A Solid Electrolyte for Sulfur Dioxide Detection - ACS Symposium Series

7 A Solid Electrolyte for Sulfur Dioxide Detection Sodium Sulfate Mixed with Rare Earth Sulfates and Silicon Dioxide Nobuhito Imanaka, Gin-ya Adachi, and Jiro Shiokawa

Downloaded by UNIV OF LIVERPOOL on November 28, 2015 | http://pubs.acs.org Publication Date: May 29, 1986 | doi: 10.1021/bk-1986-0309.ch007

Department of Applied Chemistry, Faculty of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 565, Japan

A new solid state chemical sensor for sulfur dioxide utilizing a sodium sulfate/rare earth sulfates/silicon dioxide electrolyte has been developed. The addition of rare earth sulfates and silicon dioxide to the sodium sulfate electrolyte was found to enhance the durability and electrical conductivity of the electrolyte. The electrolyte exhibits a Nernstian response in the range of SO gas concentrations from 30 ppm to 1 %. 2

As i s well-known, s u l f u r o x i d e s and n i t r o g e n o x i d e s exhausted i n t o a i r , which can r e s u l t i n a c i d r a i n , have caused s e r i o u s d e t e r i o r a t i o n of t h e environment. The p o t e n t i a l need f o r r e g u l a t i o n o f S 0 and N 0 gases i n combustion e m i s s i o n s i s , nowadays, becoming an i m p o r t a n t research area. For p r a c t i c a l measurements, s e v e r a l t e c h n i q u e s f o r analysis have been w i d e l y adopted as f o l l o w s : (1) The e l e c t r i c a l c o n d u c t i v i t y measurement o f an absorbed s o l u t i o n (2) I n f r a r e d a b s o r b t i o n a n a l y s i s (3) U l t r a - v i o l e t spectrum p h o t o m e t r i c a n a l y s i s (4) Flame photometry (5) S t a t i o n a r y p o t e n t i a l e l e c t r o l y s i s However, t h e apparatus f o r these methods i s e x p e n s i v e and comp l i c a t e d . R e c e n t l y , a c o n c e n t r a t i o n c e l l method u s i n g a s o l i d e l e c t r o l y t e has become o f i n t e r e s t f o r gas d e t e c t i o n . A p o t e n t i a l advantage o f t h i s t e c h n i q u e i s t h a t m o n i t e r i n g f o r can be undertaken s i m p l y , s e l e c t i v e l y , and c o n t i n u o u s l y w i t h low c o s t . As t h e e l e c t r o l y t e s , a l k a l i metal s u l f a t e s ( M = L i , Na, and K ) ( l - l l ) , 3-Alumina(12), and NASIC0N(13, 14) have been examined. A l k a l i m e t a l s u l f a t e s a r e c a t i o n c o n d u c t o r s a t e l e v a t e d temperature(>700 C ) . Howe v e r , they have s e v e r a l d i s a d v a n t a g e s . One i s t h e phase t r a n s f o r m a t i o n o f t h e s u l f a t e s ( 1 5 - 1 8 ) . By t h i s t r a n s f o r m a t i o n , c r a c k s occur i n the e l e c t r o l y t e body and r e s u l t i n t h e permeation o f t h e ambient gases. The o t h e r d i s a d v a n t a g e i s t h e i r low e l e c t r i c a l c o n d u c t i v i t y . Mono, d i , o r t r i - v a l e n t c a t i o n s ( 1 9 - 2 4 ) have been doped so as t o e n hance t h e i r c o n d u c t i v i t y . Furthermore, they become d u c t i l e a t a temx

0097-6156/ 86/ 0309-0121 $06.00/0 © 1986 American Chemical Society

In Fundamentals and Applications of Chemical Sensors; Schuetzle, D., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1986.

x


122

FUNDAMENTALS AND APPLICATIONS OF CHEMICAL SENSORS

p e r a t u r e h i g h e r than a p p r o x i m a t e l y 800°C. (3-Alumina i s one o f t h e other r e p r e s e n t a t i v e c a t i o n conductors. NASICON i s one o f t h e most w i d e l y used m a t e r i a l s ( 2 5 - 3 2 ) t h a t have been u t i l i z e d a s c a t i o n c o n d u c t o r s . However, both o f them a r e n o t c o m m e r c i a l l y a v a i l a b l e a t present. I n a d d i t i o n , 3-Alumina and NASICON m a t e r i a l s a r e c o n s i d e r a b l y more expensive than a l k a l i metal s u l f a t e s . I n our i n v e s t i g a t i o n , sodium s u l f a t e was s e l e c t e d a s t h e e l e c t r o l y t e . Rare e a r t h s u l f a t e s Ln^CSO.)^(Ln=Y and Gd) were added i n o r d e r t o i n c r e a s e t h e e l e c t r i c a l c o n d u c t i v i t y . S i l i c o n d i o x i d e was added so a s t o o b t a i n t h e network s t r u c t u r e which i s e f f e c t i v e f o r Na c a t i o n c o n d u c t i o n and t o prevent t h e e l e c t r o l y t e from becoming too s o f t . A t h i n n e r e l e c t r o l y t e was p o s s i b l e t o prepare by mixi n g i n SiO^. The s u p p r e s s i o n o f t h e phase t r a n s f o r m a t i o n ( 1 5 , 16) from Na2S0,-I(a h i g h temperature phase) t o Na2S0^-III(a low temperat u r e phase; was a l s o a c h i e v e d by m i x i n g r a r e e a r t h s u l f a t e s ( L n = Y and Gd) and s i l i c o n d i o x i d e i n t o sodium s u l f a t e . The a p p l i c a t i o n o f t h e N a ^ O ^ - I ^ C S O , ) ~ S i 0 ( L n = Y and Gd) e l e c t r o l y t e samples as t h e s o l i d e l e c t r o l y t e f o r an SO2 gas d e t e c t o r was i n v e s t i g a t e d . The EMF measurements were conducted by both t h e SO2 gas c o n c e n t r a t i o n c e l l ( 3 3 ) and t h e s o l i d r e f e r e n c e e l e c t r o d e ( 3 4 ) methods. S e v e r a l e f f o r t s have been c o n c e n t r a t e d on t h e development of t h e a p p r o p r i a t e r e f e r e n c e e l e c t r o d e . I n our s t u d y , t h e s u l f a t e o x i d e s o l i d r e f e r e n c e e l e c t r o d e method was adopted. 3

2

Experimental M a t e r i a l s . Sodium s u l f a t e ( p u r i t y : 99.99 % ) , s i l i c o n d i o x i d e ( p u r i t y : 99.9 %) were bought from Wako Pure Chemical I n d u s t r i e s L t d . . Y t t r i u m ( p u r i t y : 99.9 %) and g a d l i n i u m ( p u r i t y : 99.99 %) o x i d e s were purchased from Shiga Rare M e t a l I n d u s t r i e s L t d . . Rare e a r t h s u l f a t e s ( L n = Y and Gd) were prepared by adding t h e coned, s u l f u r i c a c i d i n t o r a r e e a r t h oxides(Ln=Y and Gd). Before w e i g h i n g , sodium s u l f a t e and s i l i c o n d i o x i d e were d r i e d . Rare e a r t h s u l f a t e s were a l s o heated f o r dehydrat i o n . S i n c e Ln2(S0^)^(Ln=Y and Gd) a r e c o n s i d e r a b l y h y g r o s c o p i c , t h e a c t u a l c o n c e n t r a t i o n o f r a r e e a r t h c a t i o n i n t h e m i x t u r e was d e t e r mined by t h e EDTA t i t r a t i o n . Preheated m a t e r i a l s were c o o l e d i n a d e s i c c a t o r , weighed, and mixed t h o r o u g h l y i n an agate mortar. The m i x t u r e was melted a t 1473°K f o r 1 h and then quenched. The r e s u l t i n g m a t e r i a l g w a s reground, made i n t o p e l l e t s under h y d r o s t a t i c p r e s s u r e (2.65x10 P a ) , and then s i n t e r e d a t 1073°K f o r 1 h i n a i r . P l a t i n u m s p u t t e r i n g on t h e c e n t e r s u r f a c e o f t h e e l e c t r o l y t e was conducted u s i n g a Shimadzu's i o n c o a t e r IC-50. Measurements. X-ray and thermal a n a l y s e s were c a r r i e d out f o r t h e Na2S0^-Si02 and t h e Na2S0,-Ln2(S0^)^-Si02 systems so as t o i n v e s t i gate t h e i r phases w i t h a RigaRu's R o t a f l e x d i f f r a c t o m e t e r ( C u t a r g e t ) and a Rigaku's Thermoflex, r e s p e c t i v e l y . E l e c t r i c a l c o n d u c t i v i t i e s were measured by means o f t h e complex impedance method w i t h a Hewlett Packard v e c t o r impedance meter 4800A. The a p p a r a t u s f o r t h e e l e c t r i c a l c o n d u c t i v i t y measurements a r e i l l u s t r a t e d i n F i g u r e 1. The samp l e was f a s t e n e d by s p r i n g l o a d i n g t h e q u a r t z r o d .


Sulfur Dioxide Detection

7. IMANAKA ET AL.

123

R e s u l t s and D i s c u s s i o n E l e c t r i c a l c o n d u c t i v i t y , phases, and t h e r m a l p r o p e r t i e s . Na2S0^-Si02 systems: The r e s u l t s of the phases and t h e r m a l p r o p e r t i e s a r e summarized i n T a b l e I .

Table I .

The phases and t h e r m a l p r o p e r t i e s of Na SO.-SiO ?


Sample #

Na S0 (mol%;

SiO (mol%)

90 70 50

10 30 50

2

1 2 3

4

w i t h P t s p u t t e r r e d samples. These may r e s u l t from tne2permeation o f t h e amb i e n t gases i n t h e e l e c t r o l y t e because o f t h e c r a c k s produced from the HI t o I phase t r a n s f o r m a t i o n . =


n

N a S 0 - Y ( S 0 ) - S i 0 systems(Pt s p u t t e r i n g ) : The r e s u l t s o f t h e EMF measurements as a f u n c t i o n o f S 0 gas c o n c e n t r a t i o n i s presented i n F i g u r e 9. The samples w i t h 5 min P t s p u t t e r i n g and 10 min s p u t t e r i n g on t h e working e l e c t r o d e s i d e , were prepared i n a d d i t i o n t o t h e samp l e w i t h o u t s p u t t e r i n g . The measured EMF f o r t h e N a ^ O ^ - Y ^ S O ^ ) ^ S i 0 w i t h o u t s p u t t e r i n g was i n good accordance w i t h t h e c a l c u l a t e d v a l u e i n the log(pgQ ) ^ range from -3.0 t o -2.0. Compared w i t h the c a l c u l a t e d EMF, £he measured EMF suddenly d e c r e a s e s a t an SO. c o n c e n t r a t i o n lower than 1000 ppm. F i v e min s p u t t e r i n g o f P t onto t h e e l e c t r o l y t e e n a b l e s i t t o d e t e c t t h e SO. gas w i t h good r e sponse from 500 p p m ( l o g ( p ) =-3- ) 10000 ppm(l % ) . S p u t t e r i n g of P t onto the e l e c t r o l y t e £or 10 min lowered t h e S 0 gas d e t e c t i o n l i m i t t o 200 ppm(log(pgQ )- =-3.7). As t h e p l a t i n u m s p u t t e r i n g time was i n c r e a s e d , t h e measu2ecl EMF approaches c l o s e r t o t h e c a l c u l a t e d v a l u e . The f o r m a t i o n and t h e decomposition o f t h e sodium s u l f a t e on the e l e c t r o l y t e s u r f a c e come t o occur e a s i l y by t h e i n c r e a s e o f P t s p u t t e r i n g t i m e . The e x p e r i m e n t a l r e s u l t s from s p u t t e r i n g P t f o r 10, 20, and 30 min on t h e working e l e c t r o d e s u r f a c e a r e e x h i b i t e d i n F i g u r e 10. These i s no s i g n i f i c a n t d i f f e r e n c e s i n t h e EMF response from these t h r e e samples. Only a t 30 ppm(log(pgQ )^ =-4.52), does t h e e l e c t r o l y t e w i t h 10 min P t s p u t t e r i n g shows t h e n e a r e s t EMF v a l u e t o t h a t expected. The dependence o f t h e P t s p u t t e r i n g time on t h e measured E M F / c a l c u l a t e d EMF r a t i o i s shown i n F i g u r e 11. The measured E M F / c a l c u l a t e d EMF p r o p o r t i o n changes s i g n i f i c a n t l y from 0-10 min. L i t t l e change o c c u r r e d f o r s p u t t e r i n g times g r e a t e r than 10 min. The optimum p l a t i n u m s p u t t e r i n g time i s determined t o be 10 min. Because t h e 10 min i s good enough t o s p u t t e r , both s u r f a c e s of t h e e l e c t r o l y t e has been s p u t t e r r e d f o r 10 min. The r e s u l t s f o r N a S 0 - Y ( S 0 ) . - S i 0 s o l i d e l e c t r o l y t e w i t h s p u t t e r i n g on both s u r f a c e s i s presented i n F i g u r e 12 t o g e t h e r w i t h the r e s u l t o f Na^O^. The EMF c h a r a c t e r i s t i c s f o r Na S0, remarkably d e c r e a s e s as a r e s u l t o f t h e p e n e t r a t i o n through the cleavage a p p e a r i n g i n t h e e l e c t r o l y t e , a t an S 0 gas c o n c e n t r a t i o n l e s s than 0.1 %. On t h e o t h e r hand, t h e measured EMF f o r t h e N a . S 0 - Y ( S 0 ) - S i 0 show e x c e l l e n t agreement w i t h t h e c a l c u l a t e d EMF i n t h e range o f S 0 c o n c e n t r a t i o n 30 ppm t o 1 %. In t h e l a b o r a t o r y , t h e SO. gas c o n c e n t r a t i o n c e l l method u s i n g the s o l i d e l e c t r o l y t e i s c o n s i d e r e d t o be a good t e c h n i q u e f o r d e t e c t i n g t h e SO. gas. However, i n a p r a c t i c a l u t i l i z a t i o n , t h e method i s 2

4

2

4

3

2

2

2

3

S Q

t

0

in

2

n

n

n

2

4

2

4

2

2

2

4

2

4

3

2

2



130


Figure 8

Figure 9

F i g u r e 8. The v a r i a t i o n o f the EMF f o r Na^SO^ s o l i d e l e c t r o l y t e w i t h t h e S 0 gas c o n c e n t r a t i o n 0 N a S 0 (without Pt sputtering) ( ) • Na S0^ (10 min P t s p u t t e r i n g on w o r k i n g electrode surface only)( ) • N a S 0 (10 min P t s p u t t e r i n g on both surf aces) ( ) and are c a l c u l a t e d EMFQJ, r e s p e c t i v e l y . 2

2

4

2

2

4

F i g u r e 9. The v a r i a t i o n o f the EMF f o r N a S 0 , - Y ( S 0 ) - S i 0 (48.1:11.8:40.1) s o l i d e l e c t r o l y t e w i t h the SO. gas c o n c e n t r a t i o n (Pt s p u t t e r i n g on w o r k i n g e l e c t r o d e s u r f a c e o n l y ) A Na.SO,-Y (SO,).-SiO ( 0 min)( ) • Na S0,-Y (S0,)^-Si0 , , . w x 2 4 2 4'3 2 ( 5 min)( ) # N a S 0 - Y ( S 0 , ) - S i 0 (10 m i n ) ( ) , , ana a r e c a l c u l a t e d EMF(_1), respectively. 2

9

9

2

4

3

9

V

2

4

2

3

2


2


131


7. IMANAKAETAL.

log ( P s o 2 ) h

F i g u r e 10. The v a r i a t i o n o f t h e EMF f o r t h e N a S 0 - Y ( S 0 ) -SiO. (48.1:11.8:40.1) s o l i d e l e c t r o l y t e w i t h t h e S 0 gas c o n c e n t r a t i o n ' ( P t s p u t t e r i n g on w o r k i n g e l e c t r o d e s u r f a c e o n l y ) * N a S 0 - Y (SO.).-SiO (10 min) • N a S 0 7 - Y ( S 0 ? ) ^ - S i 0 (20 min) A N a S 0 ? - Y ( S 0 7 ) ^ - S i 0 (30 min) i s c a l c u l a t e d EMFQJ. 2

A

2

4

3

2

?

A

9

9

9

9

9

9

F i g u r e 11. The P t s p u t t e r i n g time dependences o f measured E M F / c a l c u l a t e d EMF w i t h v a r i o u s t e s t S 0 gas c o n c e n t r a t i o n % 30 ppm • 100 ppm A 500 ppm 2


132


not s u i t a b l e , p a r t i c u l a r l y because the a p p a r a t u s i s expensive and complicated. The s o l i d r e f e r e n c e e l e c t r o d e method was examined i n o r d e r t o approach a more p r a c t i c a l a p p l i c a t i o n . The a p p a r a t u s f o r the s o l i d r e f e r e n c e e l e c t r o d e method i s dep i c t e d i n F i g u r e 13. The s o l i d e l e c t r o l y t e was d i r e c t l y kept i n cont a c t w i t h the s o l i d r e f e r e n c e e l e c t r o d e by f i x i n g the r e f e r e n c e p l a t i num e l e c t r o d e between them. The sample i s covered w i t h a bonding agent(SUMICERAM from Sumitomo Chemical I n d u s t r i e s L t d . ) . As the s o l i d r e f e r e n c e e l e c t r o d e , the e q u i m o l a r m i x t u r e o f n i c k e l s u l f a t e and n i c k e l o x i d e was a p p l i e d . F i g u r e 14 p r e s e n t s the EMF r e s u l t s o f t h e N a S 0 - Y ( S 0 ) - S i 0 s o l i d e l e c t r o l y t e w i t h the s o l i d r e f e r e n c e e l e c t r o d e method. I n the case o f the sample w i t h o u t P t s p u t t e r i n g , t h e measured EMF was almost the same a s the c a l c u l a t e d EMF from 100 ppm (log(p ) =-4.0) t o 1 %. The EMF a t 30 p p m ( l o g ( p ) =-4.52) was a p p r o x i m a t e l y 30 mV s m a l l e r than the c a l c u l a t e d EMF. 2Wften the p l a t i num was s p u t t e r r e d on both s u r f a c e s o f the e l e c t r o l y t e , the EMF c h a r a c t e r i s t i c s c o i n c i d e d very w e l l w i t h the c a l c u l a t e d v a l u e f o r the measured S 0 gas c o n t e n t i n the range from 30 ppm t o 1 %. The s o l i d r e f e r e n c e e l e c t r o d e technique i s a b l e t o o b t a i n almost the same r e s u l t s a s the S 0 gas c o n c e n t r a t i o n c e l l method. The a p p a r a t u s can be made more compact, s i m p l e and cheaper by u s i n g the s o l i d reference electrode technique. The S 0 gas d e t e c t i o n w i t h s o l i d r e f e r e n c e e l e c t r o d e method i s a p r o m i s i n g t e c h n i q u e f o r p r a c t i c a l applications. 2

4

2

4


S Q

3

2

±

s o

9

2

2

0

1

1

-40

1

1

—

-30

-20

F i g u r e 12. The v a r i a t i o n o f the EMF f o r N a S 0 and N a S 0 Y . ( S 0 ) . - S i 0 s o l i d e l e c t r o l y t e s w i t h the S 0 gas c o n c e n t r a t i o n (Pt s p u t t e r i n g on both s u r f a c e s f o r 10 min) 9

4

2

4

2

2

Y

S 0

• f2^4- 2^ 4)3• Na S0 i s c a l c u l a t e d EMF(l). 9

S i 0

2

A


4

IMANAKA ET AL.



quartz tube

glass packing Pt net

quartz rod bonding agent Ptfet

pWshSo'^trolyte

F i g u r e 13. The a p p a r a t u s f o r t h e EMF measurements (A s o l i d r e f e r e n c e e l e c t r o d e method)

F i g u r e 14. The v a r i a t i o n o f t h e EMF f o r N a S 0 , - Y ^ S O ^ - S i O , (48.1:11.8:40.1) s o l i d e l e c t r o l y t e w i t h t h e s o l i d r e f e r e n c e electrode(NiS0 +Ni0) % 10 min P t s p u t t e r i n g on both s u r f a c e s • without Pt s p u t t e r i n g i s c a l c u l a t e d EMF(7). 2

4


134


In conclusion, the sodium sulfate mixed with rare earth sulfates (Ln=Y and Gd) and silicon dioxide exhibits high electrical conductivity and is more durable than the pure sodium sulfate. Furthermore, the Na.SO,-Y.(SO,^-SiO. solid electrolyte maintains a similar phase to Na.SO^-I, which is excellent in Na cation conduction. The measured EMF was in excellent accordance with the calculated EMF, at S02 gas concentration in the range of 30 ppm to 1 %. In fact, the solid reference electrode method could be applicable as a practical SO2 gas detector.


Acknowledgments The present work was partially supported by a Grant-in-Aid for Developmental Scientific Research NO.57850250 from the Ministry of Education, Science and Culture. Literature Cited 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21.

Jacob, K. T.; Rao, D. B. J. Electrochem. Soc., 1979, 126, 1842-7. Worrell, W. L. Proc. the International Meeting on Chemical Sensors, Fukuoka, 1983, p. 332. Worrell, W. L.; Liu, Q. G. J. Electroanal. Chem. Interfacial Electrochem., 1984, 168, 355-62. Gauthier, M.; Chamberland, A. J. Electrochem. Soc., 1977, 124, 1579-83. Gauthier, M.; Chamberland, A.; Bélanger, A.; Poirier, M. J. Electrochem Soc., 1977, 124, 1584-7. Gauthier, M.; Bellemare, R.; Bélanger, A. J. Electrochem. Soc., 1981, 128, 371-8. Gauthier, M.; Bale, C. W. Metall. Trans. B, 1983, 14B, 117-24. Imanaka, N.; Adachi, G.; Shiokawa, J. Chem. Lett., 1983, 287-8. Imanaka, N.; Adachi, G.; Shiokawa, J. Denki Kagaku, 1983, 51, 93-4. Imanaka, N.; Adachi, G.; Shiokawa, J. Bull. Chem. Soc. Jpn., 1984, 57, 687-91. Imanaka, N.; Adachi, G.; Shiokawa, J. Proc. the International Meeting on Chemical Sensors, Fukuoka, 1983, p. 348. Itoh, M.; Sugimoto, E.; Kozuka, Z. Trans. Jpn. Inst. Met., 1984, 25, 504-10. Saito, Y.; Maruyama, T.; Matsumoto, Y.; Yano, Y. Proc. the International Meeting on Chemical Sensors, Fukuoka, 1983, p. 326. Saito, Y.; Maruyama, T.; Sasaki, S. Report of the Research Laboratory of Engineering Materials, Tokyo Institute of Technology, 1984, 9, 17-26. Kreidl, E. L.; Simon, I. Nature, 1958, 181, 1529. Saito, Y.; Kobayashi, K.; Maruyama, T. Solid State Ionics, 1981, 3/4, 393-6. El-Kabbany, F. A. I. Phys. Stat. Sol., (a), 1980, 58, 373-8. Kvist, A.; Lundén, A. Z. Naturforschg., 1965, 20a, 235-8. Höfer, H. H.; Eysel, W.; Alpen, U. v. J. Solid State Chem., 1981, 36, 365-70. Höfer, H. H.; Eysel, W.; Alpen, U. v. Mater. Res. Bull., 1978, 13, 265-70. Murray, R. M.; Secco, E. A. Can. J. Chem., 1978, 56, 2616-9.



7. IMANAKA ET AL.


135

22. Keester, K. L.; Eysel, W.; Hahn, Th. Acta Crystallogr., Sect. A, 1975, 31, S79. 23. Höfer, H. H.; Alpen, U. v.; Eysel, W. Acta Crystallogr., Sect. A, 1978, 34, S358. 24. Imanaka, N.; Adachi, G.; Shiokawa, J. Can. J. Chem., 1983, 61, 1557-61. 25. Hong, H. Y-P. Mater. Res. Bull., 1976, 11, 173-82. 26. Goodenough,J. B.; Hong, H. Y-P.; Kafalas, J. A. Mater. Res. Bull, 1976, 11, 203-20. 27. Alpen, U. v.; Bell, M. F.; Wichelhaus, W. Mater. Res. Bull., 1979, 14, 1317-22. 28. Boilot, J. P.; Salanié, J. P.; Desplanches, G.; Potier, D. Le Mater. Res. Bull., 1979, 14, 1469-77. 29. Cordon, R. S.; Miller, G. R.; McEntire, B. J.; Beck, E. D.; Rasmussen, J. R. Solid State Ionics, 1981, 3/4, 243-8. 30. Takahashi, T.; Kuwabara, K.; Shibata, M. Solid State Ionics, 1980, 1, 163-75. 31. Bogusz, W.; Krok, F.; Jakubowski, W. Solid State Ionics, 1981, 2, 171-4. 32. Alpen, U. v.; Bell, M. F.; Hofer, H. H. Solid State Ionics, 1981, 3/4, 215-8. 33. Imanaka, N.; Yamaguchi, Y.; Adachi, G.; Shiokawa, J. Bull. Chem. Soc. Jpn., 1985, 58, 5-8. 34. Imanaka, N.; Yamaguchi, Y.; Adachi, G.; Shiokawa, J. Proc. the 1984 International Chemical Congress of Pacific Basin Societies, Honolulu, Hawaii, 1984, 03C14. RECEIVED February 3, 1986


A Solid Electrolyte for Sulfur Dioxide Detection - ACS Symposium Series

Recommend Documents