The Refinemet of Framework Structures of Natural Mordenite and Clinoptilolite Crystals Using Rietveld Method

Framework structures of clinoptilolite and mordenite phases in natural zeolit from Bayah have been succesfully analysed using Rietveld Method. The diffraction intensity data were collected using X-Ray Difractometer (XRD) at P3IB-BATAN. The refinement of the clinoptilolite and mordenite phases have been carried out and the results show that there are poly cation K-Mg clinoptilolite phase, with space group symmetry of C2/m No.12, monoclinic crystal system and poly cation Ca-Na mordenite phase, with space group symmetry of Cmcm No.63, orthorombic crystal system. Chemical formulas of clinoptilolite and mordenite phases are (K5,17 Mg0,16) (Al6Si30O72). 24H2O and [(Na 5,63 Ca 1,13) (Al8Si40O96). 22H2O per unit cell respectively. Fitting quality (goodness-of-fit) gave a value of Rwp = 10,34%

Characterization Of Natural Zeolite By X-ray Diffractometer

An identification of framework mineral structure of natural zeolit Bayah, Lampung and Malang was carried out by Reitveld methods. X ray diffraction intensity of Natural zeolit was measured by an X-Ray Diffractometer (XRD). The refinement of Clinoptilolite and Mordenite phases have been carried out and the results of refinement show that in Bayah and Lampung were Clinoptilolite phase ( space group C2/m No.12, Bravais lattice is Base-Centered and crystal system is monoclinic) and lattice parameter are a = 17,69(2) Å, b = 17,92(1) Å dan c = 7,422(9) Å respectively (Bayah zeolite) and a = 17,69(2) Å, b = 17,92(1) Å dan c = 7,422(9) Å respectively (Lampung zeolite) and pore size are S10R = 10,685 Å dan S8R = 8,193 Å. While Malang zeolites phase (space group Cmcm No.63, Bravais lattice is Base Centered and crystal system is orthorombic) was Mordenite phase and the lattice parameter are a = 18,115(8) Å, b = 20,520(9) Å dan c = 7,515(2) Å. The pore size are S8R = 11,43 Å dan S12R = 7,730 Å. Material of natural zeolit from Bayah and Lampung have Cation Exchange Capasity (CEC) bigger than Malang (acording to results of the framework structure analysis)

Analisis Struktur Kristal Napo3 pada Superionik Komposit (Agi)0,5 (Napo3)0,5 dengan Metode Rietveld

ANALISIS STRUKTUR KRISTAL NaPO3 PADA SUPERIONIK KOMPOSIT (AgI)0,5 (NaPO3)0,5 DENGAN METODE RIETVELD. Telah berhasil disintesis bahan baru superionik komposit (AgI)0,5 (NaPO3)0,5, melalui metode pendinginan cepat. Pengukuran struktur kristal dilakukan menggunakan Difraktometer Sinar-X di Departemen Fisika Universitas Ibaraki, Jepang. Profil pola difraksi Sinar-x bahan baru tersebut memperlihatkan beberapa puncak Bragg menunjukkan kesesuaian dengan kristal presipitat (NaPO3 )n dan kristal -AgI. Analisis struktur kristal dengan metode Rietveld pada fasa natrium meta-fosfat (NaPO3 )n dan fasa -AgI, telah dilakukan. Hasil refinement masing-masing fasa menunjukkan bahwa struktur kristal presipitat tersebut teridentifikasi dari campuran fasa natrium meta-fosfat (NaPO3)n, simetri grup ruang I41/a No.88, tetragonal, parameter kisi a = b = 13,32(3)Å dan c = 6,22(3) Å dan fasa γ-AgI simetri grup ruang F-43m No 216, FCC dengan parameter kisi a = 6,49(3). Tiga puncak kuat pada refleksi hk0 dengan intensitas tinggi berasal dari presipitat (NaPO3)n terletak pada sudut 2θ = 19,144o bidang (220), 2θ = 26,009o, bidang (400) dan 2θ = 30,45o bidang (420). Hasil difraksi ini menunjukkan bahwa presipitat tersebut, benar-benar presipitat dari kristal NaPO3 bukan amorf. Sedangkan puncak lainnya merupakan puncak fasa γ-AgI pada sudut 2 = 39,183o bidang (220) yang berimpit dengan puncak presipitat (NaPO3)n, pada sudut 2 = 38,783o bidang (251). Satu puncak tunggal dengan intensitas tinggi, terletak pada sudut 2θ = 23,690o bidang (111) adalah milik fasa γ-AgI. Beberapa puncak Bragg yang muncul teridentifikasi berasal dari struktur kristal presipitat NaPO3 dan fasa γ-AgI

Pressure Dependence of Crystal Structure and Ionic Conductivity on Composite Glass (AgI)0.7(AgPO3)0.3

The superionic composite glass, (AgI)0.7(AgPO3)0.3 has been succesfully synthesized by melt quenching method. The crystall structure of coin type composite glass at various  pressure of 100, 300 and 700 kg/cm2 have been measured by using an X-ray Difractometer at PTBIN-BATAN. The X-ray difraction pattern shows some Bragg peaks    correspond to the crystaline γ-AgI. The increasing of pressure result the peaks become broaden and shift to the lower angle. This indicates that the crystal size is decreasing and the microstrain is increasing. Three strong peaks at (111), (220) and (311) have been analyzed by using a Gaussian  Fitting. Based on  calculation, crystal size (D) of (AgI)0.7(AgPO3)0.3 at pressures of 100, 300 and 700 kg/cm2 are 1114 Å, 13165 Å and 7240 Å respectively, while  microstrain values (η)  are 4 x 10-3 (1), 7.5 x 10-3 (4) and   8 x 10-3 (4). The composite glass  (AgI)0.7(AgPO3)0.3 crystal structures at pressures of 100, 300 and 700 kg/cm2 have been analyzed by using a Rietveld method.  The refinement results show that the peaks correspond to γ-AgI phase with a symmetry space group F-4 3 m No. 216, FCC, with the lattice constant namely 6.518(3), 6.508(3) and 6.506Ǻ(2) at a pressure of  100, 300 and 700 kg/cm2 respectively.  The increasing of microstrain (η), and crystal size (D) and the decreasing of lattice constant (a) will increase the ionic mobility, thus increasing the ionic conductivity. The function of pressure on melt γ-AgI phase into glass matrix AgPO3 decreases the lattice constant and the crystal size, cause the increasing  of microstrain  broadening and ionic conductivit

Struktur Kristal dan Konduktivitas Ionik pada Komposit Superionik Agi-ag Hasil Sputtering

STRUKTUR KRISTAL DAN KONDUKTIVITAS IONIK PADA KOMPOSIT SUPERIONIK AgI-Ag HASIL SPUTTERING. Telah dilakukan pendeposisian Ag terhadap kristalin AgI agar diperoleh bahan superionik yang memiliki konduktifitas tinggi pada suhu ruang. Untuk tujuan ini, kristalin AgI telah dimodifikasi dengan cara pendeposisianAgmelalui teknik Sputtering selama 45 menit dan 60 menit. Komposit superionik baru yang dihasilkan adalah AgI-Ag. Hasil pola difraksi sinar-x pada temperatur ruangmenunjukkan terjadinya transformasi struktur sebagian dari γ-AgI (Face Center Cubic / FCC) menjadi β-AgI (Hexagonal). Hasil pendeposisian menunjukkan peningkatan konduktivitas ionik dari ~ 10-7 S/cm pada kristalin AgI menjadi ~ 10-3 S/cm pada komposit superionik AgI-Ag. Sementara itu dari hasil pengujian kekerasan dan densitas menunjukan adanya penurunan dengan lama waktu pendeposisian