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Indar Kustiningsih
"Titania nanotubes (TiO2 NT) and Titania nanowires (TiO2 NW) were fabricated using TiO2 Degussa P25 (TiO2 P25) nanoparticle as precursors via a sonication-hydrothermal combination approach. The prepared catalysts were characterized by means of an X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), ultraviolet-visible diffuse reflectance spectroscopy (DRS) and the Brunauer-Emmett-Teller technique (BET). The photocatalytic activity of prepared catalysts was evaluated for photocatalytic H2 evolution from an aqueous methanol solution. The results showed that activity of the catalyst not only depends on the morphology of its catalysts, but also on the crystalinity and surface area. Hydrogen production of TiO2 NT was about three times higher than TiO2 P25 and TiO2 NW was two times higher than TiO2P25."
Depok: Faculty of Engineering, Universitas Indonesia, 2014
UI-IJTECH 5:2 (2014)
Artikel Jurnal  Universitas Indonesia Library
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Indar Kustiningsih
"Optimasi berbagai parameter untuk preparasi fotokatalis TiO2 nanotubes dan TiO2 nanowires telah dilakukan, diantaranya dengan kombinasi proses sonikasi dan hidrotermal yang dilanjutkan dengan post treatment (kalsinasi atau hydrothermal post treatment) dan penambahan dopan logam (Cu, Pt) dan dopan nonlogam (N). Karakterisasi terhadap hasil sintesis dilakukan dengan menggunakan analisa TEM, SEM, BET, DRS dan XRD. Dari hasil analisa TEM dan SEM menunjukkan proses kombinasi sonikasi hidrothermal menggunakan NaOH diperoleh morfologi nanotubes dengan diameter luar 40 nm, sedangkan dengan KOH diperoleh struktur nanowires dengan diameter luar sebesar 6 nm. Hasil pengujian XRD menunjukkan fasa kristal baik untuk nanotubes maupun nanowires yang dihasilkan adalah anatase. Uji aktifitas katalis untuk produksi hidrogen menggunakan sacrificial agent metanol.
Dari hasil pengujian menunjukkan modifikasi TiO2 dari nanopartikel menjadi nanotubes dapat meningkatkan produksi hidrogen menjadi dua sampai tiga kalinya, sedangkan modifikasi ke bentuk nanowires menjadi dua kali dibandingkan TiO2 P25. Luas permukaan yang tinggi dan morfologi berongga pada nanotubes menyebabkan dispersi dopan Pt pada TiO2 nanotubes menjadi lebih baik sehingga mampu meningkatkan aktivitas fotokatalis dalam memproduksi hidrogen dari air hingga delapan belas kali lebih tinggi dibandingkan tanpa dopan platina. Pemberian dopan nitrogen pada fotokatalis TiO2 nanotube belum mampu menggeser panjang gelombang absorbansi secara signifikan sehingga dengan sumber foton sinar tampak belum dapat menghasilkan hidrogen yang cukup tinggi.

Optimization of various parameters on the preparation of TiO2 nanotubes and TiO2 nanowires have been conducted, such as combination of sonication and hydrothermal process followed by post-treatment (calcination or hydrothermal post treatment) and the addition of dopant metal (Cu, Pt) and non-metallic dopants (N). The modified catalysts were characterized using TEM, SEM, BET, DRS and XRD. The TEM and SEM analysis showed that the sonication-hydrothermal treatment with aqueous NaOH and KOH lead to the formation of nanotubes and nanowires morphology with an average outer diameter of 40 nm and 6 nm, respectively. XRD analysis showed that the both morphologies have anatase crystalline phase. Performance of the prepared photocatalyst on hydrogen production was examined by using methanol as sacrificial agent.
The results indicated the modification of TiO2 nanoparticles into nanotubes could increased in producing hydrogen two-three fold, while the modification to the nanowires into two fold comparing to that of unmodified TiO2 (P25). Larger surface area and porous morphology in nanotubes enhanced the Pt dopant dispersion on TiO2 NT to increase the photocatalyst activity. Furthermore, this increased the production of hydrogen by 18 fold compared to that of non doped TiO2 nanotubes. However introduction of N dopant to the TiO2 nanotubes was not able to shift the absorbtion band toward visible region. Therefore, the high yield of hydrogen production was not achieved by as prepared N doped TiO2, when visible light was used as the photon source."
Depok: Fakultas Teknik Universitas Indonesia, 2013
D1502
UI - Disertasi Membership  Universitas Indonesia Library
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Desi Heltina
"Titania nanotube (TNT)-carbon nanotube (CNT) composite had been successfully synthesized using simple mixing under acidic conditions and ultrasonic treatment. The samples were further characterized via field emission scanning electron microscopy (FESEM), X–ray diffraction (XRD), diffuse re?ectance UV-vis spectroscopy, and Brunauer-Emmett-Teller (BET) analysis. The TNT–CNT composite’s ability to degrade phenol, a model of industrial waste, was tested. The effects of CNT composition and calcination temperature on the phenol degradation performance of TNT-CNT composite were investigated. The results show that the TNT-CNT composite exhibits higher photocatalytic activity than TNT or CNT alone. The crystallinity of the catalyst is not the only parameter affecting the photocatalytic activity. Rather, the specific surface area, bandgap, and morphology of the catalyst must also be considered."
Depok: Faculty of Engineering, Universitas Indonesia, 2015
UI-IJTECH 6:7 (2015)
Artikel Jurnal  Universitas Indonesia Library
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Ratnawati
"[ABSTRAK
Sintesis TiO2 bermorfologi nanotube array bentuk film (TNTAs) telah dilakukan dengan proses anodisasi logam Ti dalam larutan elektrolit gliserol yang mengandung NH4F, dilanjutkan dengan annealing untuk membuat fasa kristal dari TNTAs. Optimasi berbagai parameter meliputi variasi kadar air dalam larutan elektrolit, perlakuan annealing, penambahan NaBF4, metode dan lama pengadukan serta variasi loading dan metode dalam penambahan dopan logam Pt. Hasil SEM/FESEM menunjukkan bahwa TNTAs berhasil disintesis dengan tube yang rapi, tegak lurus dan mempunyai kisaran diameter dalam antara 49-205 nm, tebal dinding 11-33 nm serta panjang 530-2577 nm. Annealing dengan H2/Ar merupakan cara yang efisien untuk memasukkan dopan C, N dan B dalam matrik TNTAs secara insitu saat anodisasi, sehingga diperoleh penurunan energi band gap sampai pada kisaran 2,20?3,10 eV. Kebanyakan TNTAs berfasa anatase dengan ukuran kristal dari 18?33 nm. TNTAs yang disintesis pada kadar air 25% volume dan annealing dengan 20% H2/Ar merupakan fotokatalis optimal yang menghasilkan kerapatan arus tertinggi. Uji TNTAs untuk memproduksi hidrogen menggunakan gliserol sebagai sacrificial agent. Penambahan 5 mM NaBF4 selama anodisasi menghasilan TNTAs termodifikasi yang mampu menghambat laju rekombinasi elektron-hole sehingga dapat meningkatkan produksi hidrogen sebesar 32 %. Penambahan dopan Pt sebagai electron trapper secara fotodeposisi pada TNTAs hasil anodisasi ultrasonik mampu menghasilkan hidrogen dari larutan gliserol sebesar lima kali lebih tinggi dibandingkan tanpa penambahan Pt.;

ABSTRACT
Synthesis of TiO2 nanotube array (TNTAs) has been performed by anodization process of Ti metal in the glycerol electrolyte solution containing NH4F followed by annealing to induce crystallization. Optimization some parameters was done including the variation of water content in the electrolyte solution, annealing atmosphere, addition of NaBF4, mode of mixing, as well as the variation of loading and the methods of Pt addition on the TNTAs. SEM/FESEM analysis showed that well ordered and vertically oriented of TNTAs with inner diameters of 49-205 nm, wall thicknesses from 11 to 33 nm and lengths from 530 to 2577 nm were synthesized. Annealing with H2/Ar is found to be an efficient method for introducing dopant C, N and B into the lattice of TNTAs via insitu anodization and, therefore, the reducing band gap in the range of 2,20?3,10 eV can be obtained. Most of TNTAs have anatase phase with the crystalline size from 18 to 33 nm. Water content of 25 v% and annealing under H2/Ar of as-synt TNTAs showed optimal condition in producing the highest photocurrent density. The photocatalytic hydrogen production test was performed with glycerol as a sacrificial agent. The addition of 5 mM NaBF4 during anodization resulted modified TNTAs that can reduce recombination of electron-hole and showed up 32 % improvement in hydrogen production. The photodeposition of Pt on the TNTAs that obtained from ultrasonic anodization can enhance hydrogen production five times higher compare to the one with unplatinized TNTAs.;Synthesis of TiO2 nanotube array (TNTAs) has been performed by anodization process of Ti metal in the glycerol electrolyte solution containing NH4F followed by annealing to induce crystallization. Optimization some parameters was done including the variation of water content in the electrolyte solution, annealing atmosphere, addition of NaBF4, mode of mixing, as well as the variation of loading and the methods of Pt addition on the TNTAs. SEM/FESEM analysis showed that well ordered and vertically oriented of TNTAs with inner diameters of 49-205 nm, wall thicknesses from 11 to 33 nm and lengths from 530 to 2577 nm were synthesized. Annealing with H2/Ar is found to be an efficient method for introducing dopant C, N and B into the lattice of TNTAs via insitu anodization and, therefore, the reducing band gap in the range of 2,20?3,10 eV can be obtained. Most of TNTAs have anatase phase with the crystalline size from 18 to 33 nm. Water content of 25 v% and annealing under H2/Ar of as-synt TNTAs showed optimal condition in producing the highest photocurrent density. The photocatalytic hydrogen production test was performed with glycerol as a sacrificial agent. The addition of 5 mM NaBF4 during anodization resulted modified TNTAs that can reduce recombination of electron-hole and showed up 32 % improvement in hydrogen production. The photodeposition of Pt on the TNTAs that obtained from ultrasonic anodization can enhance hydrogen production five times higher compare to the one with unplatinized TNTAs., Synthesis of TiO2 nanotube array (TNTAs) has been performed by anodization process of Ti metal in the glycerol electrolyte solution containing NH4F followed by annealing to induce crystallization. Optimization some parameters was done including the variation of water content in the electrolyte solution, annealing atmosphere, addition of NaBF4, mode of mixing, as well as the variation of loading and the methods of Pt addition on the TNTAs. SEM/FESEM analysis showed that well ordered and vertically oriented of TNTAs with inner diameters of 49-205 nm, wall thicknesses from 11 to 33 nm and lengths from 530 to 2577 nm were synthesized. Annealing with H2/Ar is found to be an efficient method for introducing dopant C, N and B into the lattice of TNTAs via insitu anodization and, therefore, the reducing band gap in the range of 2,20–3,10 eV can be obtained. Most of TNTAs have anatase phase with the crystalline size from 18 to 33 nm. Water content of 25 v% and annealing under H2/Ar of as-synt TNTAs showed optimal condition in producing the highest photocurrent density. The photocatalytic hydrogen production test was performed with glycerol as a sacrificial agent. The addition of 5 mM NaBF4 during anodization resulted modified TNTAs that can reduce recombination of electron-hole and showed up 32 % improvement in hydrogen production. The photodeposition of Pt on the TNTAs that obtained from ultrasonic anodization can enhance hydrogen production five times higher compare to the one with unplatinized TNTAs.]"
2015
D2057
UI - Disertasi Membership  Universitas Indonesia Library
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Raudina
"Degradasi 2,4,6-Triklorofenol dalam limbah cair batubara dan produksi hidrogen secara simultan telah dilakukan dengan menggunakan berbagai katalis yaitu TiO2-P25, Titania Nanotube TiNT serta nanokomposit TiNT-Graphene dengan variasi loading graphene. Nanokomposit TiNT-Graphene berhasil disintesis dengan metode hidrotermal dan sonikasi serta dikarakterisasi dengan UV-Vis DRS, XRD, SEM/EDX/Mapping, BET dan FT-IR. Hasil karakterisasi UV-Vis DRS menunjukkan adanya penurunan band gap pada nanokomposit TiNT-Graphene. Hasil XRD menunjukkan fasa anatase pada TiNT dan nanokomposit dengan fraksi 100. SEM/EDX/Mapping menunjukkan adanya kandungan material TiNT dan graphene dalam morfologi dan komposisi nanokomposit dengan persebaran yang merata.
Hasil karakterisasi BET menunjukkan bahwa nanokomposit memiliki luas permukaan yang tinggi sebesar 134,2 m2/g. Namun, tidak terbentuk ikatan Ti-O-C yang ditandai dari hasil karakterisasi FT-IR. Nanokomposit yang optimal diperoleh pada loading graphene 0,6 yang pada sistem simultan dapat mengonversi 2,4,6-Triklorofenol sebesar 89 12 lebih besar dari TiO2-P25 dan memproduksi hidrogen sebesar 986 ?mol 1,7 kali lebih banyak dari TiO2-P25 . Degradasi 2,4,6-Triklorofenol secara kinetika dapat dimodelkan dengan baik menggunakan persamaan reaksi orde satu untuk konsentrasi awal 2,4,6-Triklorofenol maksimal 10 ppm. Hasil uji juga menunjukkan penambahan 2,4,6-Triklorofenol sebesar 50 ppm dapat meningkatkan produksi hidrogen sebesar 626 ?mol 2,7 kali lebih besar.

Degradation of 2,4,6 Trichlorophenol in coal liquid waste and hydrogen production simultaneously has been tested using catalysts such as TiO2 P25, Titania Nanotube TiNT and TiNT Graphene nanocomposite with graphene loading variation. TiNT Graphene nanocomposite were synthesized using hydrothermal and sonication method and were characterized using UV Vis DRS, XRD, SEM EDX Mapping, BET and FT IR. UV Vis DRS characterization showed a band gap reduction in TiNT Graphene nanocomposite. SEM EDX Mapping characterization result indicated the presence of TiNT and graphene material in nanocomposite rsquo s morphology and composition with equal distribution.
BET characterization result showed that the nanocomposite has a high surface area of 134,2 cm2 g. However, there was no Ti O C bond in nanocomposite that showed in FT IR characterization. Optimal graphene loading of 0.6 was obtained in the simultaneous system with 89 elimination of 2,4,6 Trichlorophenol 12 greater than TiO2 P25 and 986 mol of hydrogen production 1.7 times greater than TiO2 P25 . 2,4,6 Trichlorophenol degradation could be kinetically model by using first order reaction equation for 2,4,6 Trichlorofenol concentration of maximum 10 ppm. Test results also showed that 50 ppm addition of 2,4,6 Trichlorophenol would subsequently enhanced hydrogen production by 626 mol 2.7 times greater.
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Depok: Fakultas Teknik Universitas Indonesia, 2017
S67931
UI - Skripsi Membership  Universitas Indonesia Library
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Agung Siswahyu
"Penambahan nanopartikel kedalam fluida dasar dapat meningkatkan konduktivitas panas fluida dasar, sistem seperti ini disebut dengan nanofluida. Penelitian ini memiliki fokus untuk meningkatkan konduktivitas termal fluida dasar dan kestabilannya, pengujian dilakukan dengan portable thermal conductivity meter, particle size analyzer dan heat pipe. Nanofluida berbahan dasar TiO2 mengalami kenaikan konduktivitas termal terbesar pada penambahan 8%v TiO2, pH 8 dan penggunaan surfaktan CTAB sebesar 4 x cmc. Hasil pengujian menunjukkan nanofluida TiO2 meningkat konduktivitas termalnya 21% dari fluida dasarnya, dan nanofluida dengan penambahan surfaktan mampu menekan laju pengendapan terlihat dari ukuran partikel sebesar 196 nm dan intensitas 98,3% serta mampu menurunkan temperatur dievaporator heat pipe sebesar 36% dari fluida dasarnya.

The addition of nanoparticles into the base fluid can increase the thermal conductivity of the base fluid, the system is called the nanofluida. This research has focused on improving the base fluid thermal conductivity and stability, testing was conducted with a portable thermal conductivity meter, particle size analyzer and the heat pipe. Nanofluida TiO2-based had the largest increase in thermal conductivity on the addition of 8% v TiO2, pH 8, and the use of CTAB surfactant by 4 x cmc. Test results showed nanofluida TiO2 increased thermal conductivity of the fluid is essentially 21%, and with the addition of surfactant nanofluida able to suppress the deposition rate can be seen from the particle size of 196 nm and the intensity of 98.3% and can lower the temperature in the evaporator heat pipe by 36% of the base fluid.
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Depok: Fakultas Teknik Universitas Indonesia, 2013
T32915
UI - Tesis Membership  Universitas Indonesia Library
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Febrian Tri Adhi Wibowo
"Komposit CNT-TiO2 untuk dilapiskan pada diaper telah disintesis dan diuji kinerjanya untuk penyisihan ammonia dan jamur Candida albicans sebagai penyebab bau dan kandiasis pada diaper. Komposit dikarakterisasi dengan FTIR, FESEM-EDX, XRD, dan UV-Vis DRS. Hasil Karakterisasi menunjukkan bahwa komposit memiliki kristalinitas tinggi dan band gap rendah.
Hasil uji penyisihan menunjukkan bahwa komposisi komposit optimum adalah 1-3% massa CNT dan 97-99% massa TiO2. Treatment asam CNT dan pembuatan komposit pada pH 1 menggunakan sonikator merupakan teknik pembuatan yang optimum. Penyisihan ammonia selama 2 jam berhasil mendegradasi 91% ammonia. Penyisihan jamur dengan TiO2 P25 berhasil mendisinfeksi 98% jamur selama 2 jam.

CNT-TiO2 composite that is coated on diaper had been synthesized and used for ammonia and Candida albicans removal that cause odor and Candidiasis on diaper. Composite was characterized by FTIR, FESEM-EDX, XRD, and UV-Vis DRS. Result of characterizations show that composite has high crystallinity and low band gap.
Result of removal experiment show that the optimum composition of composite were 1-3% mass of CNT and 97-99% mass of TiO2. Acid treatment CNT and synthesize of composite in pH 1 by using sonicator is an appropriate synthesize. Ammonia removal had been done for two hours and reached 91% degradation of ammonia. Disinfection by TiO2 P25 had reached 98% disinfection of yeast for two hours.
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Depok: Fakultas Teknik Universitas Indonesia, 2014
S55474
UI - Skripsi Membership  Universitas Indonesia Library
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Hendrik
"Carbon Nanotube (CNT) merupakan material multifungsi yang akan dibutuhkan dalam jumlah besar di masa depan. Terdapat metode yang sangat menjanjikan untuk memproduksi CNT dalam jumlah besar yaitu dengan Chemical Vapor Deposition (CVD) dalam reaktor unggun terfluidisasi. Oleh karena itu, penelitian ini difokuskan untuk dapat menghasilkan model reaktor unggun terfluidsasi sehingga dapat dikembangkan menjadi reaktor skala pabrik yang mampu memproduksi CNT dalam skala besar secara efisien. Persamaan peristiwa perpindahan untuk fenomena fisik yang berlangsung dalam reaktor akan dikombinasikan dengan persamaan kinetika reaksi dengan menggunakan Computational Fluid Dynamics (CFD) dalam COMSOL Multiphysics sehingga dihasilkan sebuah model reaktor. Selanjutnya model akan disimulasikan dengan variasi parameter proses.
Hasil simulasi menunjukkan bahwa profil konsentrasi metana dipengaruhi oleh suhu dinding reaktor, rasio umpan, laju alir gas, tekanan umpan, dan ukuran katalis. Konversi metana dan yield karbon meningkat seiring dengan peningkatan suhu dinding reaktor, kandungan hidrogen dalam umpan, dan kecepatan fluida di dalam reaktor. Sedangkan konversi metana menurun seiring meningkatnya tekanan umpan dan ukuran katalis. Konversi metana pada model reaktor unggun terfluidisasi yang disimulasikan adalah sebesar 77% dengan Yield CNT yang dihasilkan sebesar 0.66 gCNT/gCat dalam waktu reaksi selama 5 jam.

Carbon Nanotube (CNT) is well known material having an unique properties and will become future materials. Promising way to synthesize a large scale of CNT is through the Chemical Vapor Deposition in fluidized bed reactor. Focus of this research is to get fluidized bed reactor model which representate the condition and performance in the real reactor. Method of this research is develop model of mathematic equation based on mass, momentum, and energy balance. COMSOL Multiphysics is used to develop the model and for running simulation for several process parameter such as temperature, pressure, etc.
The simulation results show that the methane concentration profile is influenced by the temperature of the walls of the reactor, the feed ratio, gas flow rate, feed presure, and radius of catalyst particles. Conversion of methane and carbon yield increases with increasing temperature of the reactor wall, the addition hydrogen in reactant and the velocity of the fluid in the reactor. Conversion of methane decreases with increasing of feed pressure and radius of catalyst particles. In this model, conversion of methane was about 77% and Yield of CNT was about 0.66 gCNT/gCat for 5 hours of reaction.
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Depok: Fakultas Teknik Universitas Indonesia, 2016
S63460
UI - Skripsi Membership  Universitas Indonesia Library
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