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"Resistansi listrik lapisan tipis tin doped indium oxide (In203:Sn, ITO) yang dibuat dengan cara dc magnetron sputtering telah diteliti. Resistivitas yang diukur dengan cara empat titik berkisar dari 1.2 x 10'3 Slcm sampai 7.9 x 10-3 SZcm tergantung dari kadar oksigen pada temperatur ruangan. Di bawah temperatur 100 K, kerapatan pembawa muatan mendominasi konduktivitas sehingga dapat dikatakan bahwa ITO bersifat sebagai semikonduktor dengan energi aktivasi dari 2 x 10-6 eV sampai 1 x 104 eV. Dan pengaruh mobilitas menjadi konstan sehingga koefisien temperatur a dapat dianggap nol. Karenanya itu di bawah temperatur 100 K konduktivitas dapat ditulis sebagai d = o-o exp(-AE 1 kT) . Di atas temperatur 150 K mobilitas pembawa muatan mendominasi konduktivitas, sehingga ITO menyerupai logam dengan temperatur koefisien a dari 1.7 x 10K-1 sampai 4.2 x 104 K"1. Di atas 150 K, bentuk konduktivitas sebagai fungsi temperatur, dapat ditulis sebagai o = o exp(-dE/ kT) 1(1 + aT).Pengaruh kadar oksigen yang dimasukkan pada waktu sputtering sangat besar terhadap resistivitas maupun energi aktivasi. Resistivitas bertambah besar sebanding kenaikan kadar oksigen yang dimasukkan pada waktu sputtering. Namun, energi aktivasi bertambah besar sebanding kenaikan kadar oksigen hanya di bawah 100 K. Di atas 150 K, energi aktivasi mulai menjadi konstan yakni dengan harga sekitar 2 x 104 eV. Resistivitas paling kecil dan cenderung lebih bersifat logam ketika tidak dimasukkan gas oksigen ( 0 % ), sedangkan resistivitas paling besar dan lebih bersifat semikonduktor ketika dimasukkan gas oksigen 8.1 %."

"PT. X mengembangkan sistem powderisasi timah (timah putih, Sn) melalui metode atomisasi gas. Sisa output yang off-spec masih memiliki kandungan timah sekitar 98%. Terdapat peluang yang cukup besar dalam pengolahan limbah powderisasi timah ini menjadi senyawa turunan timah bernilai tambah tinggi, salah satunya katalis. Pada penelitian ini dilakukan pengolahan limbah powderisasi timah menjadi prekursor katalis sulfated tin oxide. Limbah powderisasi timah berupa powder timah yang off-spec dilakukan pretreatment leaching untuk mendapatkan senyawa SnCl2. SnCl2 yang dihasilkan diproses lebih lanjut menjadi SnSO4. Katalis sulfated tin oxide disintesis dari SnSO4 menggunakan metode kalsinasi. Uji aplikasi katalis dilakukan pada reaksi esterifikasi asam asetat. Senyawa turunan timah yang dihasilkan dianalisis menggunakan X-Ray Diffraction, Scanning Electron Microscopy-Energy Dispersive X-Ray, dan Optical Microscopy untuk mendapatkan struktur morfologi kristal dan komposisi senyawanya. Analisis gugus fungsi dilakukan pada uji Fourier Transform InfraRed Spectroscopy sementara sifat termal dianalisis menggunakan Differential Thermal Analysis. Hasilnya diperoleh SnCl2 dengan yield 95%, SnSO4 berbentuk kristal dengan penambahan plasticizer PEG 6000 dengan ukuran 187-329 μm, serta katalis sulfated tin oxide dengan ukuran 27-72 nm. Aplikasi katalis pada reaksi esterifikasi asam asetat dengan etanol menghasilkan konversi sebesar 35,7 % dan 41,5%.

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X company developed a tin powderization system through the gas atomization method. The remaining off-spec output still has a tin content of around 98%. There is considerable opportunity in processing this tin powder waste into a high value-added tin derivative, one of which is a catalyst. Therefore, this research carried out the processing of tin powder waste into precursor sulfated tin oxide catalysts. The tin powder waste in the form of off-spec tin powder was carried out pretreatment leaching to obtain SnCl2 compounds. The SnCl2 produced is further processed into SnSO4. The sulfated tin oxide catalyst was synthesized from SnSO4 using a calcination method. The catalyst application test is carried out on the reaction of esterification of acetic acid. The resulting tin derivative was analyzed using X-Ray Diffraction, Scanning Electron Microscopy-Energy Dispersive X-Ray, and Optical Microscopy to obtain the crystal morphological structure and composition of its compounds. Functional group analysis was performed in the Fourier Transform InfraRed Spectroscopy test while thermal properties were analyzed using Differential Thermal Analysis. The results obtained are SnCl2 with a yield of 95%, SnSO4 is crystalline with the addition of PEG 6000 plasticizer with a size of 187-329 μm, and sulfated tin oxide catalyst with a size of 27-72 nm. The application of the catalyst in the esterification reaction of acetic acid with ethanol resulted in conversions of 35.7% and 41.5%, respectively."

"PT. X mengembangkan sistem powderisasi timah (timah putih, Sn) melalui metode atomisasi gas. Sisa output yang off-spec masih memiliki kandungan timah sekitar 98%. Terdapat peluang yang cukup besar dalam pengolahan limbah powderisasi timah ini menjadi senyawa turunan timah bernilai tambah tinggi, salah satunya katalis. Pada penelitian ini dilakukan pengolahan limbah powderisasi timah menjadi prekursor katalis sulfated tin oxide. Limbah powderisasi timah berupa powder timah yang off-spec dilakukan pretreatment leaching untuk mendapatkan senyawa SnCl2. SnCl2 yang dihasilkan diproses lebih lanjut menjadi SnSO4. Katalis sulfated tin oxide disintesis dari SnSO4 menggunakan metode kalsinasi. Uji aplikasi katalis dilakukan pada reaksi esterifikasi asam asetat. Senyawa turunan timah yang dihasilkan dianalisis menggunakan X-Ray Diffraction, Scanning Electron Microscopy-Energy Dispersive X-Ray, dan Optical Microscopy untuk mendapatkan struktur morfologi kristal dan komposisi senyawanya. Analisis gugus fungsi dilakukan pada uji Fourier Transform InfraRed Spectroscopy sementara sifat termal dianalisis menggunakan Differential Thermal Analysis. Hasilnya diperoleh SnCl2 dengan yield 95%, SnSO4 berbentuk kristal dengan penambahan plasticizer PEG 6000 dengan ukuran 187-329 μm, serta katalis sulfated tin oxide dengan ukuran 27-72 nm. Aplikasi katalis pada reaksi esterifikasi asam asetat dengan etanol menghasilkan konversi sebesar 35,7 % dan 41,5%.

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X company developed a tin powderization system through the gas atomization method. The remaining off-spec output still has a tin content of around 98%. There is considerable opportunity in processing this tin powder waste into a high value-added tin derivative, one of which is a catalyst. Therefore, this research carried out the processing of tin powder waste into precursor sulfated tin oxide catalysts. The tin powder waste in the form of off-spec tin powder was carried out pretreatment leaching to obtain SnCl2 compounds. The SnCl2 produced is further processed into SnSO4. The sulfated tin oxide catalyst was synthesized from SnSO4 using a calcination method. The catalyst application test is carried out on the reaction of esterification of acetic acid. The resulting tin derivative was analyzed using X-Ray Diffraction, Scanning Electron Microscopy-Energy Dispersive X-Ray, and Optical Microscopy to obtain the crystal morphological structure and composition of its compounds. Functional group analysis was performed in the Fourier Transform InfraRed Spectroscopy test while thermal properties were analyzed using Differential Thermal Analysis. The results obtained are SnCl2 with a yield of 95%, SnSO4 is crystalline with the addition of PEG 6000 plasticizer with a size of 187-329 μm, and sulfated tin oxide catalyst with a size of 27-72 nm. The application of the catalyst in the esterification reaction of acetic acid with ethanol resulted in conversions of 35.7% and 41.5%, respectively."

"Dalam waktu yang lama, awalnya dilaporkan bahwa emas secara katalitik dianggap tidak aktif. Namun pada tahun 1980-an nanokatalis heterogen berbasis emas telah banyak dieksplorasi sebagai katalis karena aktivitas yang baik dan selektivitas tinggi yang sangat bergantung pada bentuk dan ukurannya. Pada umumnya, nanokatalis emas dibuat dalam suatu larutan, dalam penelitian ini kami mendemonstrasikan nanokatalis emas yang ditumbuhkan langsung pada substrat kaca yang dilapisi ITO melalui metode seed-mediated growth. Bentuk dan ukuran nanokatalis emas dimanipulasi oleh komposisi surfaktan b-cyclodextrin dan DTAB.Hasil karakterisasi FESEM menunjukkan bahwa penggunaan DTAB yang banyak menghasilkan nanopartikel Au berbentuk bulat dan saling bertumpuk tidak teratur, sedangkan dengan menggunakan b-cyclodextrin yang lebih banyak menghasilkan bentuk cauliflowers yang homogen dengan diameter rata-rata 270 nm. Semua sampel bersifat polikristalin face center cubic dengan bidang kristal 111 yang memiliki puncak intensitas tertinggi. Morfologi ini bersesuaian dengan spektrum serapan optiknya yang memiliki puncak Localized Surface Plasmon Resonance.Hasil uji sifat katalitik nanopartikel Au untuk proses hidrogenasi aseton menunjukkan bahwa laju degradasi aseton oleh katalis A, B dan C secara berturut-turut adalah 43 , 46 dan 58 jauh lebih tinggi daripada larutan aseton tanpa katalis yang hanya terdegradasi 25 . Hal ini mungkin disebabkan karena morfologi cauliflowers memberikan area permukaan aktif yang tinggi dan homogen sebagai tempat terjadinya interaksi/ adsorpsi dengan hidrogen dan aseton.

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For a long time, in the earlier report gold was considered to be catalytically inactive. However, since the 1980s the gold based heterogeneous nanocatalyst have been widely explored as potential catalysts because of their good activity and high selectivity that highly depend on their shape and size. Generally, gold nanocatalyst were prepared in a solution, in this study we demonstrate the gold nanocatalysts were grown directly on ITO coated glass substrates via a seed mediated growth method. The shape and size of gold nanocatalysts were manipulated through the composition of surfactants of b cyclodextrin and DTAB.The characterization results of FESEM showed that a large amount of DTAB in the sample produce a spherical and irregularly stacked shape of Au nanoparticles, whereas the sample using a higher amount b cyclodextrin result in homogenous cauliflowers shape with an average diameter of 270 nm. All samples characteristic are poly crystalline face center cubic with the 111 plane has the highest intensity peak. This morphology corresponds to the optical properties that emerge as the Localized Surface Plasmon Resonance absorbtion peak.The results of catalytic properties in Au nanoparticles for the acetone hydrogenation process showed that the rate of acetone degradation by catalysts was 43 , 46 and 58 , much higher than without catalyst which is only 25 . This may be due to the morphology of cauliflowers provides a high active and homogenous surface area as an interaction adsorption sites with hydrogen and acetone."

"The thin film of Indium Tin Oxide (ITO) whose the final thickness between 502 nm - 850 nm, various oxygen partial pressure between 0 - 32 mPa and the deposition rate 1,2 nm/s, 2,2 nm/s and 3,5 nm/s have already made by DC magnetron sputtering method. Having studied about the influence of oxygen partial pressure and deposition rate to electrical property of ITO : resistivity, conductivity, carrier charge concentration, mobility; temperature coefficient and activation energy. Resistivity, conductivity, mobility and carrier charge concentration at room temperature are determined by using Van der Pauw method, and resistivity vs temperature between 12 K -. 300 K to find coefficient temperature and activation energy is used four point probe method.In this thesis , we got resistivity value is in range 3,2 x 10-4 Ω cm - 25,4x 10'Ω cm at room temperature 300 K. Conductivity is in range 294 Ω -' cm-' - 3125 Ω -1 cm-1. Carrier charge concentration is in range 1,30x1020 cm-3 - 3,56 x 1420 cm3. Mobility is in range 19,0 cm2/Vs - 55,2 cm 2/Vs. Temperature coefficient at 150 K - 250 K, where resistivity vs temperature is linier, is in range 1,23 x 10-4 K-1 - 8,68 x 10-4 K-1. and activation energy is in range 1,73x104 eV - 43,2 x10-6 eV. The influence of oxygen partial pressure to electrical properties of ITO is, the bigger oxygen partial pressure, the bigger resistivity, and the smaller carrier charge concentration, mobility and temperature coefficient. The various the deposition rate shows that the faster deposition rate , the bigger resistivity and the smaller conductivity, mobility and carrier charge concentration. Carrier charge concentration is caused by oxygen vacancies and Sn substitution to In. The decreasing of carrier charge concentration as the increasing oxygen partial pressure connect with Sn oxide which made this cause the increasing of scattering.

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Lapisan tipis Indium Tin Oksida (ITO) dengan ketebalan 502 - 850 nm dengan beberapa variasi tekanan parsial oksigen antara 0 sampai 32 mPa dan variasi laju deposisi 1,2 nmis, 2,2 nm/s dan 3,5 nm/s telah berhasil dibuat dengan proses dc magnetron sputtering. Dilakukan studi pengaruh tekanan parsial oksigen dan laju deposisi terhadap sifat listrik yang meliputi : resistivitas, konduktivitas, konsentrasi pembawa muatan, mobilitas, koefisien temperatur dan energi aktivasi pada lapisan tipis ITO. Resistivitas, konduktivitas, mobilitas dan konsentrasi pembawa muatan pada temperatur ruang 300 K diukur dengan metoda Van der Pauw. Sedang pengukuran resistivitas vs temperatur antara 12 K sampai 300 K untuk mendapatkan koefisien temperatur dan energi aktivasi dilakukan dengan menggunakan metoda empat titik.Hasil pengukuran resistivitas berkisar antara 3,2 x 10 Ω cm sampai 25,4x 104 Ω cm pada temperatur ruang 300 K. Konduktivitas didapat dengan rnenginversikan resistivitas didapat 294 Ω-1 cm-1 sampai 3125 Ω-1 cm-1 . Konsentrasi pembawa muatan pada temperatur ruang berkisar antara 1,30 x 1020 cm-3 sampai 3,56 x 1020 cm-3. Mobilitas pada temperatur ruang berkisar antara 19,0 cm 2/Vs sampai 55,2 cm2/Vs. Koefisien temperatur yang dihitung pada temperatur 150 K sampai 250 K yakni daerah dimana resistivitas vs temperatur merupakan fungsi linear didapat antara 1,23 x 10-4K-1 sampai 8,68 x 10-4 K-1. Energi aktivasi didapat antara 1,73x10-6 eV sampai 43,2 x10-6 eV. Pengaruh tekanan parsial oksigen terhadap sifat listrik lapisan tipis ITO adalah semakin besar tekanan parsial oksigen cenderung akan semakin besar resistivitasnya, sedangkan konsentrasi pembawa muatan, mobilitas dan koefisien temperatur semakin kecil. Variasi laju deposisi memberikan bahwa semakin besar laju deposisi cenderung semakin besar resistivitasnya, sedangkan konduktivitas, mobilitas dan konsentrasi pembawa muatan cenderung semakin kecil. Konsentrasi pembawa muatan disebabkan terutama oleh vakansi oksigen dan substitusi Sn terhadap In. Menurunnya konsentrasi pembawa muatan dengan naiknya tekanan parsial oksigen berhubungan dengan berkurangnya vakansi oksigen dengan pemberian oksigen dari luar. Mobilitas menurun dengan kenaikan oksigen berhubungan dengan terbentuknya oksida Sn yang menambah efek hamburan."

"ABSTRAKKaca konduktor memiliki fungsi strategis di berbagai aplikasi elektronik. Jenisyang menjanjikan adalah Fluorine-doped Tin Oxide (FTO). Dalam penelitian inidilakukan studi pengaruh waktu deposisi (5, 10, 20, 30, dan 40 menit) lapisan tipisFTO dengan metode spray pyrolysis menggunakan alat ultrasonic nebulizer yangtelah dimodifikasi terhadap nilai karakteristik lapisannya ditinjau dari sifat optis,kristalinitas, resistivitas, dan mikrostruktur. Variasi juga dilakukan denganmembandingkan prekursor Sn murni dan larutan yang telah didoping dengan Fsebanyak 2%wt untuk melihat pengaruh penambahan doping F pada larutanprekursor. Pengujian karakteristik lapisan dilakukan menggunakan XRD, SEM,UV-Vis spectroscopy, dan digital multimeter. Berdasarkan karakterisasi yangdilakukan diperoleh nilai terbaik untuk FTO yang dihasilkan adalah pada waktudeposisi 20 menit dengan nilai transmitansi 74%, energi band gap (Eg) 3,85 eV,dan sheet resistance (Rs) 7,99 Ω/sq.

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ABSTRACTConductive glass has strategic functions in various electronic applications. Oneof the lead is Fluorine-doped Tin Oxide (FTO). In this research, the effects ofdeposition time (5,10,20,30, and 40 minutes) for fabrication of FTO thin film uponspray pyrolysis process using modified ultrasonic nebulizer on its characteristicin terms of optical, crystalinity, resistivity and microstructure properties has beenstudied. Variation was also performed by comparing the pure Sn precursor andthe solution that has been doped with F 2%wt to see the doping effect toproperties of thin film. The thin film characterization were carried out using XRD,SEM, UV-Vis spectroscopy, and digital mutlimeter. Based on the results obtainedfor the best FTO was generated at the time of deposition is 20 minutes. Providing74% transmittance, band gap energy (Eg) 3.85 eV and sheet resistance (Rs) 7.99Ω/sq."

"ABSTRAKAntimony (Sb) doped tin oxide (ATO) merupakan salah satu material transparan yang telah mendapatkan popularitas lebih akhir-akhir ini karena sangat berperan penting terhadap teknologi. transparansi tinggi pada cahaya tampak, konsentrasi dan mobilitas elektron tinggi membuat ATO sebagai bahan penting untuk oksida transparan konduktif, display flat-panel, sel surya, jendela arsitektur perangkat optoelektronik dan sensor gas. Dalam penelitian ini, lapisan tipis antimony doped-tin oxide (ATO) dibuat dengan biaya rendah dan sederhana menggunakan metode ultrasonic spray pyrolysis. Lapisan tipis ATO telah ditumbuhkan dengan menvariasikan konsentrasi doping antimon (0%, 1%, 2%, 3% Sb) dan waktu deposisi (10, 20, 30 menit). Sifat struktural, morfologi, optik dan listrik dari lapisan ini telah dianalisis dengan difraksi sinar-X, mikroskop elektron, UV-VIS dan instrumen four point probe. Analisis XRD menunjukkan bahwa semua lapisan polikristalin dengan struktur kristal tetragonal. Analisis sifat optik dan listrik menunjukkan bahwa konsentrasi optimum doping Sb telah diperoleh untuk meningkatkan transparansi danmeningkatkan konduktivitas listrik lapisan tipis timah oksida

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ABSTRACTAntimony (Sb) doped tin oxide (ATO) is one transparent material that has gained its popularity more recently due to their great technological importance. High transparency in the visible light, high concentration and mobility of electron makes ATO as an important material for the field of transparent conducting oxide, flat-panel display, solar cell, architectural windows optoelectronic devices and gas sensor. In this study, Sb doped-tin oxide (ATO) thin films has been fabricated by low cost and simple, ultrasonic spray pyrolysis method. ATO thin films have been deposited with various antimony doping concentrations (0%, 1%, 2%, 3% Sb) and time deposition(10, 20, 30 minutes). The structural, morphological, optical and electrical properties of these films have been analyzed by X-ray diffraction, scanning electron microscopy, UV-VIS and four point probe instruments. XRD studies show that all films are polycrystalline with tetragonal crystal structure. The optic and electric properties studies show that the concentration optimum of Sb doping has been obtained to increase transparency and improve the electrical conductivity of tin oxide thin film."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 Ω/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 ?/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"Masalah lingkungan terbesar saat ini adalah polusi udara. Data Intergovernmental Panel on Climate Change (IPCC) pada laporan United Nation Environment Programme 2021 menunjukan emisi gas CO2 yang semakin membesar, sehingga berpotensi meninkatkan pemanasan global 1,50C hingga 20C dalam dua dekade kedepan. Dye-Sensitized Solar Cell (DSSC) berbasis TiO2, sebagai generasi ketiga dari sel surya terus dikembangkan salah satu solusi energi terbarukan. Penelitian ini ditujukan untuk membuat dan mempelajari perangkat DSSC menggunakan semikonduktor TiO2-nanotube yang disintesis menggunakan metode two-step anodization dengan variasi waktu anodisasi pertama 1 jam, 2 jam, dan 3 jam dilanjutkan dengan anodisasi kedua selama 30 menit. Selain itu reduksi juga dilakukan terhadap sebagian TiO2 hasil anodisasi. Karakterisasi dilakukan menggunakan instrumen SEM, FTIR, UV-Vis DRS, UV-Vis dan potensiostat. Material ini kemudian dipadukan dengan ruthenium N719 sebagai sensitizer, Pt/FTO sebagai elektroda counter dan elektrolit I-/I3- dan dilakukan evaluasi kinerja DSSC. hasilnya, diperoleh nilai efisiensi sebesar 2,12%; 3,14%; dan 3,15% untuk variasi anodisasi pertama 1 jam, 2 jam, dan 3 jam tanpa direduksi dan 3,60%; 3,07%; dan 4,29 % untuk variasi 1 jam, 2 jam dan 3 jam yang kemudian direduksi.

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Air pollution is the most pressing environmental problem humans face today. According to findings of the Intergovernmental Panel on Climate Change (IPCC) included in the United Nations Environment Programme's 2021 report, if significant emission reductions are not accomplished, rising CO2 emissions might result in a 1.50C to 20C increase in global temperature over the next two decades. Third-generation solar cells, known as dye-sensitized solar cells (DSSC) based on TiO2, are always being developed as one of renewable energy. This study aimed to create and investigate DSSC devices using TiO2 nanotubes synthesized via a two-step anodization method with variations in the first anodization time of 1 hour, 2 hours, and 3 hours, followed by a second anodization for 30 minutes. In addition, reduction was also performed on a portion of the TiO2 produced from the anodization process. Instruments such as SEM, FTIR, UV-Vis DRS, UV-Vis, and potentiostat were used to characterize the material. For DSSC performance assessment, the material was mixed with I-/I3- as a electrolyte, Pt/FTO as a counter electrode, and ruthenium N719 as a sensitizer. For the 1-hour, 2-hour, and 3-hour initial anodization variations without reduction, the research yielded efficiencies of 2.12%, 3.14%, and 3.15%; for the 1-hour, 2-hour, and 3-hour variations with subsequent reduction, the results showed 3.60%, 3.07%, and 4.29%."