신소재공학과

Seminar

Date 20180725 

■ Title             : Dynamic Control and in-situ Measurements of Oxygen Nonstoichiometry and Phase of Layered Cuprate-based Thin Films by Electrochemical Pumping

 

■ Speaker         :  Dr. Chang Sub Kim 


■ Date and Time
 :  7/25 (Wed) 1:30 PM 

 

■ Venue           :  Applied Engineering Buliding (W1-1) Seminar Room #2

 

■ H o s t           :  Prof. Woo Chul Jung

 

■ Abstract :    

Three major criteria are essential for a good solid oxide fuel cell (SOFC) electrode: 1) mixed ionic and electronic conductivity, 2) electrocatalytic activity towards oxygen surface exchange reaction, and 3) chemical and chemo-mechanical stability. Conventional method of assessing these electro-chemo-mechanical properties requires doping different concentrations of aliovalent cations and/or controlling atmosphere. These, however, are constrained by solubility limits of dopants, the range of oxygen partial pressures readily experimentally achievable, and require knowledge of the applicable defect chemical model. In this study, we control and measure oxygen defect types, concentrations, and phases in promising rare earth cuprate (RE2CuO4: RE = rare earth) SOFC cathode materials by electrochemical pumping of oxygen through an yttria-stabilized zirconia supporting electrolyte. These layered perovskites can incorporate both oxygen interstitials and vacancies, as well as two different crystal structures – T and T’ – depending on the Cu-O coordination, thereby broadening the range of investigations. Oxygen nonstoichiometry values and crystal structures are determined by in-situ measurement of chemical capacitance and x-ray diffraction, respectively, and are correlated with surface kinetics, in-plane conductivities, ionic diffusivities, and chemo-mechanical properties.

No. Subject Author Date Views
» 7/25 (Wed) Dr. Chang Sub Kim (Department of MSE, MIT) ADMINI 2018.07.24 217
Notice 7/13 (Fri) Prof. Dong Ryeol Whang (Johannes Kepler University Linz, Austria) ADMINI 2018.07.09 219
Notice 6/5 (Tue) Prof. Sunghwan Lee (Baylor University) ADMINI 2018.06.05 428
263 5/29 (Tue) Prof. Sang Ho Oh (Yonsei Univ. College of Medicine) ADMINI 2018.05.29 431
262 5/15 (Tue) Prof. Myung Gil Kim (Dept. of Chemistry, Chung-Ang Univ.) ADMINI 2018.05.15 642
261 5/8 (Tue) Prof. Ju-Young Kim (UNIST MSE) ADMINI 2018.05.09 578
260 5/1 (Tue) Prof. Duk-Yong Yoon (KAIST MSE) ADMINI 2018.04.30 705
259 4/24 (Tue) Kyeong Ho Chang (CEO, Innox Advanced Materials) ADMINI 2018.04.23 609
258 4/10 (Tue) Prof. Ki Jun, Yu (Yonsei Univ., School of Electrical and Electronic Engineering) ADMINI 2018.04.09 700
257 4/3 (Tue) Master Byung-Gi Choi (Samsung Advanced Institute of Technology) ADMINI 2018.04.02 572
256 3/27 (Tue) Prof. Seungbum Hong (KAIST MSE) ADMINI 2018.03.26 543
255 3/20 (Tue) Prof. Jung In-Ho (Seoul National University, MSE) ADMINI 2018.03.20 416
254 3/13 (Tue) Prof. Jong-Beom Baek (School of Energy and Chemical Engineering, UNIST) ADMINI 2018.03.13 413
253 3/6 (Tue) Prof. Seok-Young Ryu (KAIST CS) ADMINI 2018.03.05 372
252 2/27 (Tue) Dr. Jin-Woo Han (NASA) ADMINI 2018.02.27 438
251 2/20 (Tue) Dr. Jae Beom Jang (Sungkyunkwan Univ) ADMINI 2018.02.19 408
250 2/8 (Thu) Prof. Pei-Chen Su (Nanyang Technological University) file ADMINI 2018.02.05 395
249 2/13 (Tue) Prof. Sungkyu Kim (Northwestern Univ) ADMINI 2018.01.31 478
248 1/9 (Tue) Dr. Choon Won Byeon, ETRI ADMINI 2018.01.09 495
247 12/23 (Sat) Prof. Liangbing (Bing) Hu/Univ. of Maryland file ADMINI 2017.12.22 515