Effect of Variation Substitution of Nd and Eu on the Crystal Structure of Y-124 Superconductor (Y1-x-yNdxEuyBa2Cu4O8??)

Laura Laudensia Senly Jalut,Wayan Gede Suharta,Windaryoto Windaryoto

doi:10.24843/bf.2022.v23.i02.p06

Abstract

In this study, the substitution of elements Nd and Eu on the superconductor Y1-x-yNdxEuyBa2Cu4O8?? (Y-124) has been carried out using compounds Y2O3, BaCO3, CuO, Nd2O3 and Eu2O3 with molar variations of Nd (x) and Eu (y), respectively. 0, 0,05, 0,1, 0,15 and 0,2 respectively to determine the effect of Nd and Eu substitution on the volume fraction and crystal structure of the superconducting Y-124. Samples were synthesized using wet mixing method with HNO3 as solvent, followed by calcination process at 600 oC for 3 hours and sintering process at 900 oC for 10 hours. Analysis of the structure of the superconducting Y-124 was carried out by characterizing X-ray Diffraction (XRD) and Fourier-Transform Infrared Spectroscopy (FTIR). The results of XRD characterization showed a fine and sharp spectrum which indicated that crystallization had occurred completely. The resulting spectrum was dominated by the Y-124 phase and a small percentage of the impurities were detected. Substitution of Nd and Eu elements resulted in volume fractions of 82,7 %, 83,6 %, 84,4 %, 87,0 % and 85,9 %, respectively. The volume fraction value increased with the addition of Nd and Eu from 0 to 0,15, then decreased at 0,2. This indicates that the optimization of the addition of Nd and Eu is at a value of 0,15 in the molar ratio of compounds. The substitution of Nd and Eu elements also causes changes in the lattice parameters towards the a-axis with values between 3,7549 and 3,8323 , towards the b-axis with values between 3,8094 and 3,8425 , and towards the c-axis with values between 26,7390 and 26,8970. The FTIR results show the presence of an absorption band in the YBCO region, but the sample still contains impurities which are indicated to come from BaCO3 and HNO3.

Highlights

0,2 respectively to determine the effect of Nd
sharp spectrum which indicated that crystallization had occurred
The resulting spectrum was dominated by the Y-124 phase

Summary

Hasil karakterisasi X-Ray diffraction (XRD)

Pola difraksi hasil karakterisasi XRD sampel superkonduktor Y1-x-yNdxEuyBa2Cu4O8-δ dengan variasi penambahan Nd dan Eu (0, 0,05, 0,1, 0,15, dan 0,2) diperlihatkan pada Gambar 1. Berdasarkan hasil identifikasi menggunakan program Match 3 maka dilakukan perhitungan fraksi volume yang bertujuan untuk mengetahui persentase kemunculan fase Y1-x-yNdxEuyBa2Cu4O8-δ dalam sampel. Untuk melihat pola perubahan fraksi volume fase Y-124 dengan penambahan unsur Nd dan Eu, maka hasil perhitungan fraksi volume digambarkan dalam sebuah kurva yang diperlihatkan pada Gambar 2. Berdasarkan hasil perhitungan fraksi volume yang diperlihatkan pada Tabel 1 dan Gambar 2 terlihat bahwa penambahan unsur Nd dan Eu (0, 0,05, 0,1, dan 0,15 molar) pada superkonduktor fase Y-124 mengakibatkan nilai fraksi volume bertambah besar (82,7%, 83,6%, 84,4% dan 87,0%). Hasil refinement juga menghasilkan nilai Indeks Miller dari spektrum yang terbentuk, dengan memanfaatkan hubungan hukum Bragg dan jarak antar bidang pada struktur kristal orthorombik yang diperlihatkan pada persamaan (2) dan (3) [18].

Hasil Karakterisasi Fourier Transform Infrared Spectroscopy (FTIR)

Kesimpulan