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Abstrak :
Effects of additing 1 percent (w/o) palladium (Pd) on the thermal behavior of a lathe cut type high copper amalgam (13 w/o copper) were studied. The identical alloys, with and without 1% Pd were fabricated. X-ray diffraction studies of the amalgams revealed the elimination of the y2-phase by Pd addition. DSC thermogram of non-Pd containing amalgam indicated the existence of two y1-phasesone with the transition temperature (endothermic peak) at 88°C and the other at 109°C. The thermogram data of the Pd containing amalgam showed an endothermic peak at 110,7°C. The transition temperature of the n phase of the palladium containing amalgam is 4,9°C lower than the transition temperature of the n phase of the non Pd containing amalgam. This result indicates that the n phase of the Pd containing amalgam includes more of Tin (Sn) than the non-Pd containing amalgam. The thermogravimetri diagram showed that the phase decomposition occured at about 390°C for the non-Pd containing amalgam and at about 410°C for the Pd containing amalgam. It's concluded that the addition of 1% Pd into a lathe cut type of high copper amalgam (13%) could eliminate the formation of y2 phase as well as an unstable y1 phase, promoting strong mercury bonding to silver.

Abstrak :
Kompleks Paladium terutama banyak digunakan sebagai katalis dalam bidang industri dan obat antikanker Penelitian ini bertujuan untuk mempelajari sintesis, karakteristik spektra, dan kegunaan senyawaan kompleks Paladium(II) dengan 2,2'-bipiridin (DPY) dan 2,9~dimeti|-1,10-fenantrolin (fen) sebagai katalis pada aikoholisis urea. Senyawaan kompleks Pa|adium(II) dengan bpy dan fen masing-masing disintesis dengan perbandingan 1:1 dan 1:2 Serta dikarakterisasi menggunakan spektrofotometer uitraungu-tampak dan inframerah. Selain itu, senyawaan kompleks dengan perbandingan 1:1 diaplikasikan sebagai katalisator pada alkohoiisis urea. Kompleks Pd(bpy)CI2 berwama kuning tua, sedangkan kompleks [Pd(bpy)2]Cl2 berwama kuning. Kompleks [Pd(fen)(H;0)2](C|04)2 berwarna coklat muda, sedangkan kompleks [Pd(fen)2](C|04)2 berwarna putih bening. Puncak serapan IE--HC* untuk ligan bpy terkompleks bergeser ke arah panjang gelombang Iebih besar daripada bpy bebas, sedangkan untuk Iigan fen terkompleks bergeser ke arah panjang gelombang Iebih kecil dibandingkan fen bebas. Serapan transisi d->d untuk kompleks Pd(II) dengan bpy terjadi pada panjang gelombang sekitar 373 nm dan dua puncak serapan transisi tersebut untuk kompleks Pd(II) dengan fen terjadi pada panjang gelombang antara 301 sampai 337 nm. Spektra senyawa kompleks Pd(II) dengan bpy pada frekuensi antara 199 sampai 245 om" memperlihatkan dua puncak serapan baru yang menandakan adanya ikatan antara ion Pd(II) dengan ligan akibat pengompleksan. Spektra inframerah ligan bpy dan fen terkompleks pada frekuensi 400-4000 cm°? menunjukkan adanya pergeseran vibrasi ulur C=N dan C=C, serta vibrasi tekuk C-H ke arah frekuensi yang Iebih besar daripada bpy bebas. Kompleks Pd(ll) dengan ligan dalam perbandingan 1:1 dapat dimanfaatkan sebagai katalis dalam alkoholisis urea. Tempat koordinasi yang diisi oleh ligan lemah dapat digantikan oleh urea. Urea yang terikat sebagai ligan akan bereaksi dengan metanol membentuk ester karbamat melaiui metanolisis. Ester karbamat ini akan terdisosiasi secara cepat dan kompleks kembali ke bentuk semula.

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Abstract
Complexes of Palladium are widely used as catalyst in industry and anticancer drugs. The aims of this research were to study of synthesis, spectra characteristic and preliminary test of complexes of Palladium(II) with 2,2'-bipyridine(bpy) and 2,9-dimethyl-1,10-phenanthroline (fan) for catalyst in urea alcoholysis. Complexes of Pd(ll) with bpy and fen were synthesized with 1:1 and 1:2 ratio, respectively and there were characterized with UV-We and IR spectrophotometers. Complex compounds with 1:1 ratio were applicated as catalyst in urea alcoholysis complex of [Pd(bpy)Cl2] is yellow, while complex of [Pd(bpy)2]Cl2 is dark yellow. Complex of [Pd(fen)(H2O)2](Cl04)2 is brown, while complex of [Pd(fen)2](CIO4)2 is white-Peaks of absorption cause of 1:->1r* transition for bpy complex is shifted to higher wavelength than of free bpy, while for fen complex are shifted to lower wavelength than free fen. Absorptions d->d transition for complex of Pd(II) with bpy occurs about 373 nm and two peaks of those transition for complex of Pd(ll) with fen occurs between 301 until 337 nm. Spectra of complexes of Pd(ll) with bpy between 199 until 245 cm" showed two peaks. infrared spectra of bpy and fen complexed in frequency 400-4000 cm" showed a shift C=N and C=C vibrations and C-H vibration to higher frequency than free ligand. Complexes of Pd(Il) with 1:1 ratio can used as catalyst in alooholysis urea. Coordination of weak ligand can changed with urea. Urea is bonded as ligan will react with metanol foml ester carbamate via metanolysis Ester carbamate will dissociated fast and complex revert to first form.

Abstrak :
[ABSTRAK
Tujuan dari penelitian ini adalah untuk mengembangkan proses ?green? baru untuk produksi H2O2 melalui rute sintesis langsung, di mana selama reaksi hidrogen dan oksigen saling kontak satu sama lain. Sebuah pendekatan elektrokimia dengan rotating ring disk electrode (RRDE) telah dieksplorasi dan dikembangkan secara sistematis yang bertujuan untuk mengukur H2O2 yang diproduksi. Dua metode yang berbeda - co-reduction and successive reduction dengan menggunakan microwave diadopsi untuk mempersiapkan bimetal nanocatalysts Pd-Au/C. Hubungan antara struktur nanocatalysts dan aktivitas katalitik dalam proses sintesis langsung diselidiki. Bimetal Pd-Au/C yang telah disintesa, dikarakterisasi dengan ICP-AES, XRD, SEM, TEM, dan XAS untuk pemahaman yang lebih baik dalam aktivitas katalitik sintesis H2O2 secara langsung.

Pendekatan dalam elektrokimia untuk mengukur H2O2 yang dihasilkan dari sintesis langsung telah berhasil dilakukan dengan sistem reaksi 2, dimana katalis tersebar secara homogen dalam larutan. Kurva kalibrasi variasi konsentrasi H2O2 dibuat dalam parameter 0,891 V (vs Ag/AgCl) dan dengan scan rate 50 mV/s. CR Pd3%-Au2%/C yang disintesa oleh co-reduction merupakan optimal loading dengan produktivitas H2O2 65,8 mol.kgcat-1h-1. Produktivitas ini lebih tinggi dari sample katalis lainnya, seperti monometallic Pd0%-Au5%/C & Pd5%-Au0%/C dan bimetal SR Pd-Au/C yang disintesis dengan successive reduction. Produktivitas yang lebih tinggi atau lebih rendah dari satu sampel ke yang lain dijelaskan oleh parameter-parameter seperti ukuran partikel, struktur bimetal Pd- Au/C, bidang kristal yang selektif, dan peran paladium dan emas. Ukuran partikel yang lebih kecil cenderung memiliki Pd yang lebih banyak, sedangkan yang lebih besar cenderung memiliki Au yang lebih banyak. Ukuran partikel yang lebih kecil memiliki daerah permukaan yang lebih tinggi, sehingga produktivitas meningkat. Namun, jika ukuran partikel terlalu kecil, permukaan yang aktif atau bidang kristal yang selektif mungkin sedikit muncul (seperti dapat dilihat dalam SR Pd- Au/C), sehingga produktivitas menurun. vii

Dari analisis XAS, CR Pd-Au/C memiliki struktur Au lebih banyak di core dan Pd lebih banyak di shell. Struktur SR Pd-Au/C di beberapa bagian dari katalis adalah Au lebih banyak di core dan Pd lebih banyak di shell, sementara pada bagian lain, Pd lebih banyak di core dan Au lebih banyak di shell. Nilai Q pada SR PdAu (0,638) lebih tinggi daripada CR PdAu (0,605), yang menunjukkan bahwa keberadaan atom Au di shell SR PdAu lebih dari itu CR PdAu. Perbedaan dalam struktur adalah salah satu alasan mengapa produktivitas H2O2 CR PdAu lebih tinggi dari SR PdAu. Peran Pd adalah untuk memberikan luas permukaan untuk oksidasi selektif dari hidrogen dan peran Au adalah untuk menyediakan situs aktif untuk reaksi dekomposisi dan hidrogenasi H2O2.

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ABSTRACT
The purpose of this study is to develop a new green process for production of H2O2 through the direct synthesis route, of which the hydrogen and oxygen contacts each other during the reaction. An electrochemical approach with the rotating ring disk electrode (RRDE) had been systematically explored and developed accordingly to measure the produced H2O2. Two different methods ? co-reduction and successive reduction prepared in the microwave were adopted to prepare bimetallic Pd-Au/C nanocatalysts. The relationship between the structure of prepared nanocatalysts and their catalytic activity in the direct synthesis process were investigated. As synthesized bimetallic Pd-Au/C were characterized by ICP-AES, XRD, SEM, TEM, and XAS for better understanding in the catalytic activity of direct synthesis of H2O2.

The approach in the electrochemical to measure H2O2 produced from the direct synthesis has been successfully done with the reaction system 2, where the catalyst is dispersed homogenously in the solution. The calibration curve of the different concentration of H2O2 is made in the parameter of 0.891 V (vs Ag/AgCl) and with the scan rate 50 mV/s. The optimum loading of samples prepared by co reduction was observed in CR Pd3%-Au2%/C with the productivity of H2O2 is 65.8 mol.kgcat -1h-1. This productivity is higher than the other prepared catalysts, such as monometallic Pd0%-Au5% & Pd5%-Au0% and bimetallic SR Pd-Au/C that is prepared by successive reduction. The higher or the lower productivity of one sample to another is explained by the parameter of the particle size, the structure of the bimetallic Pd-Au/C, the selective crystalline plane, and the role of palladium and gold. The smaller the particle size tends to Pd rich, while the larger one tends to Au rich. The smaller particle size yielded in the high surface area, thus the productivity increases. However, if the particle size is too small, the active site or selective crystalline plane may be slightly appeared (as can be seen in SR Pd-Au/C), thus the productivity decreases.

From XAS analysis, the structure CR Pd-Au/C is Au rich in core and Pd rich in shell. The structure of SR PdAu at some part of catalyst is Au rich in core and Pd rich in shell, while at the other part, the structure is Pd in core and Au in shell. ix The Q value of SR PdAu (0.638) is higher than that of CR PdAu (0.605), which indicates that the existence of Au atoms in the shell of SR PdAu is more than that of CR PdAu. The difference in their structure is one reason why the H2O2 productivity of CR PdAu is higher than SR PdAu. The role of Pd is to provide the surface area for the selective oxidation of hydrogen and the role of Au is to provide inactive site for the reaction of decomposition and hydrogenation of H2O2., The purpose of this study is to develop a new green process for production of H2O2 through the direct synthesis route, of which the hydrogen and oxygen contacts each other during the reaction. An electrochemical approach with the rotating ring disk electrode (RRDE) had been systematically explored and developed accordingly to measure the produced H2O2. Two different methods – co-reduction and successive reduction prepared in the microwave were adopted to prepare bimetallic Pd-Au/C nanocatalysts. The relationship between the structure of prepared nanocatalysts and their catalytic activity in the direct synthesis process were investigated. As synthesized bimetallic Pd-Au/C were characterized by ICP-AES, XRD, SEM, TEM, and XAS for better understanding in the catalytic activity of direct synthesis of H2O2. The approach in the electrochemical to measure H2O2 produced from the direct synthesis has been successfully done with the reaction system 2, where the catalyst is dispersed homogenously in the solution. The calibration curve of the different concentration of H2O2 is made in the parameter of 0.891 V (vs Ag/AgCl) and with the scan rate 50 mV/s. The optimum loading of samples prepared by co reduction was observed in CR Pd3%-Au2%/C with the productivity of H2O2 is 65.8 mol.kgcat -1h-1. This productivity is higher than the other prepared catalysts, such as monometallic Pd0%-Au5% & Pd5%-Au0% and bimetallic SR Pd-Au/C that is prepared by successive reduction. The higher or the lower productivity of one sample to another is explained by the parameter of the particle size, the structure of the bimetallic Pd-Au/C, the selective crystalline plane, and the role of palladium and gold. The smaller the particle size tends to Pd rich, while the larger one tends to Au rich. The smaller particle size yielded in the high surface area, thus the productivity increases. However, if the particle size is too small, the active site or selective crystalline plane may be slightly appeared (as can be seen in SR Pd-Au/C), thus the productivity decreases. From XAS analysis, the structure CR Pd-Au/C is Au rich in core and Pd rich in shell. The structure of SR PdAu at some part of catalyst is Au rich in core and Pd rich in shell, while at the other part, the structure is Pd in core and Au in shell. ix The Q value of SR PdAu (0.638) is higher than that of CR PdAu (0.605), which indicates that the existence of Au atoms in the shell of SR PdAu is more than that of CR PdAu. The difference in their structure is one reason why the H2O2 productivity of CR PdAu is higher than SR PdAu. The role of Pd is to provide the surface area for the selective oxidation of hydrogen and the role of Au is to provide inactive site for the reaction of decomposition and hydrogenation of H2O2.]

Abstrak :
ABSTRAK
Peningkatan konsentrasi CO2 diatmosfer mengakibatkan permasalahan lingkungan sehingga konversi CO2 menjadi bahan kimia dan bahan bakar menarik untuk dikaji. Salah satu alternatif dalam daur ulang siklus karbon terbarukan yaitu dengan reduksi elektrokatalitik CO2 dapat dilakukan dalam kondisi ruang dan mudah dikontrol proses reaksinya dengan pengubahan potensial. Pada penelitian ini, boron-doped diamond dimodifikasi terlebih dahulu dengan AuNP, PdNP dan AuPdNP kemudian diaplikasikan untuk reduksi CO2 secara elektrokimia. Sebelum dilakukan perendaman dengan larutan nanopartikel, BDD dimodifikasi dengan larutan allilamina dibawah sinar UV selama 6 jam. Kemudian direndam dalam larutan koloid nanopartikel. Karakterisasi larutan nanopartikel dilakukan dengan UV-Vis dan TEM, sedangkan BDD termodifikasi dikarakterisasi dengan SEM EDS, XPS dan secara elektrokimia. Elektroreduksi CO2 dilakukan dalam sel dengan dua kompartemen dengan larutan elektrolit NaCl 0,1 M di dalam ruang katoda dan larutan Na2SO4 0,1 M di dalam ruang anoda. Potensial yang digunakan ialah -0,8 V, -0.9V, dan -1,1V vs Ag/AgCl dengan waktu reduksi selama 60 menit. Produk yang dihasilkan dikarakterisasi dengan GC, HPLC dan GC-MS. Efisiensi Faraday tertinggi dihasilkan oleh elektroda BDDN-AuPdNP sebesar 84,564 dan asam asetat sebagai salah satu produk.Kata kunci: Elektroreduksi CO2, nanopartikel emas palladium, boron-doped diamond, modifikasi permukaan.

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ABSTRACT
The increase of CO2 concentrations in atmosphere can cause an environmental problem so CO2 conversion to chemicals and fuels become interesting to be investigated. One of the alternative in recycling renewable carbon cycles is electrocatlytic conversion of CO2 using the electrochemical method due to mild condition and easily controllable in term of reaction process by changing the potential value. In this study, boron doped diamond was previously modified with AuNP, PdNP and AuPdNP then applied for electrochemical reduction. Before modification with nanoparticle solutions, BDD was modified with allylamine under UV light for 6 hours. The nanoparticle solutions were characterized by UV Vis and TEM, while modified BDD was characterized by SEM EDS, XPS and electrochemical characterization. The electroreduction of CO2 was performed on two cell compartments using NaCl 0,1M in cathode and Na2SO4 in anode. The potentials used were 0.8 V, 0.9V, and 1.1V vs. Ag AgCl with a reduction time of 60 min. The resulting products were characterized by GC, HPLC and GC MS. The highest Faradic efficiency is mostly generated by BDDN AuPdNP electrode, approximately 84.564 and the only electrode form these experiments which had produced acetic acid.Keywords the electroreduction of CO2, gold palladium nanoparticle, boron doped diamond, surface modification.

Abstrak :
Elektroda Boron-Doped Diamond termodifikasi core-shell nanopartikel AuPd telah berhasil dipreparasi dengan cara perendaman BDD terminasi N dalam koloid nanopartikel AuPd. Lapisan shell Pd NP terbentuk pada core nanpartikel Au dari hasil reduksi larutan HAuCl4 dengan variasi penambahan H2PdCl4 1,0 mM dan asam askorbat. Spektrum UV-Vis dari nanopartikel Au menunjukkan panjang gelombang maksimum pada ? = 523 nm yang diikuti dengan penurunan absorbansi AuPd NP seiring pembentukan nanopartikel palladium. Karakterisasi nanopartikel menggunakan Transmission Electron Microscopy TEM menunjukkan bahwa core-shell AuPd NP memiliki bentuk flower shape dengan diameter Au NP sebesar 14,26 nm dan ketebalan Pd NP masing-masing 6,91 nm dan 4,05 nm. AuPd NP yang dideposisi ke permukaan elektroda BDD-N dikarakterisasi menggunakan Scanning Electron Microscopy Energy Dispersive X-Ray SEM-EDX dan X-Ray Photoelectron Spectroscopy XPS. Penentuan kadar oksigen dilakukan menggunakan teknik siklik voltammetri dalam larutan buffer fosfat PBS dengan variasi lamanya waktu aerasi oksigen yang diukur menggunakan DO meter. Hasil pengukuran menujukkan bahwa kemampuan pemisahan sinyal arus terhadap background pada elektroda BDDN-AuPdNP 1 S/B = 2,82 lebih baik dibandingkan BDDN-AuNP S/B = 2,59 dan BDDN-AuPdNP 2 S/B = 1,12 . Pembentukan Pd NP pada permukaan Au NP mempengaruhi sensitifitas pada elektroda sehingga modifikasi elektroda BDD-N dengan nanopartikel AuPd diharapkan dapat menghasilkan elektroda yang lebih sensitif untuk pengukuran oksigen dan dapat dikembangkan selanjutnya untuk penentuan BOD dalam air. ......Core shell nanoparticle Au Pd modified Boron Doped Diamond electrode has been succesfully prepared by immersion of BDD terminating N in Au Pd colloid nanoparticles. The Pd shell layer was formed on Au nanoparticle cores from the reduction of HAuCl4 solution with variations of 1.0 mM H2PdCl4 volume addition and ascorbic acid. UV Vis spectra of Au nanoparticles showed the maximum wavelength was obtained at 523 nm which followed by the decreasing of absorbance of AuPdNP as the formation of Pd shell. Characterization of nanoparticles using Transmission Electron Microscopy TEM shows that the AuPd Np core shell has a flower like shape with 14.26 nm of AuNP core diameter and PdNP shell thickness of 6.91 nm and 4.05 nm, respectively. The AuPd NPs were deposited on BDD N surface and were characterized using Scanning Electron Microscopy Energy Dispersive X Ray SEM EDX and X Ray Photoelectron Spectroscopy XPS. Determination of oxygen level was carried out using cyclic voltammetry in phosphate buffer solution PBS at various oxygen aeration time where its concentration was measured using DO meter. The results show that BDDN AuPdNP 1 had a better current to background signaling capability S B 2.82 than BDDN AuNP S B 2.59 and BDDN AuPdNP 2 S B 1.12 . It is belived that the formation of Pd shell on the surface of Au NP affects the sensitivity of the electrode. As the result, modification of BDD N electrodes with Au Pd nanoparticles are expected to produce more sensitive electrodes for oxygen measurements which can be further developed for Determination of BOD in the water.