本研究是以自行組裝之EAVD鍍膜系統，鍍製俱多孔性之燃料電池陰極材料LSCF, 並改變鍍膜之參數，探討鍍膜參數與所得膜質之間的關系。具多孔性之薄膜被鍍製成功並在750℃，2 小時之鍛燒溫度下得到pseudo-cubic相之鈣鈦礦結構。
鍍膜參數如鍍製溫度、鍍膜時間、先驅物溶液之流率、所加之電壓、基材之選用等參數在鍍膜時加以調變，其效果被加以討論，經過鍍製而成之膜質，在經鍛燒後，以XRD和EDS加以鑑定成分組成及結晶態，並以SEM加以觀察表面及截面膜質相應於鍍製參數之變化情形。
在下噴鍍製系統之系列中鍍製之溫度及鍍膜時間為對膜質影響最大之鍍膜參數，隨著鍍膜溫度及鍍製時間之增加，可得孔隙度高之膜質，降低鍍製溫鍍及時間，則容易得到緻密膜質，其餘鍍製參數之影響則較為不明顯，但對膜質亦有相當程度之影響。在適當的鍍製條件下，如花菜般的多孔膜被鍍製成功。
而在下噴鍍製系統之系列中，網狀的多孔膜在使用高沸點溶劑、鍍膜溫度275℃~320℃間、流率1~1.5 ml/hr、鍍膜時間2 小時內的條件下被鍍製成功，而在流率系列中，網狀結構的孔似乎隨著流率的增加而變大，在時間系列中像鐘乳狀之多孔結構在長的鍍製時間下被得到。這些俱有高度孔隙之結構，非常適合被使用於需要高孔隙之功能性膜，如氣體偵測氣，燃料電池之電極等。

In this study, a deposition system called EAVD was made to deposite porous LSCF films used as cathode material in the solid oxide fuel cell (SOFC). The relation of deposition parameters to morphology was discussed. Porous La0.8Sr0.2Co0.2Fe0.8O3 films were successfully deposited on Corning glass and ceria substrates, and a pseudo-cubic perovskite phase was obtained after a post-calcination at 750℃ for 2 hrs.
Deposition parameters, such as deposition time, deposition temperature, flow rate, voltage applied, different kinds of set-ups (downward spraying or upward spraying), were discussed. The obtained calcined films were characterized by X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX). On the other hand, surface and cross-section morphology were examined using SEM.
In the series using downward spraying system, deposition temperature and deposition time showed profound effect on morphology. With increasing the extent of these two factors, porous films were obtained. With decreasing the extent of these two factors, however, dense films were obtained. The effects of other parameters to morphology were less obvious. Under proper conditions, cauliflower-like films with high porosity were obtained.
In the series using upward spraying system (vertical set-up), reticular films were successfully obtained using deposition temperature ranging from 275~320℃, flow rate 1.0~1.5 ml/hr, and deposition time within 2 hrs. In the series of flow rate, the pores of reticular structure seemed to grow up with increasing flow rate. Under the condition of prolonged deposition (4 hrs), a stalactitc structure with micropores on it was obtained. The highly porous structures obtained in this study are very suitable for applications in gas sensor and electrodes in SOFC.

TABLE OF CONTENTS
LIST OF FIGURES AND TABLES……………………………………………………Ⅳ
CHAPTER 1 INTRODUCTION…………………………………………………..…1
CHAPTER 2 LITERATURE SURVEY………………………………..…………….4
2.1 The structure and properties of LSCF....……………………….…………………..4
2.2 A-site-deficient La0.6Sr0.4Co0.2Fe0.8O3-δ -based perovskite……….………………...8
2.3 The EAVD technique…………………………………………………………….. 10
2.4 Theoretical calculation of EAVD………………………………………………….13
2.5 Factors affecting the formation of jet...……………………………………………21
2.6 Phenomena of disruption and preferential landing……………………………......24
2.7 Morphology obtained by EAVD…………………………………………………..26
2.7.1 Four different types of morphology……………………………………….…26
2.7.2 An unique porous structure obtained only by EAVD………………………...27
2.7.3 The model proposed for unique porous structure…………………………....28
CHAPTER 3 EXPERIMENTAL PROCEDURES………………………...……….30
3.1 Chemical reagents used……………………………………………………………31
3.2 Substrate preparation………………………………………………………….…..32
3.3 Precursor solution preparation…………………………………………………….33
3.3.1 For low boiling point solvent ethanol + D.I. water……..…..……………….33
3.3.2 For high boiling point solvent butyl carbitol + ethanol……..…………..…..34
3.4 EAVD set-up………………………………………………………………………35
3.5 Analysis equipment………………………………………………………………..37
CHAPTER 4 EXPERIMENTAL RESULTS………….…………………………….40
4.1 TGA analysis………………………………………………………………………40
4.1.1 Precursor solution for low boiling point solvent (ethanol + D.I. water)..…...40
4.1.2 Precursor solution for high boling point solvent (butyl carbitol + ethanol)...41
4.2 T series: Effect of deposition temperature………………………………………...42
4.2.0 Deposition conditions…………….…………………………………………42
4.2.1 X-ray identification of each sample…………………………………………42
4.2.2 SEM morphology observation of T series…………………………………..44
4.3 H series: Effect of deposition time……………………………………………...…51
4.3.0 Deposition condition………………………………………………………...51
4.3.1 X-ray identification of each sample…………………………………………51
4.3.2 SEM morphology observation of H series…………………………………..52
4.4 F series: Effect of flow rate………………………………………………………..57
4.4.0 Deposition condition………………………………………………………...57
4.4.1 X-ray identification of each sample…………………………………………57
4.4.2 SEM surface observation of series F………………………………………..58
4.5 C series: Effect of concentration……………………………………………….….62
4.5.0 Deposition condition………………………………………………………...62
4.5.1 X-ray identification of each sample of C series……………………………..62
4.5.2 SEM surface observation of C series………………………………………..63
4.6 V series: Effect of electric field………………………………………………...…66
4.6.0 Deposition conditions...….………………………………………………...66
4.6.1 X-ray identification of each sample of V series……………………………..66
4.6.2 SEM morphology observation of V series…………………………………..67
4.7 Cross section observation of H and F series………………………………………68
4.8 A series: Effect of deposition temperature using upward spraying system……….74
4.8.0 Deposition conditions……………………………………………………….74
4.8.1 SEM morphology observation of A series…………………………………..75
4.9 B series: Effect of deposition time using upward spraying system……………….84
4.9.0 Deposition conditions……………………………………………………….84
4.9.1 Film thickness ………………………………………………………………84
4.9.2 SEM morphology observation of B series…………………………………..85
4.10 D series: Effect of flow rate using upward spraying system…………………….89
4.10.0 Deposition conditions……………………………………………………...89
4.10.1 Film thickness……………………………………………………………...89
4.10.2 SEM morphology observation of D series…………………………………90
4.11 E series: Porosity observation through profile and cross section………………..95
4.12 EDS and Xray-diffraction characterization……………………………………...99
CHAPTER 5 DISCUSSION………………………………..………………………100
CHAPTER 6 CONCLUSION.……………………………..……………………….117

Reference………………………………………………………………………………124



















LIST OF FIGURES AND TABLES
Fig.1 Principle of operation of SOFC…………….………………………………………3
Fig.2.1.1 An ideal cubic perovskite structure…………………….……………..4
Fig.2.1.2 Electrical conductivity of La0.8Sr0.2Co1-yFeyO3 as a function of temperature
in air……..…………………………………………………………………………….7
Fig.2.1.3 Electrical conductivity of La1-xSrxCo0.2Fe0.8O3 as a function of
Temperature in air..…………………………………………………...……………….7
Fig. 2.2.1 Electrical conductivity (1) and TEC values (2) at 700℃ for
(a) La0.6-zSr0.4Co0.2Fe0.8O3-δ, (b) La0.6Sr0.4-zCo0.2Fe0.8O3-δ,
(c) (La0.6Sr0.4)1-zCo0.2Fe0.8O3-δ as a function of A-site deficiency (z)…..……………..9
Fig.2.3.1 A schematic diagram of the EAVD set-up (vertical type)……………………..10
Fig.2.3.2 Processes involved in EAVD…………………………………………………..12
Fig.2.4.1 schematically diagram of cone-jet mode………………………………………14
Fig.2.4.2 A high resolution phto of single-cone jet………………………........................20
Fig.2.5.1 CCD images showing the influence of flow rate on the formation of jet:
(a) 0.3 ; (b) 0.6 ; (c) 1.0 ; (d) 2.0 ml/hr………………………………………………21
Fig.2.5.2 CCD images showing the influence of applied potential on the
formation of jet :(a) 3.5 ; (b) 4.5 ; (c) 5.6 ; (d) 8 kV……………………………..….22
Fig2.5.3 Cone-jet domains of the EAVD using the nozzles shown above………………23
Fig.2.6.1 Illustration of droplet disruption………………………………………………24
Fig.2.6.2 Illustration of preferential landing…………………………………………….25
Fig.2.7.1.1 Four types of morphology obtained using EAVD…………………………26
Fig.2.7.2 A photograph of unique porous structure……………………………………27
Fig.2.7.3 A scheme of formation mechanism of unique porous structure……………..29
Fig.3.1 Flow chart of the experiment…………………………………………………….30
Fig. 3.4.1 Schematic illustration of the downward spraying set-up of EAVD……..........35
Fig. 3.4.2 Schematic illustration of the upward spraying set-up (vertical set-up)
of EAVD……………………………………………………......................................36
Fig. 3.5.1 Schematic illustration of cross section sample preparation……………….…..38
Fig.4.1.1 TGA analysis of precursor of La0.8Sr0.2Co0.2Fe0.8O3 using 80% ethanol and
20% water as solvent………………………………………………………………...40
Fig.4.1.2 TGA analysis of precursor of La0.8Sr0.2Co0.2Fe0.8O3 using 66.66% butyl
carbitol and 33.34% ethanol as solvent…………………………..………………….41
Fig.4.2.1.1 Phase identification of films after calcinations at 750℃ for 2 hrs………..42
Fig.4.2.1.2 Phase identification of LSCF films deposited at 350℃ on glass substrate:
(a) as-deposited, (b) after calcinations……………………………………………….43
Fig.4.2.2.1 SEM images of calcined T1 sample (a) low mag.; (b) high mag……………44
Fig.4.2.2.2 SEM images of calcined T2 sample (a) low mag.; (b) high mag…………...45
Fig.4.2.2.3 SEM images of calcined T3 sample (a) low mag.; (b) high mag…………...46
Fig.4.2.2.4 SEM images of calcined T4 sample (a) low mag.; (b) high mag……………47
Fig.4.2.2.5 SEM images of calcined T5 sample (a) low mag.; (b) high mag……………48
Fig.4.2.2.6 SEM images of calcined T6 sample (a) low mag.; (b) high mag……………49
Fig.4.2.2.7 Relation between thickness and depositioin temperature……………………50
Fig.4.3.1 Phase identification of films after calcinations at 750℃ for 2 hrs…………….51
Fig.4.3.2.1 SEM images of calcined H1 sample (a) low mag.; (b) high mag…………...52
Fig. 4.3.2.2 SEM images of calcined H2 sample (a) low mag.; (b) high mag…………..53
Fig. 4.3.2.3 SEM images of calcined H3 sample (a) low mag.; (b) high mag…………..54
Fig. 4.3.2.4 SEM images of calcined H4 sample (a) low mag.; (b) high mag…………..55
Fig. 4.3.2.5 SEM images of calcined H5 sample (a) low mag.; (b) high mag…………..56
Fig.4.4.1.1 Phase identification of films after calcinations at 750℃ for 2 hrs…………..57
Fig. 4.4.2.1 SEM images of calcined F1 sample (a) low mag.; (b) high mag…………...58
Fig. 4.4.2.2 SEM images of calcined F2 sample (a) low mag.; (b) high mag…………...59
Fig. 4.4.2.3 SEM images of calcined F3 sample (a) low mag.; (b) high mag………..….60
Fig. 4.4.2.4 SEM images of calcined F4 sample (a) low mag.; (b) high mag…………...61
Fig.4.5.1 Phase identification of films after calcinations at 750℃ for 2 hrs…………….62
Fig. 4.5.2.1 SEM images of calcined C1 sample (a) low mag.; (b) high mag…………...63
Fig. 4.5.2.2 SEM images of calcined C2 sample (a) low mag.; (b) high mag…………...64
Fig. 4.5.2.3 SEM images of calcined C3 sample (a) low mag.; (b) high mag…………...65
Fig.4.6.1 Phase identification of films after calcinations at 750℃ for 2 hrs…………….66
Fig. 4.6.2.1 SEM image of calcined V1 sample…………………………………………67
Fig. 4.6.2.2 SEM image of calcined V2 sample…………………………………………67
Fig.4.7.1 Cross section of H1 with thickness about 3.53 μm………………………….68
Fig.4.7.2 Cross section of H2 with thickness about 6.1 μm…………………………...68
Fig.4.7.3 Cross section of H3 with thickness about 10.1 μm………………………….69
Fig.4.7.4 Cross section of H4 with thickness about 23.8 μm………………………….69
Fig.4.7.5 Cross section of H5 with thickness about 27.1 μm………………………….70
Fig.4.7.6 Relation between film thickness and deposition time…………………………70
Fig.4.7.7 Cross section of F1 with thickness about 6.73 μm…………………………..71
Fig.4.7.8 Cross section of F2 with thickness about 11.12 μm…………………………...71
Fig.4.7.9 Cross section of F3 with thickness about 15.2 μm…………………………….72
Fig.4.7.10 Cross section of F4 with thickness about 14.87 μm………………………….72
Fig.4.7.11 Relation between film thickness and flow rate……………………………….73
Fig.4.8.1.1 SEM images of as-deposited A1 sample (a) low mag. ; (b) high mag………75
Fig.4.8.1.2 SEM images of as-deposited A2 sample (a) low mag. ; (b) high mag………76
Fig.4.8.1.3 SEM images of as-deposited A3 sample (a) low mag. ; (b) high mag………77
Fig.4.8.1.4 SEM images of as-deposited A4 sample (a) low mag. ; (b) high mag………78
Fig.4.8.1.5 SEM images of as-deposited A5 sample (a) low mag. ; (b) high mag………79
Fig.4.8.1.6 SEM images of as-deposited A6 sample (a) low mag. ; (b) high mag………80
Fig.4.8.1.7 SEM images of as-deposited A7 sample (a) low mag. ; (b) high mag………81
Fig.4.8.1.8 SEM images of as-deposited A8 sample (a) low mag. ; (b) high mag………82
Fig.4.8.1.9 SEM images of as-deposited A9 sample (a) low mag. ; (b) high mag………83
Fig.4.9.1 Relation between thickness and flow rate……………………………………..84
Fig.4.9.2.1 SEM images of calcined B1 sample (a) low mag. ; (b) high mag…………..85
Fig.4.9.2.2 SEM images of calcined B2 sample (a) low mag. ; (b) high mag…………..86
Fig.4.9.2.3 SEM images of calcined B3 sample (a) low mag. ; (b) high mag…………..87
Fig.4.9.2.4 SEM images of calcined B4 sample (a) low mag. ; (b) high mag…………..88
Fig.4.10.1 Relation between thickness and flow rate……………………………………89
Fig.4.10.2.1 SEM images of calcined D1 sample (a) low mag. ; (b) high mag…………90
Fig.4.10.2.2 SEM images of calcined D2 sample (a) low mag. ; (b) high mag…………91
Fig.4.10.2.3 SEM images of calcined D3 sample (a) low mag. ; (b) high mag…………92
Fig.4.10.2.4 SEM images of calcined D4 sample (a) low mag. ; (b) high mag…………93
Fig.4.10.2.5 SEM image of as-deposited D4 sample at low mag………...……………..94
Fig.4.11.1 SEM images of a hole from sample D2 for the observation of the film profile (a) 500X……………………………………………………………….......................95
Fig.4.11.1 SEM images of a hole from sample D2 for the observation of the film profile
(b) 1000X…………………………………………………………………………….96
Fig.4.11.1 SEM images of a hole from sample D2 for the observation of the film profile
(c) 1500X…………………………………………………………………………….96
Fig.4.11.1 SEM images of a hole from sample D2 for the observation of the film profile (d) 3000X……………………………………………………………………….……97
Fig.4.11.2 SEM images of cross section of sample B4 Fig.4.11.2 (a) 1000X……….…..97
Fig.4.11.2 SEM images of cross section of sample B4 Fig.4.11.2 (b) 1500X…………...98
Fig.4.11.2 SEM images of cross section of sample B4 Fig.4.11.2 (c) 2500X…………...98
Fig.4.12.1 for low solvent precursor solution……………………………………………99
Fig.4.12.2 XRD pattern of a LSCF film deposited on ceria substrate……………….......99

Table.2.1 XRD and TEC data of La1-xSrxCo0.2Fe0.8O3 and
La0.8Sr0.2Co1-y FeyO3 ………………………………………………….………6
Table 3.1.1……………………………………………………………………………….31

1 A. J. Appleby, A.C. Lloyd, and C. K. Dyer, The future of fuel cell, in Scientific American, July (1999)56-75.
2 W. Smith, J. Power Sources, 86(1-2) (2000)74-83
3 T. Kurihara, H. Mori, H. Ohmura, K. Ikeda, K. Tomida, in: Proceedings of the fifth FCDIC fuel cell sysmposium, Tokyo, Japan, 1996, P.217
4 Osamu Yamamoto, Electrochimica Acta 45 (2000) 2423-2435
5 L. G. Coccia, G. C. Tyrrell, J. A. Kilner, D. Waller, R. J. Chater, I. W. Boyd, Appl. Surf. Sci. 96-98 (1996) 795.
6 K. Hayashi, O. Yamamoto, Y. Nishigaki, H. Minoura, Solid State Ionics 98(1997)49
7 G. L. Bertrand, G. Caboche, L.-C. Dufour, Solid State Ionics 129 (2000) 219
8 H. B. Wang, J. F. Gao, D. K. Peng, G. Y. Meng, Mater. Chem. Phys. 72 (2001) 297
9 K. L. Choy, S. Charojrochkul, B. C. H. Steele, Solid State Ionics 96 (1997) 49
10 A.A. van Zomeren, ElM. Kelder, J.C.M. Marijnissen, J. Schoonman, J. Aerosol Sci. 25 (1994) 1229
11 S.C. Singhal, Solid Oxide Fuel Cell (The Electrochem. Soc., Pennington, NJ, 1989)
12 L.-W. Tai, M.M. Nasrallah, H.U. Anderson, D.M. Sparlin, S.R. Sehlin, Solid State Ionics 76 (1995) 259.
13 L.-W. Tai, M.M. Nasrallah, H.U. Anderson, D.M. Sparlin, S.R. Sehlin, Solid State Ionics 76 (1995) 273
14 B. C. H. Steele, Solid State Ionics , 86:88 (1996) 1223
15 L. Kindermann, D. Dos, H. Nickel, K. ilpert, C. C. Appel, F. W. Poulsan, J. Electrochem. Soc., 144 (1997)717.
16 K. Zheng, B. C. H. Steele, M. Sahibzada and I. S. Metcalfe, Solid State Ionics, 86-88(1996)1241-1244.

17 R.S. Roth, J. Res. Nat. Bur. Stand. 58 (1957) 75.
18 B.C.H. Steele, Solid State Ionics 75 (1995) 157.
19 G. Ch. Kostogloudis, Ch. Ftikos, Solid State Ionics 126 (1999) 143-151
20 C. H. Cnen, M. H. J. Emond, E. M. Kelder, B. Meester and J. Schoonman, J. Aerosol Science, 30(7) (1999) 959-967.
21 Soo Gil Kim, Jin Yong Kim, Hyeong Joon Kim, Thin Solid Films 376(2000) 110-114
22 S. Charojrochkul, K. L. Choy and B. C. H. Steele, Solid State Ionics, 121(1999)107-113.
23 W. Bai, K. L. Choy, R. A. Rudkin and B. C. H. Steele, Solid State Ionics, 113-115(1998)259-263.
24 K. Choy, W. Bai. S. Charojrochkul, B.C. H. Steele, J. Power Sources, 71(1998)361-369.
25 K. L. Choy and W. Bai, Thin Solid Films, 372(2000)6-9.
26 K. L. Choy and B. Su, Thin Solid Films, 388(2001)9-14.
27 B. Su and K. L. Choy, Thin Solid Films, 359(2000)160-164.
28 C. H. Chen, E. M. Kelder, P. J. J. M. van der Put and J. Schoonman, J. Mater. Chem., 6(5) (1996)765-771.
29 C. H. Chen, A. A. J. Buysman, E. M. Kelder and J. Schoonman, Solid State Ionics, 80(1995)1-4.
30 C. H. Chen, E. M. Kelder, J. Schoonman, J. Mater. Sci. 31 (1996) 5437-5442
31 Izumi Taniguchi, Robert C. van Landschool, Joop Schoonman, Solid State Ionics 156 (2003) 1-13
32 Izumi Taniguchi, Robert C. van Landschool, Joop Schoonman, Solid State Ionics 160 (2003) 271-279
33 T. Nguyen and E. Djurado, Solid State Ionics, 138 (2001)191-197.
34 A. G. Bailey, Electrostatic spraying of liquids, John Wiley & Sons, New York, 1988.
35 G. I. Taylor, Proc. R. Soc. London, A, 1964, 280, 383.
36 A.M. Gannan-Calvo, J. Aerosol Sci., 1994, 25,suppl. 1, s309.
37 W.C. Hinds, Aerosol technology, John Wiley and Sons, New York, 1982.
38 L. Rayleigh, Philos. Mag. 14 (1882) 184
39 L. Rayleigh, Proc. London Math. Soc., 10(1878) 4.
40 J. Zeleny, Phys. Rev. 10(1917)
41 B. Vonnegut, R.L. Neubaruer, J. Colloid Sci. 7 (1952) 616.
42 A.M. Gana-Calvo, J. Davila, A. Barrero, J. Aerosol Sci. 28 (1997) 249.
43 A. Neukermans, J. Appl. Phys. 44(1973) 4769
44 A.G. Bailey, W. Balachandran, J. Electrostatics 10 (1981) 99.
45 M. Cloupeau, B. Prunet-Foch, J. Electrostatics 22 (1989) 135.
46 W. Balachandran, P. Miao, P. Xiao J. Electrostatics 50 (2001) 249-2
47 許慶雄, 碩士論文: 以超音波霧化製程製備之SnO2薄膜性質, 國立中山大學材料科學研究所 (2001).