Departemen Fisika, Fakultas Sains dan Analitika Data (FSAD), Institut Teknologi Sepuluh Nopember (ITS) akan menyelenggarakan kembali kegiatan Seminar Seninan pada minggu ke-4 perkuliahan Semester Gasal 2023/2024 ini, tepatnya pada tanggal 18 September 2023.
Pada Seminar Seninan yang ke-2 ini, Guru Besar dari Laboratorium Material Maju, Departemen Fisika FSAD ITS, Prof. Dr. Suasmoro, DEA., yang akan menjadi narasumber.
Topik yang akan diangkat dalam kesempatan kali ini adalah “LOCAL STRUCTURE DISTORTION EVALUATION OF Ba0.5Sr0.5Fe1-xCuxZr0.05O3-δ FACING PHYSICAL PROPERTIES ALTERATION”.
Kegiatan ini akan dilaksanakan secara luring pada pukul 13.30 s.d. 15.00 WIB, bertempat di Teater B ITS. Mahasiswa di lingkungan Departemen Fisika wajib menghadiri kegiatan ini dan mengisi lembar kehadiran secara daring dengan cara memindai QR Code yang tersedia di depan pintu masuk Teater B ITS.
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Abstract:
The composition Ba0.5Sr0.5Fe1-xCuxZr0.05O3-δ (BSFCZ, x=0-0.15) was successfully synthesized by the sol-gel self-combustion method using starting materials of the associated metals and citric acid as fuel combustion. Their structure, local structure, electric, and magnetic properties are investigated. The XRD measurements revealed that all the oxides exhibit a cubic structure, with space group Pm3m and lattice parameter increases with x, a = 3.9230 Å for x=0 up to a = 3.9474 Å for x = 0.15. The X-ray absorption data are discussed in detail concerning Fe, and Cu K-edge shift was related to Fe and Cu’s oxidation state (OS).
The OS of Fe was 3.49 for the BSFZ sample and became 3.6 and 3.4 for x=0.05 and x=0.15, respectively; correspondently, the OS of Cu was 2.12 and 2.28. The local lattice distortion was evaluated through EXAFS data. The Fourier transforms simulation of scattering contributions from the first neighbor oxygen shell was used to assess the Fe-O and Cu-O bond length. The substitution of iron by copper and zirconium leads to a corresponding increase of the iron valence state and, thus, the formation of the Jahn-Teller effect Fe4+ ion.
The nonstoichiometric δ-value (3-δ) measured by iodometric titration is consistent with X-ray absorption data leading to oxygen vacancy defect. The electrical conductivity increases significantly after substituting Fe and Zr with Cu up to 60 Scm-1, a potential used as a SOFC cathode. Furthermore, the magnetic properties show that the magnetic saturation increase significantly for x>0.
Departemen Fisika, Fakultas Sains dan Analitika Data (FSAD), Institut Teknologi Sepuluh Nopember (ITS) akan menyelenggarakan kembali kegiatan Seminar Seninan