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"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."

"Nanokomposit TiO2/CuO dengan variasi rasio Cu/Ti disusun menggunakan metode sol-gel. Sampel komposit dikarakterisasi dengan X-Ray Diffraction, Energy Dispersive X-Ray Spectroscopy, Field Emission Scaning, Brunauer-Emmett-Teller, UV-Visible Diffuse Reflectance Spectroscopy dan Electronic Spin Resonance Spectroscopy. Methylene blue digunakan sebagai model pewarna tekstil untuk mengevaluasi fotokatalitik, sonokatalitik dan fotosonokatalitik. Difraksi sinar-X dan dispersif energi analisis X-ray menegaskan bahwa hanya struktur monoklinik CuO dan struktur anatase TiO2 yang muncul di nanokomposit TiO2/CuO. Degradasi methylene blue menunjukkan bahwa penggabungan CuO di nanokomposit TiO2/CuO menunjukkan aktivitas fotokatalitik yang cukup tinggi, dan energi cahaya yang dapat dimanfaatkan lebih banyak dibandingkan TiO2 murni. Selain itu, degradasi methylene blue juga diselidiki menggunakan sistem sonokatalisis dan sistem fotosonokatalisis. Hasil penelitian menunjukkan bahwa semua data eksperimen mengikuti model pseudo-first order tapi laju konstanta fotosonokatalisis lebih tinggi dari proses fotokatalisis dan sonokatalisis individu masing-masing. Selain itu, kegiatan fotokatalitik, sonokatalitik dan fotosonokatalitik akan berkaitan dengan sifat struktural dan optik sampel. Mekanisme kegiatan katalitik akan dibahas.

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TiO2/CuO nanocomposite with different Cu/Ti ratios were prepared using sol-gel method. The obtained composite samples were characterized with X-Ray Diffraction, Energy Dispersive X-Ray Spectroscopy, Field Emission Scaning, Brunauer-Emmett-Teller, UV-Visible Diffuse Reflectance Spectroscopy and Electronic Spin Resonance Spectroscopy. Methylene blue was used as a model of textile dye to evaluate their photocatalytic, sonocatalytic and photosonocatalytic activities. X-ray diffraction and energy dispersive X-ray analysis confirmed that only monoclinic CuO and anatase TiO2 structures are present in TiO2/CuO nanocomposites. The degradation of methylene blue indicated that the incorporation of CuO in TiO2/CuO nanocomposite exhibited an appreciable higher photocatalytic activity, and more light energy could be utilized than pure TiO2. In addition, the degradation of methylene blue was also investigated using sonocatalysis and photosonocatalysis systems.

The results showed that all experimental data followed the pseudo-first order model but the rate constant of the sonophotocatalysis is higher than the respective individual photocatalysis and sonocatalysis process. Furthermore, the photocatalytic, sonocatalytic and photosonocatalytic activities will be related to their structural and optical properties. The mechanism of catalytic activities will be discussed."

"Nanokomposit TiO2/CuO dengan variasi rasio Cu/Ti disusun menggunakan metode sol-gel. Sampel komposit dikarakterisasi dengan X-Ray Diffraction, Energy Dispersive X-Ray Spectroscopy, Field Emission Scaning, Brunauer-Emmett-Teller, UV-Visible Diffuse Reflectance Spectroscopy dan Electronic Spin Resonance Spectroscopy. Methylene blue digunakan sebagai model pewarna tekstil untuk mengevaluasi fotokatalitik, sonokatalitik dan fotosonokatalitik. Difraksi sinar-X dan dispersif energi analisis X-ray menegaskan bahwa hanya struktur monoklinik CuO dan struktur anatase TiO2 yang muncul di nanokomposit TiO2/CuO. Degradasi methylene blue menunjukkan bahwa penggabungan CuO di nanokomposit TiO2/CuO menunjukkan aktivitas fotokatalitik yang cukup tinggi, dan energi cahaya yang dapat dimanfaatkan lebih banyak dibandingkan TiO2 murni. Selain itu, degradasi methylene blue juga diselidiki menggunakan sistem sonokatalisis dan sistem fotosonokatalisis. Hasil penelitian menunjukkan bahwa semua data eksperimen mengikuti model pseudo-first order tapi laju konstanta fotosonokatalisis lebih tinggi dari proses fotokatalisis dan sonokatalisis individu masing-masing. Selain itu, kegiatan fotokatalitik, sonokatalitik dan fotosonokatalitik akan berkaitan dengan sifat struktural dan optik sampel. Mekanisme kegiatan katalitik akan dibahas.

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TiO2/CuO nanocomposite with different Cu/Ti ratios were prepared using sol-gel method. The obtained composite samples were characterized with X-Ray Diffraction, Energy Dispersive X-Ray Spectroscopy, Field Emission Scaning, Brunauer-Emmett-Teller, UV-Visible Diffuse Reflectance Spectroscopy and Electronic Spin Resonance Spectroscopy. Methylene blue was used as a model of textile dye to evaluate their photocatalytic, sonocatalytic and photosonocatalytic activities. X-ray diffraction and energy dispersive X-ray analysis confirmed that only monoclinic CuO and anatase TiO2 structures are present in TiO2/CuO nanocomposites. The degradation of methylene blue indicated that the incorporation of CuO in TiO2/CuO nanocomposite exhibited an appreciable higher photocatalytic activity, and more light energy could be utilized than pure TiO2. In addition, the degradation of methylene blue was also investigated using sonocatalysis and photosonocatalysis systems. The results showed that all experimental data followed the pseudo-first order model but the rate constant of the sonophotocatalysis is higher than the respective individual photocatalysis and sonocatalysis process. Furthermore, the photocatalytic, sonocatalytic and photosonocatalytic activities will be related to their structural and optical properties. The mechanism of catalytic activities will be discussed."

"Green Synthesis Nanokomposit ZnO-CuO menggunakan ekstrak kulit biji Theobroma Cacao L dan uji aktivitas fotodegradasi zat warna metilen biru Abstract. Metode ramah lingkungan yaitu green synthesis of ZnO menggunakan ekstrak kulit biji coklat telah ditemukan. Percobaan tersebut menggunakan precursor Zn NO3 2 dan Cu NO3 2. TCL adalah bahan utama pengganti NaOH, yang terkandung dalam alkaloid yang memiliki kemampuan menghidrolisis melepaskan OH-. Persiapan dari ZnO bergantung pada rasio dari konsentrasi OH-/Cu2 . Identifikasi zat aktif pada ekstrak kulit biji coklat dapat dilakukan dengan menggunakan uji fitokimia. Green sintesis ZnO-CuO dikarakterisasi menggunakan UV-Vis DRS spectrophotometer, Fourier-transform infrared FT-IR spectroscopy, scanning electron microscopy-energy dispersive X-ray Spectroscopy SEM-EDS and X-ray diffraction analysis XRD.

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Name Taufik hidayatProgram Study Undergraduate Program Departement of ChemistryTitle Green Synthesis Nanocomposite ZnO CuO using Theobroma Cacao L Seed Extract and Fotodegradation Activity Test of Methylene Blue Abstract. Eco friendly method for green synthesis of ZnO using leaf extract of Theobroma cacao L was reported. It uses Zn NO3 2 and Cu NO3 2 precursor as raw material. TCL is as source of base to replace NaOH, due to contains alkaloid which has ability for hydrolyzing to release OH . Preparation of ZnO depends on the ratio of OH Cu2 concentrations. Identification of active compounds in leaf extract was obtained by phytochemical analysis. The green synthesis ZnO CuO was characterized by UV Vis DRS spectrophotometer, Fourier transform infrared FT IR spectroscopy, scanning electron microscopy energy dispersive X ray Spectroscopy SEM EDS and X ray diffraction analysis XRD."

"ABSTRAKPenelitian ini membahas pengaruh penambahan material nanographene platelets NGP dan nanoparticles Ag pada komposit Fe3O4/CuO/ZnO dengan menggunakan metode sol-gel dilanjutkan dengan metode co-precipitation. Komposit yang terbentuk kemudian dikarakterisasi dengan menggunakan X-ray diffraction XRD , Energy-Dispersive X-ray EDX , Thermal Gravimetric Analysis TGA , Fourier Transform Infrared FT-IR , UV-Visible Diffuse Reflectance UV-Vis , UV-Vis Absorbance spectroscopy, Scanning Electron Microscopy SEM dan Transmission Electron Microscopy TEM . Pengujian karakterisasi menunjukkan bahwa material yang disentasis merupakan gabungan dari nanoparticles Ag, Fe3O4, CuO, ZnO, dan NGP, sesuai dengan yang diinginkan. Pengujian aktivitas catalytic photo-, sono-, dan sonophotocatalytic dilakukan dengan menggunakan methylene blue MB sebagai model polutan pada keadaan cair. Penambahan Ag dan NGP menunjukkan peningkatan aktivitas catalytic dibandingkan dengan pure komposit Fe3O4/CuO/ZnO. Pengujian scavengers didapatkan bahwa hole dan hydroxyl radicals merupakan spesies dominan dalam aktivitas catalytic. Terakhir, sampel yang dibuat menunjukkan kestabilitasan dalam degradasi limbah selama 4 kali percobaan berulang reusability , hal tersebut menunjukkan potensi dari material Ag/Fe3O4/CuO/ZnO/NGP komposit sebagai degradasi limbah.

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ABSTRACTThis research discusses the effect of adding nanographene platelets NGP and Ag nanoparticles onto Fe3O4 CuO ZnO composites by using sol gel method followed by simple co precipitation method. The as prepared composites were characterized using X ray diffraction XRD , Energy Dispersive X ray EDX , Thermal Gravimetric Analysis TGA , Fourier Transform Infrared FT IR , UV Visible Diffuse Reflectance UV Vis , UV Vis Absorbance spectroscopy, Scanning Electron Microscopy SEM dan Transmission Electron Microscopy TEM . Characterization tests show that the as prepared samples are combination of desired Ag, Fe3O4, CuO, ZnO, and NGP nanoparticles. The catalytic activity photo , sono , and sonophotocatalytic was performed using methylene blue MB as the pollutant model in aqueous solution. The addition of Ag nanoparticles and NGP showed an increase in catalytic activity compared to pristine Fe3O4 CuO ZnO composites. The scavengers test showed that hole and hydroxyl radicals are the dominant species in catalytic activity. Finally, the Ag Fe3O4 CuO ZnO NGP composite exhibits good catalytic stability in four times cycling processes."

"Sampel nanopartikel coupled magnetite Fe3O4/ZnO dengan tiga variasi rasio molar disintesis dengan metode sol gel. Karakterisasi sampel dilakukan dengan menggunakan Field Emission Scanning Electron Microscope (FESEM), X-ray Diffraction (XRD), Electron Dispersive X-Ray (EDX), spektroskopi UV-Vis dan Vibrating Sample Magnetometer (VSM). Pengujian aktivitas fotokalitik dilakukan dengan mengamati degradasi larutan methylene blue (MB) sebagai model polutan organik di bawah penyinaran cahaya UV. Hasil analisis FESEM menunjukkan sampel nanopartikel coupled memiliki morfologi sferis. Hasil kurva XRD menunjukkan peningkatan intensitas seiring dengan meningkatnya rasio molar ZnO dalam nanopartikel coupled Fe3O4/ZnO. Keberadaan atom Fe, O dan Zn pada sampel nanopartikel coupled dikonfirmasi oleh spektrum EDX. Aktivitas fotokalitik yang paling baik ditunjukkan oleh sampel nanopartikel coupled rasio molar 1:5 dengan dosis sebanyak 20 mg/L pada kondisi pH 13. Nanopartikel Fe3O4 dan nanopartikel coupled Fe3O4/ZnO menunjukkan sifat feromagnetik yang memungkinkan sampel untuk dipisahkan secara magnetik dari dye methylene blue.

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Nanoparticle coupled magnetite Fe3O4/ZnO with various molar ratio has been syntesized using sol gel method. Characterization using Field Emission Scannig Electron Microscope (FESEM), X-Ray Diffraction (XRD), Electron Dispersive X-ray (EDX), UV-Vis Diffuse Reflectance and Vibrating Sampel Magnetometer (VSM) were conducted to identify morphology, structure, composition, optical and magnetic properties of nanoparticle coupled Fe3O4/ZnO. Photocatalytic activity studied by observing methylene blue (MB) degradation under UV light irradiation. FESEM shows Fe3O4/ZnO has spherical shape. XRD result shows ZnO phase intensity in nanoparticle coupled increase as ZnO molar ratio increase. The peaks corresponding to Fe, O and Zn atom were observed using EDX spectra. Maximum degradation of methylene blue was showed by 20 mg/L nanoparticle coupled with molar ratio 1:5 at pH 13. VSM result shows Fe3O4 and nanoparticle coupled samples exhibit ferromagnetic behavior. Therefore, samples can easily seperate from methylene blue using external magnetic."

"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. "

"Pada studi ini, saya menggunakan metode fotokatalitik untuk mendegradasi limbah cat pewarna organik dalam limbah air menggunakan MgFe2O4 dan MgFe2O4-nanographene (MgFe2O4/NGP) nanopartikel. MgFe2O4 dan MgFe2O4/NGP (mengandung persentase NGP yang bervariasi) disintesis melalui metode hidrotermal. Kedua bahan ini digunakan sebagai katalis dalam proses fotokatalitik mendegradasi limbah organic Methylene-Blue dalam solusi cair, dibawah radiasi cahaya merah. Karakteristik dari sample (MgFe2O4 & MgFe2O4/NGP) dilakukan menggunakan X-ray Diffraction, Raman Spectroscopy, UVVIS Spectroscopy, XRF, TGA, BJH, XPS, TEM, HRTEM, SAED, EDX dan BET. Hasil dari penelitian ini menunjukkan bahwa MgFe2O4/NGP mempunyai kemampuan fotokatalitik yang lebih baik dibandingkan dengan MgFe2O4. Efek dari konsentrasi NGP (wt%) untuk mendegradasi MB didiskusikan. Spesies aktif dalam proses fotokatalitik juga dipelajari melalui scavenger test.

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In the current study, we use the photodegradation method for the removal of organic dye molecule in wastewater using MgFe2O4 and MgFe2O4-nanographene platelets (MgFe2O4/NGP) nanoparticles. MgFe2O4 and MgFe2O4/NGP (containing various amounts of NGP) were synthesized using the hydrothermal method. Both of them used as a catalyst for photocatalytic degradation of methylene blue (MB), i.e. our organic dye in aqueous solution under red light irradiation. Characteristics of our samples (MgFe2O4 & MgFe2O4/NGP) were characterized using X-ray diffraction, Raman Spectroscopy, UVVIS Spectroscopy, XRF, TGA, BJH, XPS, TEM, HRTEM, SAED, EDX, and BET. The result of our work showed that MgFe2O4/NGP mostly have a better photocatalytic performance compared to pure MgFe2O4. The effect of NGP concentration (wt%) on the photocatalytic degradation of MB was discussed. Active species who'd take effect on the photocatalytic process was also studied by the scavenger test."

"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."

"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."