Sains Malaysiana 43(11)(2014): 1769–1774

Elektrolit Dwi Lapisan Sm_0.2Ce_0.8O_1.90 (SDC)/ Y_0.25Bi_0.75O_1.5 (YSB)

untuk Sel Fuel Oksida Pepejal Bersuhu Sederhana

(Sm_0.2Ce_0.8O_1.90 (SDC)/ Y_0.25Bi_0.75O_1.5 (YSB) Bilayered Electrolytes

for Intermediate Solid Oxide Fuel Cells)

DEDIKARNI PANUH, ANDANASTUTI MUCHTAR*, NORHAMIDI MUHAMAD, EDY HERIANTO MAJLAN & WAN RAMLI WAN DAUD

Institut Sel Fuel, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor,Malaysia

Diserahkan: 22 November 2012/Diterima: 21 Julai 2014

ABSTRAK

Elektrolit dwi lapisan samarium terdop seria (SDC)/ytria terstabil bismut (YSB) dikaji adalah untuk menghasilkan sel fuel oksida pepejal bersuhu sederhana (IT-SOFC). Matlamat penyelidikan ialah mengkaji kesan suhu pengkalsinan terhadap penghasilan struktur elektrolit dwi lapisan SDC/YSB untuk IT-SOFC. Elektrolit dwi lapisan SDC dan YSB dihasilkan melalui kaedah sol-gel dan kaedah tindak balas keadaan pepejal. Serbuk SDC dikalsin pada suhu 800, 1000 dan 1200°C selama 5 jam dan serbuk YSB dikalsin pada suhu 550, 650 dan 750°C selama 2 jam. Analisis pembelauan sinar-X (XRD) mendapati serbuk SDC yang dihasilkan pada suhu 800-1200°C selama 5 jam mempunyai struktur Sm_0.2Ce_0.8O_1.90, manakala YSB mempunyai struktur Y0.25Bi0.75O1.5 pada suhu 750°C selama 2 jam. Peningkatan suhu pengkalsinan SDC pada suhu 800, 1000 dan 1200°C selama 5 jam menunjukkan peningkatan pada saiz hablur iaitu 42.4, 58.7 dan 79.9 nm. Peningkatan suhu pengkalsinan YSB sehingga suhu 750°C menyebabkan berlakunya perubahan struktur YSB daripada bentuk tetragon menjadi kiub fluorit dengan saiz hablur 28.86 nm. Hasil perbandingan ujian prestasi sel pada suhu pengoperasian sederhana (650°C), penggunaan elektrolit dwi lapisan (SDC/YSB) dengan suhu pengkalsinan SDC-1200°C dan YSB-750°C menghasilkan prestasi sel paling tinggi dengan ketumpatan kuasa 81.55 mW/cm² dan ketumpatan arus 225.36 mA/cm₂.

Kata kunci: Elektrolit dwi lapisan; komposit; pengkalsinan; sol-gel

ABSTRACT

Bilayered electrolytes samarium doped ceria (SDC)/yttria stabilised bismuth (YSB) were investigated to develop intermediate temperature of solid oxide fuel cells (IT-SOFCs). The aim of this study was to investigate the effects of the calcination on the microstructure of SDC/YSB bilayered electrolytes in IT-SOFC. Bilayered electrolytes SDC and YSB were syntesised via sol-gel and a solid state reaction method. The SDC powders were calcined at 800, 1000 and 1200°C for 5 h whereas YSB powders were calcined at 550, 650 and 750°C for 2 h. The result from XRD showed that the SDC powder having a Sm_0.2Ce_0.8O_1.9 structure after the calcine at a temperature of 800 to 1200°C for 5 h and YSB having an Y_0.25Bi_0.75O_1.5 structure at 750°C for 2 h. An increase in the calcination temperature on the SDC at 800, 1000 and 1200°C for 5 h caused an increased in crystalline size to 42.4, 58.7 and 79.9 nm, respectively. An increase in YSB calcination temperature to 750°C resulted in the transformation of YSB from tetragonal into cubic fluorite structure with a crystallite size of 28.86 nm. By comparing the results of cell performance test in intermediate operation temperature (650°C), bilayered electrolytes (SDC/YSB) with the calcination temperature SDC-1200°C and YSB-750°C showed the highest cell performance with power density 81.55 mW /cm² and current density of 225.36 mA/cm₂.

Keywords: Bilayered electrolytes; calcination; composite; sol-gel

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*Pengarang untuk surat-menyurat; email: muchtar@eng.ukm.my