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"Influences of fluorine containing compounds TiF4and ZrF4 on hydrogen sorption properties ofLiBH4 have been investigated. Thermovolumetric measurements, titration, and XRD techniquewere used to characterize the samples. The results demonstrated a pronounced beneficial effectof both ZrF4 and TiF4on the sorption properties of modified LiBH4. After hydrogenation at400°C and 80 bar, formation of modified LiBH4was observed as a consequence of F dissolution in LiH (LiH1-zFz). Adding TiF4 and ZrF4 to LiBH4 has been found to modify boththermodynamic and kinetic properties."

"Influences of fluorine containing compounds TiF4 and ZrF4 on hydrogen sorption properties of LiBH4 have been investigated. Thermovolumetric measurements, titration, and XRD technique were used to characterize the samples. The results demonstrated a pronounced beneficial effect of both ZrF4 and TiF4 on the sorption properties of modified LiBH4. After hydrogenation at 400°C and 80 bar, formation of modified LiBH4 was observed as a consequence of F dissolution in LiH (LiH1-zFz). Adding TiF4 and ZrF4 to LiBH4 has been found to modify both thermodynamic and kinetic properties."

"This volume introduces a variety of viable electrochemical methods to identify reaction mechanisms and evaluate relevant kinetic properties of insertion electrodes. The authors also outline various ways to analyze anomalous behaviour of hydrogen/lithium transport through insertion electrodes. "

"Boron triazin dengan doping lithium serta karbon nitride merupakan material modifikasi dari CNT, lebih baik dari massa zat maupun kemampuan mengadsorp hidrogen. Penelitian mengenai adsorpsi hidrogen oleh material nanostruktur seperti CNT yang dilakukan secara eksperimental serta simulasi memilki banyak kekurangan. Artificial Neural Network dimodelkan sebagai alat prediksi kapasitas adsorpsi hidrogen yang menjadi solusi kekurangan metode penelitian yang ada. Tujuan penelitian ini mencari pengkonfigurasian terbaik untuk ANN sehingga dapat menjadi alat prediksi yang presisi dan teruji jalan cepat mendapatkan data adsorpsi hidrogen tanpa melakukan simulasi. Goal dari penelitian ini ialah mendukung percepatan pengimplementasian hidrogen sebagai renewable energy untuk kapal masa depan. Penelitian dilakukan dengan simulasi struktur nano pada ruang penyebaran hidrogen (VMD, Packmol, Lammps), pengolahan data banyak (Ms.Excel), dan training data (NN). Pemodelan fungsi prediksi ANN pada adsorpsi Hidrogen oleh Boron triazin dengan doping Lithium menghasilkan konfigurasi nn terbaik yakni pada varian pemilihan pertama dengan neuron 10. Sementara untuk Material Triazin pada temperature 77 menghasilkan konfigurasi nn terbaik pada skala 100-1000, pemilihan pertama, neuron 10. Sedangkan pada temperature 233 konfigurasi nn terbaik ditunjukan pada 100-10000 dengan neuron yang sama yakni 10.

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Boron triazine with lithium doping and carbon nitride is a material modification of the CNT, better than the mass of a substance as well as the ability adsorbing hydrogen. Research on hydrogen adsorption by nanostructured materials such as CNT conducted experimental and simulation has many shortcomings. Artificial Neural Network is modeled as predictors of hydrogen adsorption capacity of the solution to be no shortage of research methods.

The purpose of this study look for the best configuration to ANN that can be a predictor of precision and proven fast way to get hydrogen adsorption data without doing simulations. Goal of this study is to support the accelerated implementation of hydrogen as a renewable energy for future ships. The study was conducted with a simulation of nanostructures in space deployment of hydrogen (VMD, Packmol, Lammps), many data processing (Ms.Excel), and the training of data (NN).

ANN predictive modeling function on hydrogen adsorption by Boron doping triazine with Lithium produce the best nn configuration variant first election to the neuron 10. While for Material Triazines at temperatures of 77 to produce the best nn configuration on a scale of 100-1000, the first election, the neuron 10. Meanwhile, at temperatures of 233 nn configuration best shown in 100-10000 the same neurons that is 10."

"ABSTRAKDesertasi ini membahas tentang karakteristik Paduan Mg3CoNi2 Sebagai Penyerap Hidrogen. Paduan dibuat dengan metode pemaduan mekanik. Untuk mendapatkan sampel yang optimal telah dilakukan variasi pembuatan sample dengan mengombinasikan rasio berat bola terhadap sampel 1:1 dan 8:1 dengan waktu milling selama 10 menit, 5, 10, 15, 20, 30, 40 dan 60 jam. Peralatan milling adalah konvensional milling dan High Energy Milling SPEX 8000. Dari pengukuran XRD diketahui bahwa semua sampel mengalami oksidasi dengan bertambahnya waktu milling yaitu terbentuknya fasa MgO yang semakin banyak. Untuk mengurangi oksidasi dilakukan teknik pemaduan basah dengan cara menambahkan toluen ke dalam sampel yang akan dimilling. Dari pengukuran XRD diketahui bahwa fasa yang terbentuk sebagian besar adalah Mg2Ni dan sedikit MgNi2 sedangkan fasa Mg2Co dan MgCo2 tidak terbentuk. Hal ini karena energi pembentukan Mg2Co dan MgCo2 lebih besar dari pada pembentukan Mg2Ni dan MgNi2. Fasa Mg2Ni yang terbentuk mengalami penurunan parameter kisi dari 5,22 nm menjadi 4,59 nm dan dari 13,29 nm menjadi 11,72 nm. Dari hasil pengamatan dengan SEM juga menunjukkan pengurangan ukuran partikel dan dari pengamatan dengan SANS menunjukkan penambahan luas permukaan. Kapasitas penyerapan hidrogen terbanyak diperoleh pada sampel yang dimilling selama 40 jam pada temperatur 200_C, yaitu sebesar 3,3 % berat. Keberadaan hidrogen di dalam sampel ditunjukkan dengan terjadinya perubahan ukuran kristal pada sudut 40,95_ dan pada sudut 47,7_. Keberadaan hidrogen dalam sampel juga dibuktikan dengan turunnya intensitas hamburan neutron pada pengamatan dengan menggunakan SANS.

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ABSTRACTThis dissertation is discussing about the characteristics of Mg3CoNi2 alloy as a hydrogen storage. The alloy is made by mechanical alloying method. To obtain the optimal sample, a variation making of sample has been done by combining the ball to the sample weight ratio of 1:1 and 8:1 with the milling time of 10 s, 5, 10, 15, 20, 30, 40 and 60 hours. The milling apparatus used is a conventional milling and a High Energy Milling SPEX 8000. From the XRD measurement results it is known that all obtained by dry preparation method sample are oxidized into MgO phase, especially for longer milling time. To reduce the oxidation effects a wet alloying method has been done by adding toluene to the sample to be milled. From the XRD measurement results it is known that the phases formed are mostly Mg2Ni and small amount of MgNi2, while the phases of Mg2Co and MgCo2 are not formed. This is because the energy of Mg2Co and MgCo2 formations are bigger than those for Mg2Ni and MgNi2 formation. The lattice parameters of Mg2Ni formed decrease from 5,22 nm to 4,59 nm and from 13,29 nm to 11,72 nm. From the observation results using SEM the decrease of particle size is also shown and from SANS investigations it is shown that surface area increased with increasing milling time. The highest hydrogen absorption capacity was obtained from 40 hours milled sample at hydriding temperature of 200_C. The presence of hydrogen in the sample is indicated the change of the crystallite size calculated the angle of 40,95_and 47,7_. The presence of hydrogen in the sample is also proven with the decrease of neutron scattering intensity analyzed using SANS."

"The potential of carbon nanotubes (CNTs) produced in our laboratory to be used for hydrogen storage was tested in this study. The test includes the determination of the hydrogen gas adsorption capacity and the dynamics of the adsorption and desorption of hydrogen on CNTs at isothermal temperature of 25oC and pressures of 0–1,000 psia. A similar test was also conducted on commercial CNTs obtained from the Chinese Academy of Sciences for comparison. The results showed that the hydrogen adsorption capacity of the local CNTs is lower than that of commercial CNTs. At pressures around 960 psia, the adsorption capacities of local and commercial CNTs are 0.09% and 0.13% weight, respectively. In general, the hydrogen adsorption data of both the adsorbents can be represented well by the Langmuir model, with less than 3% absolute average deviation (AAD). The dynamics of adsorption and desorption can be represented well by the Gasem and Robinson model with less than 2% AAD. The adsorption and desorption processes on both local and commercial CNTs occurred very quickly. At the highest pressure (960 psia), the adsorption and desorption equilibriums on the local CNTs were reached in approximately 30 s, while on commercial CNTs, they were reached in 2 s. The rates of the adsorption equilibriums on both local and commercial CNTs increase at a higher pressure. In the desorption process, while the equilibrium time is reached slightly faster at a higher pressure on commercial CNTs, the time is almost similar at all pressures for local CNTs."

"Proton Exchange Membrane Fuel Cell (PEMFC) merupakan salah satu jenis energi alternatif fuel cell yang sangat potensial untuk menggantikan energi fosil yang semakin terbatas jumlahnya. PEMFC ini memiliki daya yang cukup besar, efisiensi dan densitas arus yang tinggi, serta ramah lingkungan. Oleh karena itu, PEMFC ini banyak digunakan dalam aplikasi peralatan portable seperti Chemical Energy Car yang merupakan prototipe mobil berbahan bakar dari energi kimia. Salah satu kendala dalam penggunaan PEMFC pada peralatan portable adalah mengenai penyimpanan gas hidrogen. Untuk aplikasi tersebut, diperlukan media penyimpanan gas hidrogen yang mudah dalam penyimpanan dan penanganannya. Salah satu alternatifnya ialah dengan menggunakan NaBH4. Melalui proses hidrolisis Sodium borohidrida, hidrogen dapat terbentuk dengan bantuan sedikit katalis.Pada penelitian ini, pembelajaran akan dipusatkan pada perancangan dan fabrikasi seluruh komponen - komponen Chemical Energy Car serta pengaturan kebutuhan reaktan (hidrogen dan oksigen) untuk Chem E Car. Adapun tahapan penelitian yang diusulkan meliputi: reaksi hidrolisis NaBH4 dengan bantuan katalis CoCl2 untuk menghasilkan gas hidrogen , perancangan seluruh komponen Chem E Car, fabrikasi cell stack PEMFC, fabrikasi Membrane Electrode Assembly (meliputi tahap pembuatan tinta katalis, tahap coating tinta katalis, preparasi membran Nafion, serta Hot Press MEA), fabrikasi tempat penyimpanan hidrogen, fabrikasi kerangka mobil, perakitan seluruh komponen - komponen Chem E Car, serta pengujian Chem E Car secara keseluruhan.Reaksi hidrolisis sodium borohidrida ini memiliki orde reaksi 0 yang menunjukan bahwa laju reaksi hanya dipengaruhi oleh konstanta kecepatan reaksinya. Semakin tinggi konsentrasi katalis Cocl2 yang digunakan maka konstanta kecepatan reaksi akan semakin besar. Hubungan tersebut dapat dilukiskan dalam persamaan k = 0.0509 Cc - 0.011. Kebutuhan gas hidrogen untuk PEMFC yang telah difabrikasi relatif kecil sekitar 0.06 ml/s karena dengan luasan MEA 36 cm2, PEMFC hasil fabrikasi hanya dapat menghasilkan densitas arus sebesar 24.25 mA/cm2 dan densitas daya sebesar 5.8 mW/cm2. Dengan daya tersebut Chem E Car dapat bergerak tanpa beban dengan kecepatan 0.083 m/s . Massa Chemical Energy Car keseluruhan tanpa beban adalah 1100 gram ( 245 gram pelat bipolar, 245 gram pelat penutup, 120 gram baut, serta 500 gr untuk kerangka mobil dan reaktor hidrogen).

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Proton Exchange Membrane Fuel Cell (PEMFC) is one kind of fuel cell as an alternative energy that is potential to substitute fossil fuel that has limitation. Using PEMFC as a energy source for Chem E Car due to the power that it produces is high enough, efficient, high current density, and ecological. Therefore, this PMFC mostly used in portable application such as Chemical Energy Car, a prototype car using chemical energy for its fuel. But, this PMFC has a problem if it uses for portable application, it needs hydrogen storage that is easy in handling and storing. Alternative for that problem is to use NaBH4. Hydrogen can be produced through hydrolysis reaction of Sodium Borohydride in addition of catalyst.

This research only focused on designing and fabricating all the Chemical Energy Car's components and managing reactants needs (Hydrogen and Oxygen) for Chemical Energy Car. The research phases done are: hydrolysis reaction of NaBH4 to produce hydrogen in addition of CoCl2 as a catalyst, design of all the Chem E Car components, cell stack fabrication, membrane electrode assembly (MEA) (including the making of catalyst ink, coating, nafion membrane preparation, and hot press MEA), hydrogen storage fabrication, Chem E Car components assembly, and overall test of the Car.

As a result, hydrolysis reaction of Sodium Borohydride has zero order that shows the reaction rate influenced by reaction rate constant. Higher the concentration of the catalyst used higher the reaction rate constant. The relation of that can describe on this formula k = 0.0509 Cc - 0.011. Reactant needed for PEMFC is 0.06 ml/s (MEA 36 cm2). This PEMFC can produce current density in value of 24.25 mA/cm2 and power density in value of 5.8 mW/cm2. With this power, Chem E Car can move 0.083 m/s without charge. The mass total Chem E Car is 1,110 g (245 g for bipolar plate, 245 gram for end plate, 120 gram for bolt, and 500 gram for the car's body and hydrogen reactor)."

"Penggunaan gas hidrogen sebagai sumber energi pada sel bahan bakarmenjadikannya sebagai potensi sumber energi di masa depan Salah satu permasalahan yang cukup perlu diperhatikan pada pemanfaatan hidrogen sebagai sumber energi ini adalah media penyimpanannya Untuk dapat menyimpan hidrogen dalam jumlah besar diperlukan tekanan operasi yang sangat tinggi dan temperatur yang sangat rendah Penyimpanan hidrogen dapat ditingkatkan dengan pemanfaatan fenomena adsorpsi gas hidrogen pada media berporos seperti Carbon Nanotube CNT Kapasitas adsorpsi hidrogen pada CNT ini juga dapat ditingkatkan dengan menyisipkan unsur doping pada CNT Salah satunya adalah dengan menyisipkan senyawa alkali metal seperti Lithium Simulasi dinamika molekuler proses adsorpsi hidrogen pada CNT dengan Lithium sebagai unsur doping ini memberikan perkiraan bahwa kapasitas adsorpsi hidrogendapat meningkat hingga 100 dibandingkan dengan kapasitas adsorpsi hidrogen pada CNT tanpa doping Lithium pada tekanan 40 atm dan temperatur 293 K dari sebelumnya 1 wt menjadi 2 wt

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The uses of hydrogen gas as energy resources in fuel cell let it to be future energy resources potential One of the problems which need to be concerned about the uses of hydrogen gas as energy resources is its storage medium To be able to store hydrogen gas in large amount very high operational pressure and very low operational temperature are required Hydrogen storage capacity can be improved by using adsorption phenomena of hydrogen gas on porous medium like Carbon Nanotube CNT Hydrogen adsorption capacity of CNT can be improved too by inserting alkaline metal such as Lithium into CNT Molecular dynamic simulation of hydrogen adsorption process on Lithium doped CNT predicts that its hydrogen adsorption capacity can be improved until 100 compared to its hydrogen adsorption capacity without Lithium at pressure of 40 atm and temperature of 293 K from 1 wt become 2 wt"

"In this paper, we perform combination methods of semi-empirical research, a theoretical approach, and force-matching to determine the optimum adsorption capacity on an open-ended single-walled carbon nanotube (SWCNT) as a diameter function. Using a semi-empirical study, we can determine the value of monolayer coverage and isosteric heat of adsorption from available thermodynamic data. By completing the semi-empirical study, we carried out quantum mechanical calculations to determine the adsorption energy on the interior and exterior of SWCNTs. Furthermore, monolayer coverage, specific surface area, and maximum adsorption capacity as the main quantity in the adsorption process was estimated using the combination method of force-matching and a classical Lennard-Jones potential model. Hydrogen physisorption was investigated on zig-zag SWCNTs at conditions for a pressure range of 0.1 to 10 MPa at 233 K and 298.15 K temperature. The adsorption of all data can be explained with the Toth model. The results shows the SWCNT exterior physisorption energy range between 1.35 to 1.62 kcal/mol. The interior range from 1.22 to 2.43 kcal/mol. With a wide degree of temperature and pressure variations, we obtained an optimum SWCNT diameter of 8-12 Å . At the optimum diameter maximum adsorption capacity, we achieved 1.75 wt% at 233 K and an operating pressure of 10 MPa."