur heksagonal wurtzite. Untuk konsentrasi dopan 11 at. % terdapat fase tambahan berupa ZnFe2O4 yang menunjukkan batas solubilitas Fe dalam menggantikan Zn pada kisi ZnO. Aktivitas fotokatalitik mengalami peningkatan saat konsentrasi Fe meningkat berkaitan dengan terbentuknya trapping site di gap nanopartikel. Nanopartikel ZnO:Fe/SDS menunjukkan aktivitas fotokatalitik yang lebih tinggi dalam mendegradasi MB dibandingkan MO berkaitan dengan interaksi elektrostatik antara SDS dan dyes.

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ZnO:Fe/SDS nanoparticles with four varies of Fe concentration were prepared by coprecipitation methods. Structural and optical properties of nanoparticles were characterized using Energy Dispersive X-Ray (EDX), X-Ray Difraction (XRD), Electron Spin Resonance (ESR), Field Emision - Scanning Electron Microscope (FE-SEM), Fourier Transform-Infrared (FTIR), and UV-Vis Spectroscopy. The photocatalytic activity were evaluated by observing the photodegradation of Methyl Orange (MO) and Methylene Blue (MB) under UV light irradiation. The nanoparticles had single phases with hexagonal wurtzite structure. Sample ZnO:Fe/SDS 11 at. % showed the secondary phase of ZnFe2O4 which shown the solubility limit of Fe subtituted Zn in ZnO system. The photocatalytic of nanoparticles increased as the Fe doping concentration increased due to forming trapping site in band gap. ZnO:Fe/SDS nanoparticles showed higher photocatalytic activity in photodegradation of MB than MO due to electrostatic forced between SDS and dyes."

"Nanopartikel ZnO didop Cr disintesis menggunakan metode kopresipitasi untuk empat variasi konsentrasi Cr. Karakteristik nanopartikel dipelajari menggunakan Energy Dispersive X-Ray (EDX), X-Ray Difraction (XRD), Electron Spin Resonance (ESR), Field Emision - Scanning Electron Microscope (FESEM), Fourier Transform-Infrared (FTIR), and spektroskopi Ultra Violet- Visible (UV- Vis). Uji aktivitas nanopartikel diukur melalui degradasi Methyl Orange (MO) dan Methylene Blue (MB) pada daerah sinar Ultraviolet (UV). Hasil menunjukkan keberadaan Cr dan cetyltrimethylammonium bromide (CTAB) dalam sistem ZnO nanopartikel. Nanopartikel yang dihasilkan berfase tunggal dengan struktur heksagonal wurtzite dan mempunyai bentuk spherical-like. Peningkatan konsentrasi dopan Cr dan kehadiran surfaktan kationik CTAB menyebabkan berkurangnya celah energi dan lebih lanjut lagi meningkatkan aktivitas fotokatalitik. Kehadiran surfaktan kationik CTAB menyebabkan nanopartikel ZnO didop Cr lebih efektif dalam mendegradasi zat pewarna anionik MO dibanding kationik MB.

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Cr doped ZnO nanoparticles were synthesized by coprecipitation methods with four variation Cr concentrations. The nanoparticles were characterized by using Energy Dispersive X-Ray (EDX), X-Ray Difraction (XRD), Electron Spin Resonance (ESR), Field Emision - Scanning Electron Microscope (FESEM), Fourier Transform-Infrared (FTIR), and UltraViolet-Visible (UV-Vis) Spectroscopy. The photocatalytic activity of nanoparticles were evaluated by measuring degradation of Methyl Orange (MO) and Methylene Blue (MB) in Ultraviolet (UV) region. The results confirmed the presence of Cr dopant and cationic surfactant cetyltrimethylammonium bromide (CTAB) in the ZnO nanoparticles system. The resulting nanoparticles have single-phases with hexagonal wurzite structures and spherical-like shapes. Increasing the Cr dopant concentrations and the presence of cationic surfactant CTAB cause a reduction in energy gap and more futher improve the photocatalytic activity. The presence of cationic surfactant CTAB causes the Cr doped ZnO nanoparticles were more effective in degrading MO anionic dyes than MB cationic dyes."

"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."

"Campuran Oksida Seng/Titanium Dioksida/Oksida Tembaga (ZnO/TiO2/CuO) dengan lima variasi rasio molar CuO disintesis dengan menggunakan metode sol-gel dan dikarakterisasi menggunakan Energy Dispersive X-Ray (EDX), X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) dan UV-visible Diffuse Reflectance Spectroscopy (UV- DRS). Aktivitas fotokatalitik diamati menggunakan larutan metilen biru (MB) di bawah pemaparan sinar Ultraviolet (UV) dan cahaya tampak dengan metal oksida ZnO/TiO2 sebagai pembanding. Hasil aktivitas fotokatalitik menunjukkan sampel dengan rasio molar CuO sebesar 0.5 dapat mendegradasi lebih baik di bawah paparan sinar UV dan cahaya tampak. Kondisi optimum aktivitas fotokatalitik didapatkan pada kondisi pH 13, dosis fotokatalis 0.2 g/L dan konsentrasi awal MB 20 mg/L baik di bawah paparan sinar UV maupun cahaya tampak.

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Zinc Oxide/Titanium Dioxide/Copper Oxide (ZnO/TiO2/CuO) metal oxide mixture with five various CuO molar ratio were synthesized using sol-gel method and were characterized by Energy Dispersive X-Ray (EDX), X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Ultraviolet- visible Diffuse Reflectance Spectroscopy (UV-DRS). Photocatalytic activities were observed by using methylene blue (MB) solution under Ultraviolet (UV) light and visible light irradiation using photocatalytic activity of ZnO/TiO2 metal oxide mixture as comparison. The result shows sample with 0.5 ratio molar of CuO have higher degradation capability on both UV light and visible light irradiation. Photocatalytic activity optimum condition were obtained at pH 13, 0.2 g/L of photocatalyst and 20 mg/L of MB initial concentration."

"Nanopartikel oksida seng (ZnO) yang diberi dopan kromium (Cr) dan penambahan 10 % montmorillonite (MMT) disintesis dengan metode kopresipitasi untuk empat variasi persen atom Cr. Nanopartikel dikarakterisasi menggunakan X-Ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Fourier Transform Infrared (FTIR), UV-Visible Diffuse Reflectance (UV-Vis) dan Electronic Spin Resonance (ESR). Pengujian aktivitas fotokatalitik dilakukan menggunakan model polutan methylene blue dengan paparan sinar UV. Penambahan montmorillonite dan dopan Cr pada ZnO dapat meningkatkan degradasi methylene blue dengan Cr doped ZnO/MMT 10 at.% menunjukkan degradasi maksimum dengan kondisi optimum dosis fotokatalis 0.7 g/L dan konsenstrasi larutan 20 mg/L. Spesies dominan pada aktivitas fotokatalitik adalah hole dan OH● berturut-turut.

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Chromium (Cr) doped zinc oxide (ZnO) nanoparticles with 10% montmorillonite (MMT) addition were synthesized by co-precipitation method for four chrome atomic percentage variations. Samples were characterized by X-Ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Fourier Transform Infrared (FTIR), UV-Visible Diffuse Reflectance (UV-Vis) and Electronic Spin Resonance (ESR). Photocatalytic were evaluated using methylene blue under UV light irradiation. MMT addition and Cr dopant to ZnO nanoparticles enhance methylene blue degradation with the optimum conditions are 0.7 g/L of nanoparticle and 20 mg/L of methylene blue initial concentration. Hole and OH● were identified as dominant species of photocatalytic activity."

"Nanokomposit ZnO/CuO dengan lima variasi molar ZnO:CuO (1:3, 1:1, 1:0.5, 1:0.3, dan 1:0.1) telah disintesis dengan menggunakan metode sol-gel. Pengukuran X-ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Field Emission Scanning Electron Microscopy (FESEM), nitrogen adsorption spectroscopy, Electron Spin Resonance (ESR), dan UV-Visible spectroscopy dilakukan untuk mengindentifikasi struktur, morfologi, luas permukaan, resonansi ion-ion, dan nilai celah energi dari nanokomposit. Aktivitas katalitik dari nanokomposit ZnO/CuO diuji dibawah pemaparan cahaya visible, ultraviolet, ultrasonik, dan gabungan antara visible/UV dengan ultrasonik dalam mendegradasi larutan pewarna methylene blue (MB). Hasil aktivitas katalitik dari nanokomposit ZnO/CuO menunjukkan aktivitas photosonocatalytic mempunyai performa lebih baik dibandingkan aktivitas photocatalytic dan sonocatalytic. Penambahan beberapa scavenger menunjukkan hole merupakan spesies aktif yang berperan paling penting dalam mekanisme katalitik.

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ZnO/CuO nanocomposites with five different ZnO:CuO ratios (1:3, 1:1, 1:0.5, 1:0.3 and 1:0.1) were prepared using sol-gel method. X-ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Field Emission Scanning Electron Microscopy (FESEM), nitrogen adsorption spectroscopy, Electron Spin Resonance (ESR) and UV-Visible spectroscopy were employed to investigate the structural, morphology, surface area, ions resonance and energy band gap of nanocomposites. The catalytic activity of ZnO/CuO nanocomposites were tested under visible light, ultraviolet light, ultrasound irradiation and the combination of visible/UV light with ultrasound irradiation on the degradation of methylene blue (MB) aqueous solution. The observed catalytic activity of nanocomposites shows that photosonocatalytic has better performance than photocatalytic and sonocatalytic activity. The addition of scavengers suggested that holes are the most important active species in the catalytic mechanism."

"Nanopartikel Besi Oksida dan nanokomposit Besi Oksida/NGP (NanoGraphene platelets) sebagai material aditif telah disintesis menggunakan metode sol-gel. Komposit PCM (Phase change material) SA (Stearic acid)-Besi Oksida dan SA-Besi Oksida/NGP disintesis menggunakan metode sonifikasi dengan varisis wt.% yaitu 1 wt.%, 3 wt.% dan 5 wt.%. Sampel dikarakterisasi dengan X-Ray diffraction, Fourier Transform Infrared Spectroscopy, Energy Dispersive X-Ray, Field Emission Scanning Electron Microscope, Differential Thermal Analysis-Thermogravimetric Analysis dan Differential Scanning Calorimetry. Nanokomposit memperlihatkan fase gabungan struktur kristal cubic spinel dengan bidang struktur NGP. Spektrum FTIR mengkomfirmasi pencampuran material aditif pada Stearic acid tidak merubah struktur ikatan kimia. Nanokomposit tercampur dispersi dengan baik di atas Stearic acid dan sisa jumlah presentase kehilangan berat dalam kurva Thermogravimetric sama dengan variasi wt.%. Hasil karakterisasi sifat termal komposit PCM memperlihatkan peningkatan kapasitas panas dan kalor latent. Peningkatan kalor latent maksimum pada SA-Besi Oksida/NGP sebesar 23% dan SA-Besi Oksida/NGP sama dengan 30% terjadi pada wt.% penambahan yang sama.

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Nanopartikel Iron oxide and nanocomposite Iron oxide/NanoGraphene platelets (NGP) as material additives have been synthesized using sol-gel method. Phase change material (PCM) composites SA(Stearic acid)-Iron oxide and SA-Iron oxide/NGP have been synthesized using sonication method with various wt.% respectively by 1 wt.%, 3 wt.% and 5 wt.%. Sample were characterized with various method such as X-Ray diffraction, Fourier Transform Infrared Spectroscopy, Energy Dispersive X-Ray, Field Emission Scanning Electron Microscope, Differential Thermal Analysis-Thermogravimetric Analysis and Differential Scanning Calorimetry. Nanocomposite show the mixture of cubic spinel crystal structures with plane of NGP structure. The FTIR spectra confirmed that mixing of material additivies with Stearic acid not showing changes in chemical structure. Nanocomposite well dispersed in surface of Stearic acid and weight loss of PCM composites in Thermogravimetric curve same as with wt.% addition.Thermal characterization of PCM composites shows that enhancement in heat capacity and latent heat. The enhancement of latent heat in SA-Iron oxide and SA-Iron oxide/NGP by about 23 % and 30% using the same 1 wt. % of material additives."