Of the High Performance Gallium Arsenide (GaAs) Nanowires (NWs)

8/14/2019 Of the High Performance Gallium Arsenide (GaAs) Nanowires (NWs)

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CITY UNIVERSITY OF HONG KONG

DEPARTMENT OF

PHYSICS AND MATERIALS SCIENCE

BACHELOR OF ENGINEERING (HONS) IN MATERIALS ENGINEERING 2009-2010

DISSERTATION

Synthesis n! "h#"te#i$ti%n %& nn%st#'"t'#e! sei-"%n!'"tin te#i*s &%# s%*#

"e** ++*i"ti%n

,y

L .%/ Min

M#"h 2010


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Synthesis n! "h#"te#i$ti%n %& nn%st#'"t'#e! sei-"%n!'"tin te#i*s &%# s%*#

"e** ++*i"ti%n

By

L .%/ Min

S',itte! in +#ti* &'*&i*ent %& the

#e'i#eents &%# the !e#ee %&

BACHELOR OF ENGINEERING (HONS)

IN

MATERIALS ENGINEERING

F#%

City nie#sity %& H%n %n

M#"h 2010

3#%4e"t S'+e#is%# 5 3#%&ess%# L.#en"e 6'


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Signed ___________________________

LAM KWOK MING


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Acknowledgemen

My I e7+#ess y sin"e#e #tit'!e t% y s'+e#is%#8 3#%&ess%# L.#en"e 6'8 &%#

int#%!'"in e t% the &ie*! %& s"ienti&i" #ese#"h in te#i*s s"ien"e8 his

en"%'#eent8 his %+ini%ns8 his in*',*e 'i!n"e n! "#iti"* insihts in he*+in

e t% .e** "%+*ete y &in* ye# +#%4e"t in &ie*! %& te#i*s s"ien"e

I %.e the "%+*eti%n %& y thesis t% Miss A! Che'n &%# he# #et he*+ n!

'i!n"e in the ,ehi%#* testin te"hni'es in Dye-sensiti$e! s%*# "e**8 n! ny

+ie"es %& sin"e#e !i"e

I .%'*! *i/e t% thn/ the te"hni"ins in Cent#e %& S'+e#-Di%n! n! A!n"e!

Fi*s (COSDAF) &%# thei# e7+e#tise in the intenn"e %& "%+'te#s n! %the#

*,%#t%#y e'i+ent 6ith thei# "%ntin'%'s "%n"e#n8 the e7+e#ients .e#e "%n!'"te!

s%%th*y th#%'h%'t the inestiti%n

I .ish t% "/n%.*e!e the st&& e,e#s in the De+#tent %& 3hysi"s n! Mte#i*s

S"ien"e &%# thei# s'++%#t n! *',*e !is"'ssi%n Lst ,'t n%t *est8 this thesis is

!e!i"te! t% y &i*y e,e#s .h% en*ihtene! e t% st'!y h#! n! !e%te y

ene#y t% the &ie*! %& te#i*s s"ien"e #ese#"h

i


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T!"le o# Conen$

3e N',e#

Acknowledgemen:::::::::::::::::::::::::i

T!"le o# Conen$::::::::::::::::::::::::ii

L%$ o# F%g&'e$ !nd T!"le$:::::::::::::::::::::

A"$'!c::::::::::::::::::::::::::::ii

() In'od&c%on::::::::::::::::::::::::::31

*) L%e'!&'e Re+%ew::::::::::::::::::::::::3;

21 6%#/in +#in"i+*e n! the st#'"t'#e %& DSSC:::::::::::3;

22 Dye:::::::::::::::::::::::::::3

2< Nn%"#yst**ine sei"%n!'"t%#:::::::::::::::::3?

2> E*e"t#%*yte::::::::::::::::::::::::3?

2? C%'nte# e*e"t#%!e:::::::::::::::::::::3@

2 Fi** F"t%#::::::::::::::::::::::::3@

2@ AM1>:::::::::::::::::::::::::3@

29 Re"ent #ese#"h %n Dye-sensiti$e! s%*# "e**:::::::::::3@

,) O"-ec%+e$:::::::::::::::::::::::::::39

.) E/0e'%men!l P'oced&'e$::::::::::::::::::::310


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>1 M%#+h%*%y %& =nO nn%.i#es n! TiO2"%te! =nO nn%.i#es:::319

>2 -#y Di&"ti%n n*ysis %& =nO nn%.i#es n!

TiO2"%te! =nO nn%.i#e:::::::::::::::::320

>; C'#es n*ysis %& +h%t%"'##ent e#ses %*te #+h:::::::321

>< Dye sensiti$e! s%*# "e**s +e#&%#n"e n! e&&i"ien"ies:::::::32> Sttisti"* An*ysis:::::::::::::::::::::32>

>? E&&e"ts %& s+#y see!in eth%!:::::::::::::::32

> E&&e"ts %& #%.th "y"*es %& =nO nn%.i#es:::::::::::32@

>@ E&&e"ts %& the TiO2 "%tin e&&e"ts n! "%tin eth%!:::::32@

>9 E&&e"ts %& !e+%siti%n tie TiO2%n =nO nn%.i#es:::::::::329

>10 E&&e"ts %& !e+%siti%n s #ti% %& TiO2%n =nO nn%.i#es:::::329

>11 3%ssi,*e e##%#s n! i+#%eents::::::::::::::329

2) Concl&$%on$::::::::::::::::::::::::: 3;>

3) Re#e'ence$:::::::::::::::::::::::::::3;?

4) A00end%/:::::::::::::::::::::::::::3


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Fi'#e 1 St#'"t'#e n! %+e#tin +#in"i+*e %& !ye-sensiti$e! s%*# "e**s:::::3 S"nnin E*e"t#%n Mi"#%s"%+e (SM @20)::::::::::::31;

Fi'#e ? 3*n ie. %& =nO nn%.i#es #%.th &%# ; "y"*es ::::::::31>

Fi'#e 3*n ie. %& TiO2"%te! =nO nn%.i#es #%.th &te# ; "y"*es::: 31?

Fi'#e @ TiO2"%te! %n =nO nn%.i#es (O25A#8 1518 !e+%siti%n tie >ins)::31

Fi'#e 9 TiO2"%te! %n =nO nn%.i#es (O25A#8 2518 !e+%siti%n tie 1>ins)31

Fi'#e 10 C#%ss se"ti%n* ie. %& the =nO nn%.i#es:::::::::: 31@

Fi'#e 11 C#%ss se"ti%n* ie. %& the TiO2"%te! =nO nn%.i#es ::::::319

Fi'#e 12 RD s+e"t# %& =nO nn%.i#es n! ITO s',st#te::::::::320

Fi'#e 1; RD s+e"t# %& TiO2"%te! =nO nn%.i#es n! ITO s',st#te:::321

Fi'#e 1< Ae#e 3h%t%"'##ent- %*te "'#e %n !i&&e#ent #%'+s::: 32;

Fi'#e 1> Ae#e 3h%t%"'##ent- %*te "'#e %& TiO2"%te! DSSC in s

#ti% 151 !e+%sit &%# >8 108 1> in'tes n! "%nt#%*:::::::: 328 108 1> in'tes n! "%nt#%*:::::::: 32>

Fi'#e 1 nn%.i#es 'sin s+#y see!in eth%!:::::::::::::3;1

Fi'#e 1@ =nO nn%.i#es 'sin s+#y see!in eth%! ::::::::::3;2

T,*e 1 3h%t%e*e"t#i" +#ete#s %& DSSCs::::::::::::::: 32

A"$'!c

This st'!y is t% /e 'se %& s+#y s see!in eth%! n! DC net#%n s+'tte#in

s the !e+%siti%n eth%! %& titni' %7i!e %n $in" %7i!e nn%.i#e in Dye-

i


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sensiti$e! s%*# "e** t% "hiee the '*tite %* %& +#%!'"in hih e&&i"ien"y s%*#

"e**s ,y &st n! "%st &,#i"tie eth%! Di&&e#ent s #ti%s %& %7yen t% #%n n!

the !e+%siti%n tie .e#e ni+'*te! !'#in "%tin t% %+tii$e e&&i"ien"y %& the

s%*# "e**

2@ s+*es #e ssine! in th#ee #%'+s5 "%nt#%* #%'+8 %ne-t%-%ne %7yen t% #%n

#%'+8 n! t.%-t%-%ne %7yen t% #%n #%'+ .ith #i%'s !e+%siti%n tie %& &ie

in'tes8 ten in'tes8 n! &i&teen in'tes #es+e"tie*y

The e#e e&&i"ien"y %& the DSSCs .hi"h +#%!'"e! ,y the !e+%siti%n eth%! %&

DC net#%n s+'tte#in is &%'# ties hihe# thn tht %& the "%nt#%* "e** B%th

#+hi"* n! sttisti"* #es'*ts ie sini&i"nt ei!en"es t% s'++%#t the hy+%thesis

tht the e&&i"ien"y %& the s%*# "e**s in the t.%-t%-%ne %7yen t% #%n #%'+ is

sini&i"nt*y hihe# thn tht in the %ne-t%-%ne %7yen t% #%n #%'+8 .hi"h is *s%

sini&i"nt*y hihe# thn tht in the "%nt#%* #%'+ F'#the#%#e8 the e&&i"ien"y %&

DSSCs % !e+%siti%n tie %& &i&teen in'tes is hihe# thn tht %& ten in'tes

#%'+8 .hi"h is *s% hihe# thn tht %& &ie in'tes #%'+

It is "%n"*'!e! tht the e&&i"ien"y %& DSSC .e** +e#&%#s in t.%-t%-%ne %7yen t%

#%n #%'+ .ith !e+%siti%n ties %& &i&teen in'tes .hen s+#y see!in eth%! n!

net#%n s+'tte#in !e+%siti%n eth%! #e 'se!


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() In'od&c%on

Dye-sensiti$e! s%*# "e** (DSSC) is +h%t%%*ti" "e** .hi"h ene#tes e*e"t#i"ity ,y

*iht Mi"he* G#t$e* .s the &i#st %ne .h% inente! DSSC ,y 'sin !ye-sensiti$e!

.i!e,n! + ene#y sei"%n!'"t%# s s',st#te C%+#e t% t#!iti%n* si*i"%n s%*i!

stte s%*# "e**8 DSSC hs hihe# e&&i"ien"y .ith *%.e# &,#i"ti%n "%st DSSC

'ses +h%t%sensitie !ye t% ene#te +h%t%e*e"t#%n inste! %& 'sin +-n 4'n"ti%n

!i%!es

By 'sin titni' !i%7i!e nn%+#ti"*e &i* s the n%!e %& DSSC8 the "%ne#si%n

e&&i"ien"y "n ,e i+#%e! t% 11 It is ,e"'se the titni' !i%7i!e nn%+#ti"*es

+#%i!e *#e s'#&"e #e t% s%/ '+ *%t %& !yes B't the e*e"t#%n #e"%,inti%n

#te .%'*! *iit the "e** e&&i"ien"y8 ,e"'se the t#ns+%#tin #te %& the e*e"t#%ns .i**

,e"%e s*%.e#8 *e! the e*e"t#%ns !i&&'si%n #te t% the n%!e !e"#eses

=nO hs .i!e ,n! + %& ;;e t #%% te+e#t'#e8 it *s% hs *#e e7"itti%n

,in!in ene#y .hi"h is ,%'t ?0e Besi!es8 =nO hs hih ,#e/!%.n st#enth n!

"%hesi%n st#enth .hi"h ies %%! +hysi"* ,i*ity The %,i*ity n! the e7"ti%n

st,i*ity %& =nO #e *s% e#y hih8 s% tht =nO nn%.i#es s%*# "e** hs %%! n!

st,*e +e#&%#n"e

DSSC "%nsist %& n',e# %& e#ti"* sin*e "#yst**ine et* %7i!e nn%.i#es8 .hi"h

he %%! e*e"t#i"* "%n!'"tiity A*s% it .i** +#%i!e !i#e"t +th.y t% n%!e

.hi"h hs hihe# e*e"t#%n !i&&'si%n #te thn the nn%+#ti"*e &i*8 s% the e&&i"ien"y

%& the "e** .i** *s% ,e in"#ese! =nO nn%.i#es #e n%n-t%7i" s',stn"es n! it !%es

1


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n%t !e"%+%se een +*"e in 1000%C %en It is "hei"**y st,*e te#i* n! "n

,e #e'se ny ties .ith%'t ny +hysi"* n! "hei"* "hnes M%#e%e#8 =nO

nn%.i#es #e esy t% &,#i"te8 s% ny in!'st#ies &,#i"te =nO nn%.i#es The#e

#e ny eth%!s t% &,#i"te =nO nn%.i#es8 s'"h s "hei"* +%# !e+%siti%n8

e*e"t#%"heist#y n! hy!#%the#* "heist#y The %st "%%n .y t% &,#i"te is

t% 'se .et "hei"* #%te8 ,e"'se the +#%!'"ti%n "%st is ##e*y *%. The DSSCs

e&&i"ien"y .i** he ,%'t 02 t% 1>1 ,y 'sin these eth%!s

Dint et * si! tht &te# "%te! *ye# %& .i!e ,n! + te#i* *i/e TiO 28 the

e&&i"ien"y .i** ,e in"#ese! Be"'se the "%te! .i!e ,n! + *ye# "n #e!'"e the

#e"%,inti%n #te %& e*e"t#%ns8 *s% TiO2 thin *ye# hs hih +%#%'s s'#&"e .hi"h

in"#eses the s'#&"e #e S% in the &'t'#e !ee*%+ent8 TiO2 "%te! DSSC s'#e*y hs

the *'e &%# &'#the# st'!y

2


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*) L%e'!&'e 'e+%ew

*)( 5o'k%ng 0'%nc%0le !nd 6e $'&c&'e o# DSSC

Dye-sensiti$e! s%*# "e** (DSSC) "n "hne the +h%t%n in *iht s%'#"e t% the e*e"t#i"

+%.e# The #e"ti%n t/en insi!e hs the $e#% net "hei"* "hne8 .hi"h is "y"*i"

#e"ti%n Insi!e the DSSC8 the#e #e t.% s',st#tes .hi"h #e in!i' !%+e! tin %7i!e

(ITO) n! F*'%#ine !%+e! tin %7i!e (FTO)8 n%the# "%+%nents *i/e nn%"#yst**ine

sei"%n!'"t%# %7i!e &i* !ye ( =nO nn%.i#e)8 e*e"t#%*yte8 e*e"t#%!e n! "%'nte#

e*e"t#%!e

;


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Figure 1 Structure and operating principle of dye-sensitized solar cells [1]

The +#in"i+*e %& DSSC is e7"ite! !ye %*e"'*es ,y the +h%t%n in *iht s%'#"e8 .hen

the +h%t%n hs en%'h ene#y t% %e#"%e the ene#y ,n! + %& the sei"%n!'"t%#8

it .%'*! e7"ite !ye %*e"'*es8 the e7"ite! !ye %*e"'*es then eit e*e"t#%ns n!

4'+ int% the "%n!'"ti%n ,n! %& the e*e"t#%!e E*e"t#%ns .%'*! %e t% the s',st#te

n! +ssin the *%! th#%'h the e7te#n* .i#e

*)* D7e

The #%*e %& the !ye in DSSC is +h%t% sensiti$e# The e"hnis is tht .hen the !ye

is 'n!e# *iht s%'#"e8 its %*e"'*es #e +h%t% "tite! in e7"ite! stte n! in4e"t

e*e"t#%n int% the "%n!'"ti%n ,n! %& the sei"%n!'"t%# e*e"t#%!e t hih s+ee!

A&te# tht8 the !ye .%'*! "hne ,"/ t% its %#iin* stte !'e t% *%st e*e"t#%n % the

e*e"t#%*yte ,y the e*e"ti%ns !%nti%n The e*e"t#%*yte 'se! #e 's'**y %#ni" s%*ent

%# i%ni" *i'i! s%*ent .ith I;-I-8 .hi"h #e!%7 #e"ti%n t/e +*"e J2K


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The#e #e see#* "#ite#i tht !ye #e'i#es t% &'*&i** s% tht it "%'*! &'n"ti%n .e** s

%%! !ye in DSSC8 they #e5 n intensie ,s%#+ti%n +%.e# in the isi,*e #ei%n8

st#%n !s%#+ti%n +%.e# %n the s'#&"e %& nn%"#yst**ine sei"%n!'"t%# e*e"t#%!es8

n! n e&&i"ient e*e"t#%n in4e"ti%n +%.e# in the "%n!'"ti%n ,n! %& the sei"%n!'"t%#

J;K B%th "#ite#i "n 7ii$e "%ne#si%n e&&i"ien"y %& s%*# "e**s

The#e #e t.% !yes 's'**y 'se! in in!'st#y The &i#st %ne is N19 !ye8 .ith

"hei"* &%#'*5 R'JLL(NCS)2K .he#e L 282-,y+y#i!y*-


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i+%#tnt8 it sh%.s the #ti% tht the nn%.i#e "n #%.th .ith *%n n! st#iht

nne#8 n! tht "n +#eent *#e %'nt %& nn%.i#es e#e t%ethe# J>K

3%*yi!e is %ne %& the s%*'ti%ns tht "n in"#ese the s+e"t #ti% %& nn%.i#es ,y

"%nt#%**in the nn%.i#es #%.th in the se !i#e"ti%n J?K

Figure 2 Cross-sectional view of Zn nanowires [!]

In"#ese the n',e# %& #%.th "y"*e "n *enthen the nn%.i#es A *%n nn%.i#e hs

*#e# sh%#t "i#"'it "'##ent !ensity8 *#e e&&e"tie #e t% ie %%! *iht

s"tte#in e&&e"t8 sin"e *iht "n e7"ite the !ye n! #'n the syste8 s% tht %#e !ye

"n ,e e7"ite! ,y %%! *iht s"tte#in e&&e"t8 s% tht hin hihe# e&&i"ien"y J@K B't

.hen the #%.th "y"*es #e t%% ny8 the nn%.i#e .%'*! #%.th in e#y !ense

nne# n! e#e t%ethe# The e&&i"ien"y .%'*! *%.e# ,e"'se the +h%t%ns "n %n*y

#e"h the s'#&"e +#t8 ,'t "nn%t % int% the #%%t +#t %& the nn%.i#e

The#e #e ny eth%!s t% &,#i"te nn%.i#es8 &%# e7+*e8 the#* !e"%+%siti%n8

hy!#%the#* synthesis8 s%*-e* eth%!s8 s%*i! in%#ni" +hses8 s+'tte#in8

?


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e*e"t#%"hei"*8 t%i" *ye# !e+%siti%n8 n! "hei"* %# +hysi"* +%# !e+%siti%n

S%e &,#i"ti%n eth%!s *i/e "hei"* +%# !e+%siti%n #e "%st*y .hi"h is n%t

"%%n*y 'se! J9K

*). N!noc'7$!ll%ne $em%cond&co'

Nn%"#yst**ine sei"%n!'"t%# hs .i!e ,n! +8 s% it is 's'**y 'se! in DSSC

The #e"%,inti%n %& e7"ite! e*e"t#%n y &&e"t the e&&i"ien"y %& DSSC By ien

!i#e"t +th &%# the ,s%#+ti%n %& *iht n! *#e# s'#&"e #e %& sei"%n!'"t%# &i*

&%# !ye %*e"'*es "%ne#t t% e*e"t#%ns8 the e&&i"ien"y .%'*! #et*y in"#ese B't i&

the sei"%n!'"t%# &i* is t%% thi"/ %# t%% *#e#8 it .%'*! in"#ese the #e"%,inti%n

#te n! .ste the e7"ite! e*e"t#%n =nO8 TiO28 SnO28 N,2O>8 MO #e 's'**y 'se! s

sei"%n!'"t%# %7i!es in !ye-sensiti$e! s%*# "e** J2K

*)1 Elec'ol7e

The#e #e !i&&e#ent /in!s %& e*e"t#%*ytes A%n the8 the "%%n e*e"t#%*ytes

in"*'!e *i'i! e*e"t#%*yte8 'si-s%*i! stte e*e"t#%*yte n! s%*i! e*e"t#%*yte Thei#

in &'n"ti%n is t% "%+enste the *%st %& e*e"t#%ns e7"ite! ,y the *iht s%'#"e8

's'**y ,y s%*'ti%n %& n %#ni" s%*ent %# i%ni" *i'i! s%*ent .ith I ;I #e!%7

syste It he*+s inii$in the n',e# %& h%*e &te# the in4e"ti%n %& the e*e"t#%n int%

the sei-"%n!'"t%# A*s%8 .henee# i%!i!e (I

) is #eene#te!8 the #e!'"ti%n %&

t#ii%!i!e (I;) .i** ,e "##ie! %'t t the "%'nte# e*e"t#%!e8 the .h%*e "i#"'it .i** then ,e

"%+*ete! th#%'h e7te#n* *%! Besi!es8 the !!ities s'"h s


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C%'nte# e*e"t#%!e 's'**y 'se &*'%#ine !%+e! tin %7i!e (FTO) "%te! .ith thin

+*tin' *ye# 3*tin' "n ie %%! e7"hne "'##ent !ensity &%# the #e!%7

#e"ti%n t/e +*"e In %#!e# t% &,#i"te h%%ene%'s thin *ye# %& +*tin' "%tin

%n &*'%#ine !%+e! tin %7i!e (FTO)8


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"%+#e! t% tht %& the %ne .ith%'t +#ehetin hy!#%the#* t#etent8 n! the s+e"t

#ti% n! *inent "n ,e "%nt#%**e! ,y #yin the +#ehetin tie JK

,) O"-ec%+e$

The %,4e"ties %& this #ese#"h #e &,#i"tin =nO nn%.i#es .hi"h hs TiO2"%tin8

test the e&&i"ien"y %& DSSCs t% "%+#e the +e#&%#n"e %& DSSCs .hi"h is .ith%'t

TiO2"%tin A*s% 'sin s+#y see!in eth%! t% &,#i"te DSSCs in &st n! esy

.y t% "hiee hih e&&i"ien"y DSSCs By 'sin S"nnin E*e"t#%ni" Mi"#%s"%+e

(SEM) n! -#y !i&"ti%n (RD) t% inestite the %#+h%*%y n!

"#yst**%#+hi" st#'"t'#e %& =nO nn%.i#es A*s% st'!y the #i%'s &,#i"ti%n

eth%!s %& =nO nn%.i#e .hi"h 'ses DC net#%n s+'tte#in !e+%siti%n t% "%t

TiO2 An*ysis h%. s #ti% %& %7yen t% #%n n! !e+%siti%n tie "n &&e"t the

9


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e&&i"ien"y %& DSSCs Fin**y8 this te"hni'e .i** he*+ the &'t'#e !ee*%+ent %&

DSSC

.) E/0e'%men!l P'oced&'e$

.)( S!m0le 0'e0!'!%on

In!i' tin %7i!e (ITO) .ith thi"/ness %& 0> .s "%te! %n %ne si!e s'#&"e %& the

*ss t% "t s s',st#tes It .s "'t int% si$e %& ,%'t 1 " 7 2 " ,y !i%n! +en

T% %i! "#"/s %""'#in t the see!e! si!e %& the ITO s',st#te8 the s"#t"h .s

!e t the ,"/ si!e %& the ITO s',st#te In this .y8 the !e"#ese in e&&i"ient*y %&

the DSSC !'e t% the +#esen"e %& "#"/s .%'*! ,e %i!e! As ,%th si!es #e %+ti"*

10


19/58

t#ns+#ent8 %hete# is 'se! t% i!enti&y the see!e! si!e8 ,e"'se the see!e! si!e is

e*e"t#i"* "%n!'"tie The sheet #esistn"e %& the ITO is 10 "P The s+*e .s

then +'t int% '*t# s%ni" inst#'ent t% i,#te %'t the !'st Then 'se "et%ne t% #inse

the %#ni" "%ntinnt n! !isti**e! .te# t% .sh in%#ni" "%ntinnt J12K

D'#in the .h%*e +#%"ess8 &%#"e+s sh%'*! ,e 'se! &%# hn!*in the s+*e t% %i!

"%ntinti%n n! *%es sh%'*! ,e .%#n t% +#%te"t %'# hn!s C%ntinnt y

&&e"t =nO nn%.i#es t% #%.th8 ,e"'se the si$e %& "%ntinnt is '"h *#e# then

nn% si$e S% it y #et*y &&e"t the e&&i"ien"y %& DSSC

.)* G'ow6 o# 8nO n!now%'e$

01 M see! s%*'ti%n .s +#e+#e! ,y !iss%*in $in" "ette in ethn%*8 n! then

s+#yin the see! s%*'ti%n %n t% ITO s'#&"e .hi"h .s ;0 " +#t e#ti"**y &%#

th#ee ties Anne*in t ;>0%C &%# 20 in'tes8 then the =nO see!s *ye# is &%#e!

Mi7 01M %& $in" nit#te hy!#te (=n (NO;)2?H2O) n! 01M

he7ethy*enetet#ine (HMT) s%*'ti%n .ith 151 #ti% They i7e! t%ethe# t% &%#

the #%.th s%*'ti%n .hi"h .s @0L Then +'t the ITO s',st#tes e#ti"**y .ith the

see!e! si!es &"in %'t.#! t% the *ss ,%tt*e int% the .e** i7e! #%.th s%*'ti%n

This "%'*! %i! *#e *%e#tes &%#e! %n the s'#&"e %& see!e! si!e The

s%*'ti%n .s then +'t int% n %en .ith 90QC &%# ; h%'#s t% *et the =nO nn%.i#es t%

#%.th T%t**y #%.th ; "y"*es %n e"h s+*e ,y #e+etin th%se ste+s Bet.een

e"h "y"*e8 the s+*e .s #inse ,y !isti**e! .te# n! "et%ne8 ,e"'se the#e y

++e# *#e =nO *%e#tes %n the see!e! s'#&"e8 n! nee! !isti**e! .te# n!

"et%ne t% .sh the %'t J1;K8J1


20/58

isi,*e *#e =nO *%e#tes &te# +'t in n %en &%# ; h%'#s .hi"h y tt"h %n

the ITO s',st#tes

.), DC m!gne'on $0&e'%ng de0o$%%on o# T%O*

A&te# the ITO s',st#te #%.th &%# ; "y"*es8 then 'se! !isti**e! .te# n! "et%ne t%

#inse the s+*e in DC net#%n s+'tte#in !e+%siti%n .s 'se! t% !e+%sit TiO 2

&i* %n t% the =nO nn%.i#e *ye# Rti% %& 151 n! 152 %& #%n s t% %7yen s

i7t'#es .%'*! +'+ int% the "hine8 n! !e+%sit &%# >8 10 n! 1> in'tes &%# t.%

!i&&e#ent s #ti% The "%tin %& TiO2&i* "%'*! in"#ese the e&&i"ien"y %& DSSC ,y

i+#%e! the e*e"t#i"* "%n!'"tiity

Figure " #itaniu$ target

.). D7%ng

=nO nn%.i#es &%#e! .hite thin *ye# n! TiO 2 &i* &%#e! t#ns+#ent thin

*ye# %n the .h%*e s+*e s'#&"e 6e stn!#!i$e the "tie #e s > 7 >

s'#e8 s% "'tte# .s 'se! t% s"#t"h %'t the 'n.nte! =nO nn%.i#es n! TiO2&i*

On*y .hite > 7 > s'#e =nO nn%.i#es .ith TiO 2&i* #e *e&t %n the

s+*e The !ye .s 'se! #'theni' ,se! (B'


21/58

=nO nn%.i#es he en%'h tie t% !i+8 n! it "%'*! in"#ese the ,s%#+ti%n #te ,y

in"#ese the .%#/in te+e#t'#e t% ,%'t @0%C J1?K It "n *s% ens'#e the .te# is

!#ie! .y t% %i! i+#ente! in s+*e B't t%% *%n !ye ie#si%n tie .i**

*e! =nO nn%.i#es !iss%*e int% the !ye s%*'ti%n8 n! y &&e"t the e&&i"ien"y %&

DSSC

.)1 A$$em"l%ng DSSC$

A&te# the DSSC ,s%#, the !ye8 "%n!'"tie t+e st'"/ #%'n! the "tie #e n!

then 'se +i+ette &i**e! .ith I;-I-s e*e"t#%*yte ,y "+i**#y &%#"es8 then !#%+ 2 !#%+s %&

I;-I- s e*e"t#%*yte t% the "tie #e %& ITO The "%'nte# e*e"t#%!e SnO25 F (FTO) is

s',st#te tht "%te! .ith thin +*tin' &i* %n the s'#&"e A FTO is then "%e# %n

the see!e! si!e %& the ITO n! st'"/ t%ethe# ,y "*i+s This ens'#e the + !istn"e %&

ITO n! FTO "n ,e inii$e8 s% tht the e&&i"ien"y %& DSSC .%'*! n%t ,e &&e"te!

,y the i# + in ,et.een the8 *s% %i! the !is"%nne"ti%n %& the

.)2 Sol!' $%m&l!%on e$

AM 1> is s%*# si'*ti%n test stn!#! The DSSC is +*"e! +e#+en!i"'*# t% the

S%*# Si'*t%# .hi"h ene#te! *iht intensity %& 100062.ith .e*enth5 ;@0-

90 n t% %,se#e the +h%t%"'##ent %*te "h#"te#isti"s J1K The "%+'te# se

the #e"%#!e! *'es %& "'##ent n! %*te8 the +h%t%"'##ent %*te "h#"te#isti"s

(the #e*ti%n %& +h%t%"'##ent !ensity e#se %*te) "n ,e +*%tte! %'t &%# n*ysis

.)3 S!m0le 0'e0!'!%on #o' SEM

S"nnin E*e"t#%n Mi"#%s"%+e (SEM) is n inst#'ent t% t/e the ies %& the

s'#&"e %#+h%*%y8 n! EDS is 'se! &%# ettin the "hei"* "%+%siti%n

in&%#ti%n %& te#i* It "n t/e ie !%.n t% nn% si$e8 s% tht the #%.th

1;


22/58

"%n!iti%n %& the =nO nn%.i#es n! the "%tin "%n!iti%n %& TiO 2"n ,e seen "*e#*y

.ith /n%.n !iensi%ns 'n!e# SEM A s** +#t %& the ITO s',st#te .s "'t %'t n!

"%te! .ith %*! +#ti"*es ,y s+'tte# !e+%siti%n This "%'*! in"#ese the e*e"t#i"*

"%n!'"tiity %& the s+*e8 n! he hihe# #es%*'ti%n ie 'n!e# SEM Fi'#e sh%.s s"nnin E*e"t#%n Mi"#%s"%+e

Figure % Sputter coating $ac&ine 'FC ( 11*

Figure + Scanning *lectron ,icroscope 'S, .2)

1) Re$&l$ !nd D%$c&$$%on

1)( Mo'06olog7 o# 8nO n!now%'e$ !nd T%O*co!ed 8nO n!now%'e$

The +*n ie. n! the "#%ss se"ti%n* ie. %& =nO nn%.i#es n! TiO 2"%te! =nO

nn%.i#es "n ,e %,se#e! ,y 'sin S"nnin E*e"t#%n Mi"#%s"%+e (SEM8 SM-@20)

A se#i%'s %& SEM ies .e#e t/en t% sh%. h%. =nO nn%.i#es n! TiO 2"%te!

1


23/58

=nO nn%.i#es #%.th ,y .et "hei"* #%'te Fi'#e ? is the +*n ie. %& =nO

nn%.i#es &te# ; "y"*es %& #%.th Sin"e =nO nn%.i#es he sin*e "#yst**ine

st#'"t'#e8 they he the he7%n* sh+e n! #%. in e#ti"* nne# The thi"/ness

is ,%'t 100-200n .hi"h is e#y thin8 ,e"'se =nO nn%.i#es .e#e +"/e! t%ethe#

t% #%. n! he the se*& %#ni$e ,i*ity .hen #%.in The s+"es ,et.een e"h

he7%n* =nO nn%.i#e #e n%t the se n! the#e ++e#s h%*e t the '++e#

#iht "%#ne# %& the ie8 it y !'e t% the 'neen*y !ist'#,e! see!s ,y s+#yin

eth%! Ce#tin s+"e !istn"e se+#ti%n "n in"#ese the s'#&"e #e n! it is

nee!e! &%# !ye ,s%#+ti%n Besi!es8 *iht "n % int% the #%%t %& the =nO nn%.i#es8

th's enhn"e the *iht s"tte#in e&&e"t n! in"#ese the *iht h#estin

1>


24/58

Figure / 0lan view of Zn nanowires growt& for " cycles

Fi'#e sh%.s the +*n ie. %& TiO2"%te! =nO nn%.i#es &te# ; "y"*es %& #%.th

This ie .s t/en the t *e&t e!e %& the e&&e"tie #e The .i#e thi"/ness is *s%

in the #ne %& 100-200n They *s% he he7%n* sh+es n! #%.th in e#ti"*

nne# The e!e si!e sh%.s the =nO nn%.i#es #%.th t% n%the# !i#e"ti%n8 ,e"'se

the =nO nn%.i#es t the e!e !% n%t he neih,%# t% #e*y They y #%.th in

!i&&e#ent !i#e"ti%n ,'t sti** in he7%n* sh+e This ie "nn%t see the TiO2"%tin

"*e#*y8 sin"e the *ye# thi"/ness is e#y thin !%.n t% nn% si$e Fi'#e @ sh%.s the

TiO2"%te! %n =nO nn%.i#es ,y DC net#%n s+'tte#in !e+%siti%n In %7yen t%

#%n s #ti% is 151 eni#%nent8 the !e+%siti%n t%%/ > in'tes The#e #e s%e

1?


25/58

TiO2 "%te! t the ,%tt% *e&t "%#ne#8 it .s n%t !e+%sit ** #%'n! the #e In Fi'#e

98 the TiO2 "%te! ** #%'n! the =nO nn%.i#es *i/e s+i!e#.e,8 it &%# *in/s t% e"h

=nO nn%.i#e This ie is t/en in O7yen t% A#%n s #ti% is 251 eni#%nent8

the !e+%siti%n tie is 1> in'tes

Figure ! 0lan view of #i2coated Zn nanowires growt& after " cycles

1


26/58

Figure . #i2coated on Zn nanowires 23r4 114 deposition ti$e +$ins)

1@


27/58

Figure 5 #i2coated on Zn nanowires 23r4 214 deposition ti$e 1+$ins)

Fi'#e 10 is the "#%ss se"ti%n* ie. %& the =nO nn%.i#es8 they #e ,%'t 2>

*%n Fi'#e 11 is the "#%ss se"ti%n* ie. %& the TiO 2"%te! =nO nn%.i#es They

#e ,%'t 2? *%n The TiO2"%tin "nn%t ,e %,se#e! een the !e+%siti%n tie

is '+ t% 1> in'tes *%n sin"e the thi"/ness %& the TiO2"%tin *ye# is in nn% si$e

A*th%'h Fi'#e 10 n! 11 he sii*# *enth8 the !i&&e#en"e ,et.een t.% ies is

the s'#&"e %n t%+ %& the =nO nn%.i#es Fi'#e 10 hs #%'h s'#&"e .hi*e Fi'#e

11 hs s%%the# s'#&"e8 .hi"h ens the *enths %& =nO nn%.i#es !i&&e#en"es #e

s**e#8 *s% the TiO2"%tin y &i** int% h%*es

The #ti% %& *enth t% !iete# is "**e! s+e"t #ti% The s+e"t #ti% %& the =nO

nn%.i#es .s ,%'t 19 n! tht %& TiO2"%te! =nO nn%.i#es .s ,%'t 20 Hihe#

s+e"t #ti% ens hin *%ne# nn%.i#e *enth .ith s**e# !iete# It "n *s%

#e&*e"t hihe# s+e"t #ti% hs *#e# s'#&"e #e

19


28/58

Figure 1 Cross sectional view of Zn nanowires

20


29/58

Figure 11 Cross sectional view of #i2coated Zn nanowires

1)* S'&c&'!l !n!l7$%$ o# "!'e 8nO n!now%'e$ !nd T%O*co!ed 8nO n!now%'e$

3hi*i+s 3e#t RD is 'se! t% n*ysis the "hei"* n! "#yst**%#+hi" st#'"t'#e %&

the =nO nn%.i#es n! the e7isten"e %& TiO2"%tin Ste+ .i!th .s set t% 002%n!

tie &%# e"h ste+ .s 1 se"%n! 2 thet #ne .s % 20%t% @0% Fi'#e 12 sh%.s

the RD +tte#n %& =nO nn%.i#es n! ITO s',st#te The#e .s e#y hih +e/ t

;>%.ith %e# ?000 ' intensity The (002) !i&"ti%n +e/ is the hihest sh#+ +e/

in the &i'#e8 tht in!i"tes %st %& =nO nn%.i#es #%.th e#ti"**y t% the ITO

s',st#te8 .hi"h #ees the ies t/en ,y SEM

The '++e# +#t %& &i'#e 1; sh%.s the RD s+e"t#' %& TiO2"%te! =nO nn%.i#es

n! ITO s',st#te The#e *s% e7ists sh#+ +e/ t ;> %,'t .ith 1@>0 ' intensity

.hi"h is in J100K !i#e"ti%n Besi!es8 se"%n! hih sh#+ +e/ e7ists t ;2%.ith 900

' intensity .hi"h is in J100K !i#e"ti%n The *%.e# +#t %& &i'#e 1; sh%.s the (+!& n%

010-21) TiO2stn!#! !i&"ti%n +e/s The#e .e#e s%e +e/s t"hes *i/e t

;2% n! ;?% D'e t% the ,"/#%'n! n%ise n! the hih intensity %& =nO nn%.i#es

!i&"ti%n +e/s8 the TiO2 !i&"ti%n +e/s .i** n%t ,e "*e#*y sh%.n Sin"e the TiO 2

*ye# is e#y thin n! the 'ntity is #e*tie*y s** "%+#e t% =nO nn%.i#es8 s%

the *itt*e +e/s "nn%t ,e seen in the &i'#e

21


30/58


31/58

Figure 1" 678 pattern of #i2coated Zn nanowires and 9# su:strate

1), C&'+e$ !n!l7$%$ o# 06ooc&''en +e'$e$ +ol!ge g'!06

S%*# sti'*ti%n test .s 'se! t% %,tin the #e*ti%nshi+ ,et.een %*te n!

+h%t%"'##ent %& DSSCs O+en "i#"'it %*te (%") is the %*te .hen the

+h%t%"'##ent is $e#%8 .hi*e sh%#t "i#"'it +h%t%"'##ent (Is") is the "'##ent .hen %*te

is $e#% Sh%#t "i#"'it +h%t%"'##ent !ensity (s") is the sh%#t "i#"'it +h%t%"'##ent +e#

'nit #e The DSSC s+*es .e#e teste! 'n!e# stn!#! %& AM 1>8 in .hi"h the

DSSCs .e#e si'*te! 'n!e# stn!#! s%*# *iht intensity %& 100062 .ith

.e*enth5 ;@0-90 n J?K

The#e .e#e t%t**y 2@ DSSCs ,ein teste! 'n!e# AM 1> They .e#e &,#i"tin t

!i&&e#ent "%n!iti%ns DSSCs .ith =nO nn%.i#es %n*y .e#e t#ete! s "%nt#%* #%'+

The#e .e#e th#ee #%'+s %& DSSC .ith TiO 2 "%te! =nO nn%.i#es in %7yen t%

#%n s #ti% 151 eni#%nent n! !e+%sit TiO2 &%# >8 10 n! 1> in'tes An%the#

th#ee #%'+s %& DSSC .ith TiO2"%te! =nO nn%.i#es in %7yen t% #%n s #ti%

251 eni#%nent n! !e+%sit TiO2 &%# >8 10 n! 1> in'tes T%t**y seen #%'+s8

e"h #%'+ hs < s+*es They .e#e ** s"#+e! the =nO nn%.i#es .ith %n*y

02>"2*e&t s the e&&e"tie #e

The e#e sh%#t "i#"'it +h%t%"'##ent n! %+en "i#"'it %*te %& =nO nn%.i#es

.e#e 00@ A n! 0> 6hi*e TiO2 "%te! =nO nn%.i#es in s #ti% 251

!e+%sit &%# 1> in'tes .e#e 0;1 A n! 0?


32/58

The e7+e#ient* !t % th#ee e7+e#ient* #%'+s8 "%nt#%*8 151 n! 251 %7yen-

t%-#%n s #ti% #%'+s t !i&&e#ent !e+%siti%n ties %& >8 108 n! 1> in'tes .e#e

"%**e"te! n! +*%tte! the e#e +h%t%"'##ent inst %*te s &%**%.s5

Figure 1% 3verage 0&otocurrent- ;oltage curve a$ong different groups

2


33/58

Fi'#e 1> is the Ae#e 3h%t%"'##ent- %*te "'#e %& TiO2 "%te! DSSC in s

#ti% 151 !e+%sit &%# >8 108 1> in'tes C'#e %& 151 n! 1> in'tes !e+%siti%n hs the

*#est Is"n! %"8 .hi"h is hihe# thn 10 in'tes #%'+ n! "%nt#%* #%'+ 6hi*e

"'#e %& s #ti% 151 !e+%sit &%# > in'tes hs the *%.est Is"n! %" .hi"h een

*%.e# thn "%nt#%* #%'+

Figure 1+ 3verage 0&otocurrent- ;oltage curve of #i2coated 8SSC in gas ratio 11

deposit for +4 14 1+ $inutes and control

2>


34/58

Fi'#e 1? is the e#e +h%t%"'##ent-%*te "'#e %& TiO2

"%te! DSSC in s #ti%

251 !e+%sit &%# >8 108 1> in'tes C'#e %& 251 1> in'tes *s% hs the *#est I s"n!

%"8 .hi"h is hihe# thn 10 in'tes #%'+ n! "%nt#%* #%'+ 6hi*e "'#e %& s

#ti% 251 !e+%sit &%# > in'tes *s% hs the *%.est I s"n! %" .hi"h een *%.e# thn

"%nt#%* #%'+

Figure1/ 3verage 0&otocurrent- ;oltage curve of #i2coated 8SSC in gas ratio 21

deposit for +4 14 1+ $inutes and control

2?


35/58

1). D7e $en$%%;ed $ol!' cell$ 0e'#o'm!nce !nd e##%c%enc%e$

DSSCs .e#e teste! 'n!e# stn!#! test t% stn!#!i$e the +h%t%%*ti"

+e#&%#n"e-- AM 1> The e&&i"ien"y () %& DSSC "n ,e !ete#ine! ,y

FF 7 Is"7 %" L

.he#e FF37 (Is"7 %") n! L is *iht intensity (100062)

Fi** F"t%# (FF) is the #ti% %& 7i' +%.e# %'t+'t t% the +#%!'"t %& sh%#t "i#"'it

+h%t%"'##ent n! %+en "i#"'it %*te %& DSSC A *#e# FF ens the DSSC &%**%.s

"*%se# t% the i!e* +#%+e#ties %& sei"%n!'"t%# T,*e 1 sh%.s the +h%t%e*e"t#i"

+#ete#s %& < +ie"es =nO nn%.i#es ,se DSSCs n! 2< +ie"es DSSCs .ith TiO2

"%te! =nO nn%.i#es

The hihest e&&i"ien"y "hiee! in the t,*e is 0

in'tes DSSC (C1>-1)8 .hi*e the *%.est e&&i"ien"y "hiee! in the t,*e is 002

.hi"h is TiO2

"%te! =nO nn%.i#es in %7yen t% #%n s #ti% 151 eni#%nent

n! !e+%sit TiO2&%# > in'tes DSSC (B0>-2)

2


36/58

Elec'ode S!m0le G!$ R!%o (O2:Ar) Co!%ng T%me (min) Voc (V) I$c (mA) F%ll F!co' E##%c%enc7 (%)

Zn

-; 11 1+ !2+ 2!% %/% "/5

B1>-< 11 1+ /+

(0.#8!)

2"2

(0.25#)

%5"

(0.475)

2!!

(0.!!!)

C0>-1 21 + /"+ !1 %+" .2

C0>-2 21 + +++ /. %/2 !%

C0>-; 21 + /2+ !% %"+ .1%

C0>-< 21 + +!+

(0.58)

."

(0.074)

%//

(0.454)

5

(0.08")

C10-1 21 1 /"+ 1! +% 2"%

C10-2 21 1 /%+ 1. +2! 2+"

C10-; 21 1 /%+ 15 ++% 2!1

C10-< 21 1 /"+

(0.#40)

1/5

(0."52)

+"/

(0.5!)

2"

(0.247)

2@


37/58

C1>-1 21 1+ /++ "%! +2+ %!.

C1>-2 21 1+ /%+ "21 +15 %"

C1>-; 21 1+ /2+ 2// +2 ""%

C1>-< 21 1+ /%+(0.#4!)

"" +15(0.!"7) (0.5"#)

%%/(0.422)

1)1 S!%$%c!l !n!l7$%$

The e7+e#ient* !t % th#ee s #ti% #%'+s t #i%'s !e+%siti%n ties .e#e

"%**e"te! n! n*y$e! *t%ethe# t% e+hsi$e "%+#tie s+e"ts ,y 'sin S3SS

1>0 n! E7"e* 200 Re#!in t% s** s+*e si$es8 the !ist#i,'ti%n %& the !t

!eite! st#%n*y % n%#*ity n! the #in"es %& the th#ee #%'+s %&

e7+e#ient* !t .e#e n%t e'* Th's8 n%n-+#et#i" .s 'se! &%# !t n*ysis

Des"#i+tie !t .e#e +#esente! n! "%##e"te! t% th#ee !e"i* +*"es Sttisti"*

sini&i"n"e .s set t U 00> *ee*

*ffect of 8eposition #i$e on t&e *fficiency of t&e Solar Cells

N%n-+#et#i" %ne-.y ,et.een-#%'+s n*ysis %& #in"e (ANOA) .s 'se! t%

test8 %n e#e8 the e&&e"t %& the !e+%siti%n ties %& the s%*# "e** in &&e"tin the

e&&i"ien"y %& the s%*# "e** The #es'*t %,tine! % n%n-+#et#i" %ne-.y

,et.een-#%'+s ANOA %n e&&i"ien"y sh%.e! sini&i"nt !i&&e#en"e .ith

sy+t%ti"**yF!ist#i,'te! 92>;08p 000 t the 0> *ee*

In %#!e# t% test .hi"h s',4e"t #%'+s .e#e sini&i"n"e %n e"h %& the e&&e"t8 0ost

=oc #est.s +e#&%#e! Res'*ts %#u>ey =S8sh%.n tht8 %n*y the > in'tes

#%'+ (+ 2>;) sh%.e! n% sini&i"nt !i&&e#ent t% the "%nt#%* #%'+8 .hi"h !i! n%t

'n!e#% ny !e+%siti%n (ie5 0 in'tes) B%th 1> in'tes8 10 in'tes #%'+s .e#e

sini&i"nt !i&&e#ent ,et.een %the# !e+%siti%n tie #%'+s n! *s% the "%nt#%* #%'+8

.ith ,%thp 000 t the 0> *ee*See statistics data 1a)

29


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6ithin s #ti% #%'+ "%+#is%ns %& e&&i"ien"y t !i&&e#ent !e+%siti%n ties .e#e

*s% +e#&%#e! t% test the e&&e"t %& the !e+%siti%n ties %& the s%*# "e** in &&e"tin

the e&&i"ien"y %& the s%*# "e** .ithin e"h s #ti% Res'*ts %#u>ey =S8sh%.e!

tht8 the e&&i"ien"y %& s%*# "e**s t !i&&e#ent !e+%siti%n ties .ithin 151 %7yen-t%-

#%n #%'+ .s sini&i"nt8 .ith F(181>) 10@;08 p000 t U 0> n! th#ee

!e+%siti%n tie #%'+s8 > in'tes8 10 in'tes 8 n! 1> in'tes #%'+ .e#e n%t

h%%en%'s % e"h %the# See statistics data 1:)Sini&i"nt #es'*t *s% %,tine!

% 251 %7yen-t%-#%n #%'+8 .ith sy+t%ti"**yF!ist#i,'te! 9@2 n! th#ee !e+%siti%n tie #%'+s .e#e *s% &%# !i&&e#ent h%%en%'s

#%'+s See statistics data 1c)

*ffect of ?as 7atio of @ygen-to-3rgon to t&e *fficiency of t&e Solar Cell

N%n-+#et#i" %ne-.y ,et.een-#%'+s ANOA .s 'se! t% e7ine the s #ti%

e&&e"t in &&e"tin the e&&i"ien"y %& the s%*# "e** The #es'*t %,tine! sh%.e! n%

sini&i"nt !i&&e#en"e .ith sy+t%ti"**y F!ist#i,'te! 2;@?8 p 11; t the 0>

*ee* In %#!e# t% test .hi"h s',4e"t #%'+s .e#e insini&i"n"e %n e"h %& the

e&&e"t80ost =oc #est.s +e#&%#e! Res'*ts %#u>ey =S8sh%.n tht8 the 251 s

#ti% #%'+ (+ 01


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%,tine! sh%.e! sini&i"nt !i&&e#en"e8 .ith sy+t%ti"**yF!ist#i,'te! 1;2??8

p 000 t the 0> *ee* See statistics data 2:) 6hi*e the #es'*t %,tine! % 10

in'tes !e+%siti%n tie #%'+ *s% sh%.e! sini&i"nt !i&&e#ent8 .ith F(181>)

1@ See statistics data 2c) F%# 1> in'tes !e+%siti%n tie

#%'+8 sini&i"nt #es'*t *s% %,tine! .ith sy+t%ti"**yF!ist#i,'te! ?2208p

000 t the 0> *ee* See statistics data 2d)

1)2 E##ec$ o# ' $0'!7 $eed%ng me6od

Fi'#e 1 n! 1@ sh%.s the =nO nn%.i#es 'sin s+#y see!in eth%! sin s+#y

see!in eth%! "n "hiee hih s+e"t #ti% %& =nO nn%.i#es .hi"h .s ,%'t

20 The =nO nn%.i#es #e. .ith *%n nn%.i#e n! s** !iete# !'e the see!s

s+#e! een*y %n ITO s'#&"e Oe# th%'sn!s %& *itt*e ethn%* !#%+*ets "%ntinin

=in" "ette s+#y %n the ITO8 the !istn"e ,et.een e"h !#%+*et .e#e e#y s**

F'#the#%#e8 the s'#&"e tensi%n %& ethn%* is e#y s** .hi"h enhn"e the see!

s+#e! ** #%'n! the ITO s'#&"e The !ntes %& this eth%! #e si+*e8 .hi"h

#e!'"e the &,#i"ti%n tie n! "%sts "%+#e! t% %the# eth%!s *i/e net#%n

s+'tte#in !e+%siti%n n! CD A*s% !yes "n &i** int% the s+"e n! tt"h t% =nO

nn%.i#es

;1


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Fi'#e 1 =nO nn%.i#es 'sin s+#y see!in eth%!

;2


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Fi'#e 1@ =nO nn%.i#es 'sin s+#y see!in eth%!

1)3 E##ec$ o# g'ow6 c7cle$ o# 8nO n!now%'e$

=nO nn%.i#es .e#e n%t e#e! t%ethe# &te# #e. &%# ; "y"*es Bet.een e"h "y"*e8

the s+*e .s #inse +#eentin *#e =nO *%e#tes ++e# %n the see!e!

s'#&"e The %#e #%.th "y"*es8 the *%ne# =nO nn%.i#es #e. B't *s% in"#ese

the !iete# %& =nO nn%.i#es The#e y e7ist n '*tite #%.th "y"*e .hi"h

"hiee *%n n! thin =nO nn%.i#es

1)4 E##ec$ o# 6e T%O*co!%ng e##ec$ !nd co!%ng me6od$

TiO2hs hih #e"tie in!e7 .hi"h is t#ns+#ent in the isi,*e n! ne#-in#e!

#ne8 s% it is s'it,*e te#i* &%# "%tin TiO 2 *ye# +#%i!e! *%.e# ene#y stte

t% *et !yes e7"ite %#e esi*yJ1-19K The "h#e in4e"ti%n e&&i"ien"y .i** *s% ,e

in"#ese! 3#e+#ti%n eth%!8 "#yst**ine st#'"t'#e n! nne*in te+e#t'#e #e the

&"t%#s tht &&e"t the +h%t%"t*yti" "tiity %& TiO2 thin &i*s J20-2;K E*e"t#%ns

%eents #e #e*te! t% the "#yst**ite si$e n! the sh+e %& TiO 2 D'e t% 'nt'

si$e e&&e"t8 ,n! + %& TiO2in"#eses n! the ,n! e!es shi&t t% yie*! *#e# #e!%7

+%tenti*s8 th's i+#%e the +h%t%"t*yti" "tiity n! +h%t%e&&i"ien"ies The

!i&&'si%n #te %& the e*e"t#%ns n! h%*es ,e"%e &ste# J2;-2K F'#the#%#e8 TiO2

+#%i!e n ene#y ,##ie# .hi"h "n #e!'"e the #e"%,inti%n #te

sin DC net#%n s+'tte#in t% !e+%sit TiO2 %nt% =nO nn%.i#es "n +#%i!e

,ette# "%n!'"ti%n +th.y &%# the e7"ite! e*e"t#%ns n! *#e# !ye ,s%#+ti%n #e

The i%ns hit the titni' t#et .ith n ene#y ,%e the s'#&"e ,in!in ene#y in the

"h,e#8 then titni' +#ti"*es .e#e e4e"te! %'t n! #e"t .ith %7yen t% &%# TiO 28

&in**y !e+%sit %n =nO nn%.i#es C%nenti%n* TiO2+%.!e#s #e'i#e sti##in !'#in

the #e"ti%n +#%"ess8 ,'t DC net#%n s+'tte#in #e n%t J2@-;1K

;;


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1)9 E##ec$ o# de0o$%%on %me T%O*on 8nO n!now%'e$

The !e+%siti%n tie is !i#e"t*y +#%+%#ti%n* t% the thi"/ness %& TiO2 F%# the 1>

in'tes in %7yen t% #%n s #ti% 251 n! 151 #%'+s8 they +e#&%# the ,est .ith

0

in'tes #%'+s .e#e the *st It is sh%.n tht the e&&i"ien"y hs +%sitie #e*ti%n t%

the !e+%siti%n tie M%#e TiO2 "n !e+%sit %n =nO nn%.i#es ,y iin %#e

!e+%siti%n tie8 *s% the Titni' +#ti"*es e4e"te! %'t ,y i%ns "n he %#e tie t%

#e"t the %7yen t% &%# TiO28 th's the yie*! %& TiO2in"#ese! As #es'*t8 thi"/e#

TiO2 *ye# %,tine!8 n! the e&&i"ien"y "n ,e i+#%e! ,y the +#%+e#ties %& TiO2

*ye# .hi"h !is"'sse! ,%e

> in'tes #%'+s een*y h! +%%#e# e&&i"ien"y thn the "%nt#%* It is ,e"'se the

TiO2+#ti"*es "nn%t *in/ t%ethe#8 *ye# "nn%t ,e &%#e! !'e the sh%#t !e+%siti%n

tie This *e!s the !e"#eses in e*e"t#i"* "%n!'"tiity n! the t#ns+%#t #te %&

e*e"t#%ns A*s% t%% *itt*e TiO2 y !e"#ese the s'#&"e #e8 th's the t%t* %'nt %&

!yes .i** ,e *ess the "%nt#%* #%'+

1)(< E##ec$ o# de0o$%%on g!$ '!%o o# T%O*on 8nO n!now%'e$

The e&&i"ien"y %& s #ti% 251 in %7yen t% #%n #%'+s is hihe# thn 151 #%'+s It

is ,e"'se the hihe# yie*! %& TiO2 &%#e! Sin"e the t%t* n',e# %& %7yen is *#e#

in s #ti% %& 251 Titni' +#ti"*es h! *#e# "hn"e t% #e"t .ith %7yen I& the

%'nt %& %7yen is n%t en%'h %# +#%,,i*ity t% #e"t .ith %7yen is *%.8 Titni'

y &%#s s Ti7Oy.hi"h is 'n!esi#,*e I& TiO2 %*e"'*e ,#e/s .hen ##iin t%

the =nO nn%.i#e8 the /ineti" ene#y is sh#e! t% the t%s8 th's !e"#ese the /ineti"

ene#y n! *e! *ess +#%!'"t

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1)(( Po$$%"le e''o'$ !nd %m0'o+emen$

The#e #e see#* +%ssi,*e e##%#s !'#in the e7+e#ient C%ntinnt y esi*y

st'"/ %n the ITO s'#&"e *i/e !'st S% &%#"e+s .e#e 'se! t% hn!*e s+*es8 n! "%e#

s+*es .hen st%#in s+*es Dyes .e#e esi*y e7"ite! ,y *iht8 s% the e&&i"ien"y %&

DSSC .i** ,e *%.e# s the tie %es %n T/e the !t 4'st &te# sse,*y the DSSC8

n! 'sin n%n- t#ns+#ent s+*e ,%7 t% st%#e t% %i! e7"itti%n Ai# ,',,*es

iht t#++e! in the &i* !'#in +%%# sse,*y 6hi"h y *e! t% e7ist n #e

.hi"h !%es n%t he e*e"t#%*yte8 the ITO n! FTO %& tht #e y *%st in "%nt"t8

.hi"h !e"#ese the e&&e"tie #e8 th's the e&&i"ien"y .i** #et*y !e"#ese Besi!es8

the e&&i"ien"y is *s% #et*y !e"#ese! 'neen*y #e-sse,*y the DSSC The !t

he s%e "hnes t/en ,y AM 1> s%*# si'*t%# .hen the "%nt"t +%int ,et.een

s',st#tes n! .i#es "hnes

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2) Concl&$%on$

A*th%'h the e#e e&&i"ien"y %& the DSSCs .hi"h +#%!'"e! ,y s+#y see!in

eth%! n! !e+%siti%n eth%! %& net#%n s+'tte#in "nn%t ,e enhn"e! t% n

%+ti' hih *ee*8 the e#e e&&i"ien"y %& s%*# "e**s % t.%-t%-%ne %7yen t%

#%n #%'+ .ith !e+%siti%n ties %& &i&teen in'tes is &%'# ties %#e thn tht in

"%nt#%* 'n!e# n si+*e8 &st see!in eth%! t #es%n,*e +#i"e

A*s%8 ,%th #+hi"* n! sttisti"* #es'*ts s'""ess&'**y ie sini&i"nt ei!en"es t%

s'++%#t the hy+%thesis tht the e#e e&&i"ien"y %& the s%*# "e**s in the t.%-t%-%ne

%7yen t% #%n #%'+ is sini&i"nt*y hihe# thn tht in the %ne-t%-%ne %7yen t%

#%n #%'+8 .hi"h is *s% sini&i"nt*y hihe# thn tht in the "%nt#%* #%'+ n! the

e&&i"ien"y %& s%*# "e**s % !e+%siti%n tie %& &i&teen in'tes is hihe# thn tht %&

ten in'tes #%'+8 .hi"h is *s% hihe# thn tht %& &ie in'tes #%'+ Th's8 the

%+ti' *ee* %& n! the "%##e*ti%n ,et.een %7yen t% #%n s #ti% n! !i&&e#ent

!e+%siti%n ties in +#%!'"in hih e&&i"ien"y s%*# "e** is the ne7t i+%#tnt tte#

&%# &'#the# n*ysis

;?


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3) Re#e'ence$

J1K FT %n8 SV Di8 n! 6n8 Reie. %& Re"ent 3#%#ess in

Dye-Sensiti$e! S%*# Ce**s8 A!n"es in O+t%E*e"t#%ni"s8 A#ti"*e ID >;@


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s%*'ti%n n! thei# ++*i"ti%ns %n !ye-sensiti$e! s%*# "e**s8 Mte#i*s Lette#s

?28 ++*i",*e in +#"ti"e[ M%!e**in eiht

3h%t%%*ti" te#i*s .ith #es+e"t t% *iht intensity n! t.% s+e"t#8

Rene.,*e Ene#y 2@8 1@>1-1@?


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"h#"te#isti"s %n the e*e"t#%ni" +#%+e#ties %& the e*e"t#%!e8 C%%#!inti%n

Cheist#y Reie.s 2;81?-1@08 (2009)

J1K M G#t$e*8 Nt'#e


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J21K SF 6n8 TV Tsen8 VR 6n8 CV 6n n! HC L'8 E&&e"t %& =nO

see! *ye#s %n the s%*'ti%n "hei"* #%.th %& =nO nn%#%! ##ys8 Ce#i"s

Inte#nti%n* ;>8 12>>-12?08 (2009)

J22K R Thiti8 C 3t"h#ee8 S T/shi n! V S's''8 E&&i"ient e*e"t#%n

t#ns&e#s in =nO nn%#%! ##ys .ith N19 !ye &%# hy,#i! s%*# "e**s8 S%*i!

Stte E*e"t#%ni"s >;8 1?-1@08 (2009)

J2;K T =hn8 I S'tnt%8 T T'"hi8 T%/'hi#%8 ZB Men8 TN R%8 A

F'4ishi8 H 6tn,e8 T N/%#i n! M #i8 A*2O;-"%te!

nn%+%#%'s TiO2 e*e"t#%!e &%# s%*i!-stte !ye-sensiti$e! s%*# "e**8 S%*#

Ene#y Mte#i*s Y S%*# Ce**s @08 ;1>;2?8 (200;)

J2K 3e#t%n8 S 8 et *8 Sei"%n! S"i Te"hn%*8 2009

J2?K Ne.t%n8 M C8 et *8 3hys C%n& Se#8 200?8 2?8 2>1

J2K L L'h%n8 M S G'!i/sen n! C M Lie,e#8 3hi* T#ns R S%" L%n! A

;?2 (200


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J;0K B Ren n! M G#t$e*8 Nt'#e ;>;(1991) ;

J;1K M G#t$e*8 In%# Che ) ?@) 2091

J;;K C B##e*et8 A B G#eyt/ n! C M Lie,e#8 Nn% Lett < (200


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Statistics data 1: Bit&in 11 o@ygen-to-argon group co$parisons of efficiency at

different deposition ti$es


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Statistics data 1c Bit&in 21 o@ygen-to-argon group co$parisons of efficiency at


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o@ygen-to-argon


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Statistics data 2: Bit&in + $inutes group co$parisons of efficiency at different gas

ratio of o@ygen-to-argon


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Statistics data 2d Bit&in 1+ $inutes group co$parisons of efficiency at different gas


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Of the High Performance Gallium Arsenide (GaAs) Nanowires (NWs)

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Transcript of Of the High Performance Gallium Arsenide (GaAs) Nanowires (NWs)