Influence of layer numbers on the structural and electrical performance of cobalt-free SrFe0.5Ti0.5O3-δ cathode for ntermediate-temperature solid oxide fuel cell application

International Conference on Sustainable Energy and Green Technology 2018

能源学;生态环境科学

Baharuddin, N.A.^1 ; Wan Yusoff, W.N.A.^1 ; Muchtar, A.^1^2 ; Somalu, M.R.^1 ; Abdul Samat, A.^1^3 ; Anwar, M.^1^4

Fuel Cell Institute, Universiti Kebangsaan Malaysia, UKM, Bangi, Selangor

43600, Malaysia^1

Centre for Engineering Materials and Smart Manufacturing (MERCU), Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, UKM, Bangi, Selangor

43600, Malaysia^2

Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), Kampus UniCITI Alam, Sungai Chuchuh, Padang Besar, Perlis

02100, Malaysia^3

US-Pakistan Center for Advanced Studies in Energy (USPCAS-E), National University of Sciences and Technology, NUST, H-12, Islamabad

44000, Pakistan^4

关键词: Electrical conductivity;    Electrical performance;    Field emission scanning electron microscopy;    Intermediate temperature solid oxide fuel cell;    Operating temperature;    Samarium doped ceria electrolytes;    Screen printing technique;    Sintering temperatures;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/268/1/012132/pdf
DOI  :  10.1088/1755-1315/268/1/012132

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

The influence of layer numbers on the structural and electrical performance of SrFe0.5Ti0.5O3-δ cobalt-free cathode was studied. The SrFe0.5Ti0.5O3-δ cathode films fabricated using screen-printing technique with different layer numbers sintered at 1300 °C for 2 h were characterised using field-emission scanning electron microscopy (FESEM) for structural analysis and four-point van der Pauw method for direct current electrical conductivity (σDC). FESEM micrographs confirmed that the SrFe0.5Ti0.5O3-δ cobalt-free cathode films (fabricated with different layer numbers) adhered well on the samarium doped ceria electrolyte surface. The porous films were also uniform without crack formation. The thicknesses of the as-fabricated cathode films were 9.0 ± 0.5, 25.6 ± 1.0, 54 ± 0.6, 71.2 ± 1.4 and 92.2 ± 1.6 μm for layer numbers 1 (1×), 4, 7, 10 and 13 times (13×), respectively. The electrical performance of SrFe0.5Ti0.5O3-δ cobalt-free cathodes was reported within the operating temperature ranging from 550 °C to 800 °C as the targeted application was the intermediate temperature solid oxide fuel cell. The layer numbers (thickness) dependence of σDC suggested a mechanism of long electron pathway at the surface and through the films due to the increase in pores. While the sintering temperature is kept constant, increasing in the number of layers increased the pores accordingly. Hence, the lowest σDC value at 800 °C (2.45 S cm-1) is obtained for SrFe0.5Ti0.5O3-δ cathode films with high number of layers (13×). The highest σDC value (16.46 S cm-1) was recorded for a single layer (1×) SrFe0.5Ti0.5O3-δ cathode film. Although the conductivity value was still far from the desired theoretical conductivity of 100 S cm-1, this result was better than that of the literature that reported the same composition, thereby showing that the quality of cathode film was improved.