An on-demand solar hydrogen-evolution system for unassisted high-efficiency pure-water splitting

Article abstract of DOI:10.1039/c9ta05142b

Solar water splitting of pure water offers an attractive means for sustainable and carbon-free H₂ production. However, current photocatalytic H₂ production systems still suffer from two basic issues: the kinetic bottleneck for O₂ release and the easy toxicity of the photocatalysts. Here, we developed a consolidated photocatalyst, namely g-C₃N_3.5(O_0.5H_0.5), that can boost sustainable and superior H₂ evolution without using any sacrificial reagent. By conceptual design analysis as the guideline for three synthetic steps, the surface hydroxylation structure of g-C₃N_3.5(O_0.5H_0.5) concurrently increases the toxicity resistance and maximizes the charge separation for H₂ evolution. The obtained surface-hydroxylated g-C₃N_3.5(O_0.5H_0.5) photocatalyst exhibited unassisted high-efficiency pure-water-splitting activity, with a benchmark H₂-evolution rate up to 947.7 μmol h^-1 g^-1 under visible-light irradiation. Notably, the quantum efficiency of the g-C₃N_3.5(O_0.5H_0.5) suspension reached ～10.6 and ～2.5% at 420 and 520 nm, respectively, 10-20 times that of pristine g-C₃N₄. For the first time, we observed a key phenomenon that H₂O molecules can rapidly capture the photoexcited holes to produce H₂O₂, which can greatly promote the efficient charge separation for high H₂ evolution.

Full text of DOI:10.1039/c9ta05142b

View Article Online
View Journal
Journal of
Materials Chemistry A
Materials for energy and sustainability
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: W. Che, H. Su, X.
Zhao, Y. Li, H. Zhang, W. Zhou, M. Liu, W. Cheng, F. Hu and Q. Liu, J. Mater. Chem. A, 2019, DOI:
10.1039/C9TA05142B.
Volume
Number 12
28 March 2018
Pages 4883-5230
6
This is an Accepted Manuscript, which has been through the
Royal Society of Chemistry peer review process and has been
accepted for publication.
Journal of
Materials Chemistry A
Materials for energy and sustainability
rsc.li/materials-a
Accepted Manuscripts are published online shortly after acceptance,
before technical editing, formatting and proof reading. Using this free
service, authors can make their results available to the community, in
citable form, before we publish the edited article. We will replace this
Accepted Manuscript with the edited and formatted Advance Article as
soon as it is available.
You can find more information about Accepted Manuscripts in the
Information for Authors.
Please note that technical editing may introduce minor changes to the
text and/or graphics, which may alter content. The journal’s standard
Terms & Conditions and the Ethical guidelines still apply. In no event
shall the Royal Society of Chemistry be held responsible for any errors
or omissions in this Accepted Manuscript or any consequences arising
from the use of any information it contains.
ISSN 2050-7488
COMMUNICATION
Zhenhai Wen et al.
An electrochemically neutralized energy-assisted low-cost
acid-alkaline electrolyzer for energy-saving electrolysis
hydrogen generation
rsc.li/materials-a

Page 1 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
Table of Contents Entry
H2
-
a
CB - e
O2
H2O
b
VB - h+
c
e
O2
d
Dissociation
in the dark
H2O2
+
+
Superoxo radical
A surface hydroxylation structure of g-C3N3.5(O0.5H0.5) photocatalyst was designed
to concurrently increases the toxicity resistance and maximizes the charge separation
for H2 evolution.

Journal of Materials Chemistry A
Page 2 of 21
View Article Online
DOI: 10.1039/C9TA05142B
A !"#$"%&!$ ' (&) *+$) ,"!#"- (./0 ! '+'/"% 1 ) .!&''0'/"$
*0,*#"11020"!2+ 3.)" 4&/") '3(0//0!,
!" #$!%& '(" )(%& *( +$,-%& .(,/0" 1"%&%2 '(" +$,/3%& ,/0"/ +$-(%& 4!"$(,/ 1"(%& !"5!/
#$!/3%& 6!/37$(/ '(%& ,/8 9"/3$(, 1"(&%:
&
!"#$%!& '(%)*+$"+$% ,!-#!"#$% .!/$+!"$+(0 1%#23+4#"( $5 ')#3%)3 !%- 63)*%$&$7( $5 8*#%!0
9353# :;<<:=0 A%*>#0 ?@ ,@ 8*#%!
2A>%-!B3%"!& ')#3%)3 $% >)&3!+ C!4"3+4 !%- D%2#+$%B3%"!& '!53"( .!/$+!"$+(0 '$>"*E34"
1%#23+4#"( $5 ')#3%)3 !%- 63)*%$&$7(0 F#!%(!%7 G:H<H<0 '#)*>!%0 ?@ ,@ 8*#%!
:;<=,"0> ?$0"(@(AB7C!8(C7/
A5'/)&2/
)-0,5 D,B!5 AE0"BB"/3 "/ E(5! D,B!5 -FF!5A ,/ ,BB5,7B"G! =!,/A F-5 A(AB,"/,H0! ,/8
7,5H-/<F5!! '2 E5-8(7B"-/C '-D!G!5% B$! E$-B-7,B,0IB"7 '2 E5-8(7B"-/ AIAB!=A AB"00
A(FF!5 BD- H,A"7 "AA(!A> B$! J"/!B"7 H-BB0!/!7J F-5 K2 5!0!,A! ,/8 B$! !,AI B-L"7"BI -F
E$-B-7,B,0IABAC '!5!% D! 8!G!0-E , 7-/A-0"8,B!8 E$-B-7,B,0IAB% 3<#MNMCOPKQCO'QCOR% B$,B
7,/ H--AB A(AB,"/,H0! ,/8 A(E!5"-5 '2 !G-0(B"-/ D"B$-(B (A"/3 ,/I A,75"F"7",0 5!,3!/BC
SI 7-/7!EB(,0 8!A"3/ ,/,0IA"A ,A B$! 3("8!0"/! -F B$5!! AI/B$!B"7 AB!EA% B$! A(5F,7!
$I85-LI0,B"-/ AB5(7B(5! -F 3<#MNMCOPKQCO'QCOR 7-/7(55!/B0I "/75!,A!A B$! B-L"7"BI
5!A"AB,/7! ,/8 =,L"="T!A B$! 7$,53! A!E,5,B"-/ F-5 '2 !G-0(B"-/C U$! -HB,"/!8
A(5F,7!<$I85-LI0,B!8 3<#MNMCOPKQCO'QCOR E$-B-7,B,0IAB !L$"H"BA ,/ (/,AA"AB!8
$"3$<!FF"7"!/7I E(5! D,B!5 AE0"BB"/3 ,7B"G"BI% D"B$ B$! H!/7$=,5J"/3 '2<!G-0G"/3 5,B!
(E B- VWXCX Y=-0 $<& 3<& (/8!5 G"A"H0! 0"3$B "55,8",B"-/C N-B,H0I% B$! ?(,/B(= !FF"7"!/7I
-F B$! 3<#MNMCOPKQCO'QCOR A(AE!/A"-/ 5!,7$!A B- Z&QC[ ,/8 Z2CO\ ,B W2Q ,/8 O2Q /=%
5!AE!7B"G!0I% &Q]2Q B"=!A B$,B -F E5"AB"/! 3<#MNWC 6-5 B$! F"5AB B"=!% D! $,G! -HA!5G!8
, J!I E$!/-=!/-/ B$,B '2K =-0!7(0! F,AB 7,EB(5!A B$! E$-B-!L7"B!8 $-0!A B- E5-8(7!
'2K2 B$,B 7,/ 35!,B0I E5-=-B! B$! !FF"7"!/B 7$,53! A!E,5,B"-/ F-5 $"3$ '2 !G-0(B"-/C
6"+4 )$'7 K/!<8!=,/8^ _$-B-5!,7B"-/^ 'I85-3!/ E5-8(7B"-/^ _(5! D,B!5 AE0"BB"/3C

Page 3 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
8!/) $.2/0 !
U$! E$-B-AI/B$!A"A "/ /,B(5! E5-G"8!A , 0(L(5",/B H0(!E5"/B F-5 AB-5"/3 A(/0"3$B "/
7$!="7,0 F-5=% D$"7$ "A ,/ "/8"AE!/A,H0! AB!E B- ,EE0I , E-B!/B",00I A7,0,H0! ,/8
!7-/-="7,00I F!,A"H0! B!7$/-0-3I F-5 A-0G"/3 B$! E5-H0!= -F !/!53I 75"A"AC&%2 KF B$!
E-AA"H0! AB-5,3! =!B$-8A% A(/<85"G!/ D,B!5 AE0"BB"/3 HI A!="7-/8(7B-5A H!,5A J!I
E5-7!AA!A "/ "="B,B"/3 /,B(5,0 E$-B-AI/B$!A"AC )"/7! B$! F"5AB 8"A7-G!5I -F
E$-B-!0!7B5-7$!="7,0 D,B!5 AE0"BB"/3 HI 6(`"A$"=, ,/8 '-/8, -/ U"K2<E$-B-7,B,0IT!8
D,B!5 AE0"BB"/3% B$!5! $,A =(7$ E5-35!AA "/ H,/8<3,E $I85-3!/ E5-8(7B"-/ AIAB!=C
N!D E5!E,5,B"-/ B!7$/-0-3I% /!D 7,B,0IB"7 AB5(7B(5! ,/8 /!D 7,B,0IB"7 =!7$,/"A=
$!0E B- E5-E!0 B$! /!-B!5"7 7,B,0IB"7 AIAB!=A B$,B $,G! H!!/ AB(8"!8 "/ 8!EB$CM]V S!"/3
B$! A"=E0!AB D,B!5<AE0"BB"/3 E,B$D,I% B$! E$-B-7,B,0IA"A B- E(5A(! -G!5,00 D,B!5
AE0"BB"/3 PK )R B-D,58 0"3$B<"55,8",B!8 E-D8!5 A(AE!/A"-/ $,A ,BB5,7B!8 "/B!/A"G!
"/B!5!AB 8(! B- B$! A"=E0"7"BI ,/8 0-D -E!5,B"-/,0 7-ABC 4!,/D$"0!% , /(=H!5 -F BIE!A
-F E,5B"7(0,B! AIAB!=A F-5 K ) $,G! H!!/ !/G"A,3!8 "/ B$! !,50I &VaQAC "B$ B$!
=!7$,/"A= "8!/B"F"!8% bC c-=!/ D,A B$! F"5AB B- 5!E-5B E,5B"7(0,B! N"K<)5U"KM
7,B,0IABA B$,B ,7B!8 ,A BD- 5-0!A% '2 3!/!5,B-5A ,/8 K2 3!/!5,B-5A "/ K ) AIAB!= "/
&VaQ P)(EE-5B"/3 d/F-5=,B"-/% )M !?(,B"-/ &RC&Q%&& U$! B!5=!8 +<A7$!=! !LE!5"=!/BA
<
F-5 K )% _BeU"K2 P,/,B,A!% 5(B"0!R E$-B-7,B,0IABA D"B$ dKM ed< 5!8-L =!8",B"-/% $,A
H!!/ E!5F-5=!8 ,/8 B$! '2 E5-8(7B"-/ D,A 5!E-5B!8 ,B 2OQ Y=-0 $<& 3<& PWQQ '3
0,=ERC&2%&M 6(5B$!5=-5!% U,/3 3" !&C $,G! E5-G"8!8 B$! !G"8!/7! B$,B !,7$ =-0!7(0! -F
-LI3!/ !G-0G!8 F5-= BD- D,B!5 =-0!7(0!A 5!?("5!A F-(5 E$-B-/Ae$-0!A% -FF!5"/3 B$!
F,7B-5A B$,B /!!8 B- H! ,885!AA!8 B- E5-=-B! B$! !FF"7"!/7I -F K )C&W
A0B$-(3$ A-0,5<85"G!/ D,B!5<AE0"BB"/3 AIAB!=A ,/8 7-/A"8!5,H0! =!7$,/"A=A
7-/7!5/!8 $,G! H!!/ "8!/B"F"!8 "/ B$! E,AB I!,5A% "B 5!=,"/A "/B5"/A"7 H-BB0!/!7JA B$,B
$,=E!5 "BA E5,7B"7,0 (B"0"T,B"-/C dB D,A 5!E-5B!8 B$,B E!5-L"8!A AE-/B,/!-(A0I -77(5
F5-= H-B$ '2 3!/!5,B-5A ,/8 K2 3!/!5,B-5A "/ K ) ,/8 0,53!0I 8!75!,A!A B$! ,7B"G"BI
B- 7-/G!5B A-0,5<'2 !/!53I P)(EE-5B"/3 d/F-5=,B"-/% )M !?(,B"-/ W<X% &QRC U$"A =!,/A
B$! 7-/8(7B"-/ H,/8 P#SR -F A!="7-/8(7B-5 E$-B-7,B,0IAB "A ,7B"G! F-5 B$!
E$-B-5!8(7B"-/ -F K2 D$"7$ "A E5-8(7!8 G", F-(5<!0!7B5-/ E5-7!AA "/ G,0!/7! H,/8
PfSR P)(EE-5B"/3 d/F-5=,B"-/ F-5 B$! E$-B-5!8(7B"-/ -F K2% )M !?(,B"-/ W<XRC K/ B$!
-B$!5 A"8!% , $"3$!5 5!,7B"-/ 5,B! =,I H! ,7$"!G!8 "/ =-AB A!="7-/8(7B-5A D$!5! B$!
!

Journal of Materials Chemistry A
Page 4 of 21
View Article Online
DOI: 10.1039/C9TA05142B
G,0!/7! H,/8 PfS% g&CXa !fR ,7BA ,A 5!,7B"G! 0!G!0 F-5 , BD-<!0!7B5-/ 5!,7B"-/ B- '2K2
P)(EE-5B"/3 d/F-5=,B"-/% )M !?(,B"-/ &QRC 4-5!-G!5% 0-BA -F F,7BA $,G! H!!/ 5!E-5B!8
B$,B '2K2% , 7$!="7,0 A-(57! -F -LI3!/<7-/B,"/"/3 5,8"7,0A 7-(E0!8 D"B$ , AB5-/3
-L"8"T"/3 !/G"5-/=!/B% -FB!/ E-"A-/A B$! E$-B-7,B,0IABAC&O%&[ 6-5 B$!A! 5!,A-/A%
=!B$-8A ,EE0"!8 B- A!0!7B"G!0I 8!,7B"G,B! B$! 5!G!5A! E5-7!AA!A ,H-G!% ,/8 -EB"="T!
<
B$! A(5F,7! J"/!B"7A B- "/$"H"B B$! 5!,7B"G! -LI3!/ AE!7"!A PhK)% K2 % 9K'% '2K2R R ,5!
8!A"5!8C h!7!/B0I% b,/3 5!E-5B!8 #<8-BAe#MNW /,/-7-=E-A"B! ,7$"!G!8 A-0,5 !/!53I
7-/G!5A"-/ !FF"7"!/7I -F 2\ G", BD-<!0!7B5-/ E,B$D,I% E,G"/3 B$! D,I F-5 ,
E-B!/B",00I 70!,/ ,/8 5!/!D,H0! A-(57! F-5 $I85-3!/ F(!0 P)(EE-5B"/3 d/F-5=,B"-/% )M
!?(,B"-/ 2<MRC&[ S(B H!I-/8 B$,B% F!D !L,=E0!A ,5! !FF!7B"G! "/ 5!,0"T,B"-/ -F K )
8(! B- B$! E5-8(7B"-/ -F hK) -77(55!8 !L70(A"G!0I ,B D,B!5<AE0"BB"/3 (/8!5E-B!/B",0AC&O
U$! F5!?(!/B0I<(A!8 =!B$-8 -F E5!G!/B"/3 5!G!5A! 5!,7B"-/A "A B- 7-/AB5(7B A,75"F"7",0
5!,3!/B 7-/B,"/"/3 D,B!5<AE0"BB"/3 AIAB!=A% D$!5! B$! !0!7B5-/ 8-/-5 A7,G!/3!5A
E5-B!7B =,B!5",0A F5-= E$-B-7-55-A"-/ HI 7-/A(="/3 -L"8"T"/3 $-0!A ,/8 E5-$"H"B"/3
7$,53! 5!7-=H"/,B"-/ E,5!/B$!B"7,00IC '-D!G!5% B$! A,75"F"7",0 ,3!/BA 7,/ H! -L"8"T!8
B- 7,(A! E-00(B"/3 HIE5-8(7BA ,/8 H5"/3 ,H-(B ,88"B"-/,0 A(HA!?(!/B 7-AB H(58!/C
U$(A% "B "A $"3$0I 8!A"5!8 B- 7-/AB5(7B , E$-B-7,B,0IAB B$,B "A 5!0,B"G!0I ,7B"G! F-5
K )% ,/8 5!0,B"G!0I AB,H0! B- 5!A"AB B$! B-L"7"BI -F B$! hK)C '!5!% D! F-7(A -/
3<#MNW% B$! -08!AB 5!E-5B!8 E-0I=!5"7 7,5H-/ /"B5"8!A P_#cR HI 1"!H"3 "/ B$! &aMQAC&X
AA ,/ ,BB5,7B"G! =!B,0<F5!! E$-B-7,B,0IAB% B$! H,/8 3,E !/!53I -F 3<#MNW "A =-8!5,B!
P2CX !fR% D"B$ $"3$ G,0!/7! ,/8 7-/8(7B"-/ H,/8 E-A"B"-/A i&Ca] <QCV G!5A(A B$!
5!G!5A"H0! $I85-3!/ !0!7B5-8! Ph';RjC 6,7"/3 A"="0,5 AB5(330!A% B$! F-5=,B"-/ -F '2K2
"A B$!5=-8I/,="7,00I =-5! F,G-5,H0! B$,/ B$! F-(5<!0!7B5-/ E5-7!AA F-5 K2 !G-0(B"-/%
,/8 B$! ,7B"G"BI -F 3<#MNW ,0A- A(FF!5A F5-= E-"A-/"/3 HI '2K2C&2 ;G!/ =-5!
-="/-(A0I% 8!B!7B,H0! N2 ,5"A!A F5-= A!0F<-L"8,B"-/ HI E$-B-!L7"B!8 $-0!AC&a%&V U-
"=E5-G! "BA "/$!5!/B0I 0-D D,B!5<AE0"BB"/3 ,7B"G"BI% B$! 5,B"-/,0 =-8"F"7,B"-/A ,5!
A(EE-A!8 B- A"=(0B,/!-(A0I "/75!,A! ,7B"G"BI ,/8 AB,H"0"BI -F B$! A(5F,7!C A F"5AB
,EE5-,7$ B$,B 7,/ H! H,A!8 -/ B$! 5!E-5B!8 5!A(0BA "A B$,B B$! 0-D<=-0!7(0,5<D!"3$B
7,5H-/ /"B5"8!A !L$"H"B!8 A(E!5"-5 E$-B-7,B,0IB"7 '2 !G-0(B"-/ "/ B$! A,75"F"7",0
5!,3!/B<7-/B,"/"/3 D,B!5 7-=E,5!8 B- B$!"5 H(0J 7-(/B!5E,5BAC2Q%2& )"3/"F"7,/B0I% B$!
8!A"3/ -F 3<#MNW A$-(08 B,J! B$! 0!,8"/3 "/ 0"H!5,B"/3 =-5! "A-0,B!8 -0"3-=!5A -F
"

Page 5 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
=!0!=% D$"7$ A(HAB,/B",00I !0(7"8,B! B$! ,7B"G! E$,A! -F 0"3$B<5!AE-/A! F-5
E$-B-7,B,0IB"7 '2 ,/8 K2 !G-0(B"-/C AA F-5 B$! F"/8"/3A -/ B$! "/AB,H"0"BI -F 3<#MNW
=,B!5",0A% , E$-B-7,B,0IB"7,00I 5!0!G,/B 8!F!7B "A 7-==-/0I 7-/A"8!5!8 B- H! E!5"E$!5,0
F(/7B"-/,0 35-(EA P<N'2RC d/ H,A"7 D,B!5 AE0"BB"/3 E5-7!AA% B$! A(5F,7! (/<7-/8!/A!8
,="/- 35-(EA P<N'2R 7,/ H! A!0F<-L"8"T!8 HI B$! !L7"B!8 $-0!A ,77-=E,/"!8 HI N2 3,A
!G-0(B"-/C22 6(5B$!5=-5!% B$! (/<7-/8!/A!8 ,="/- 35-(EA =-"!BI 8"AB5"H(B!8 "/ B$!
A(5F,7! "A "8!/B"F"!8 ,A B$! /!D0I<7-="/3 7,55"!5 5!7-=H"/,B"-/ 7!/B!5C2M _,5B"7(0,50I%
B$! A!7-/8 ,EE5-,7$ F-5 F"L"/3 B$! 8!F!7BA H,A!8 -/ B$! ,H-G! ,/,0IA"A ,/8 B$!-5!B"7,0
E5!8"7B"-/ "/B5"/A"7,00I A,B"AFI B$! ,F-5!=!/B"-/!8 75"B!5", "/ K )C
'!5!% D! $,G! !0,H-5,B!0I 8!G!0-E!8 , /!D BIE! -F A(5F,7! $I85-LI0,B!8
E$-B-7,B,0IABA% 3<#MNMCOPKQCO'QCOR% G", , 7-/7!EB(,0 8!A"3/ ,A 8!E"7B!8 HI B$!
A7$!=,B"7,0 B,7B"7A "/ )7$!=! &C U$! (/"?(! A(5F,7! $I85-LI0,B"-/ !FF!7B"G!0I
A(EE5!AA!A B$! E$-B-7,55"!5 5!7-=H"/,B"-/% E5-0-/3A B$! E$-B-7,55"!5 0"F!B"=!% ,/8
"/75!,A!A B$! B-L"7"BI 5!A"AB,/7! -F hK)C '!/7!% D"B$-(B ,88"B"-/ -F A,75"F"7",0 5!,3!/B%
, H!/7$=,5J"/3 '2<!G-0G"/3 5,B! F-5 B$! 3<#MNMCOPKQCO'QCOR E$-B-7,B,0IAB (/8!5 G"A"H0!
0"3$B Pk MQQ /=R "55,8",B"-/ (E B- VWXCX Y=-0 $<&3<& D,A ,7$"!G!8% ,H-(B &W B"=!A
!/$,/7!=!/B "/ 7-=E,5"A-/ D"B$ B$,B -F E(5! 7,5H-/ /"B5"8!AC 4-5!-G!5% ?(,/B(=
!FF"7"!/7"!A -F &QC[\ ,B W2Q /= ,/8 2CO\ ,B 0-/3!5 G"A"H0! 0"3$B D,G!0!/3B$ -F O2Q /=
D!5! -HB,"/!8 F-5 B$! 3<#MNMCOPKQCO'QCOR A(AE!/A"-/ "/ E(5! D,B!5C 6(5B$!5
"/G!AB"3,B"-/A -/ B$! !/3"/!!5!8 7-/F"3(5,B"-/ B- E5!G!/B B$! B-L"7"BI -F hK) ,5!
7-/F"5=!8C AA !LE!7B!8% B"=! 7-(5A! -F '2 E5-8(7B"-/ 5!=,"/A /- /-B"7!,H0! 8!75!,A!
8(5"/3 B$! MQ<$-(5 B!ABC "B$ B$! 0-/3<B!5= AB,H"0"BI ,/8 , $"3$ !FF"7"!/7I -F '2
!G-0(B"-/% B$! E5-7!AA!A -F 0"/3!5"/3 5!0!,A! -F K2 (/8!5 0"3$B ,/8 5,E"8 5!0!,A! -F K2
"/ B$! 8,5J =,J! B$! '2 E5-8(7B"-/ "/ E(5! D,B!5 E5!F!5!/B",0C 6-5 B$! F"5AB B"=!% D!
$,G! -HA!5G!8 ,/ "/B!5!AB"/3 E$!/-=!/-/ B$,B '2K F,AB 7,EB(5!A B$! E$-B-!L7"B!8
$-0!A B- E5-8(7! '2K2 B$,B E5-E!0A !FF"7"!/B 7$,53! A!E,5,B"-/ F-5 $I85-3!/ !G-0(B"-/
"/ B$! 3<#MNMCOPKQCO'QCOR A(AE!/A"-/C 4-5!-G!5% B$! 5!,7B"G"BI ,/8 A!0!7B"G"BI B-
A!0F<E(=E"/3 E$-B-!L7"B!8 $-0!A HI '2K B- F-5= '2K2 D!5! "8!/B"F"!8C 6"/,00I% B$!
!LE!5"=!/B,0 ,/8 B$!-5!B"7,0 ,/,0IA!A -F 5!,A-/,H0! 7-/7!EB(,0 8!A"3/ B- 7-/AB5(7B
A(5F,7! $I85-LI0,B!8 2c 3<#MNW F-5 A,B"AFI"/3 B$! K ) =,I E5-G"8! F(5B$!5 ,G!/(!A
B- , A(AB,"/,H0! -EB"="T,B"-/ F-5 B$! 7-/G!5A"-/ -F A(/0"3$B B- '2 F(!0AC
#

Journal of Materials Chemistry A
Page 6 of 21
View Article Online
DOI: 10.1039/C9TA05142B

Page 7 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
3<#MNMCOPKQCO'QCOR 70!,50I A$-D , /!,50I B5,/AE,5!/B BD-<8"=!/A"-/,0 /!BD-5JA D"B$
/(=!5-(A E-5! 7$,//!0A B$,B 5(/ B$5-(3$ B$! E-0I=!5AC U$! A(5F,7! ,5!, ,/8 E-5-A"BI
-F 3<#MNMCOPKQCO'QCOR $,A !L,="/!8 HI A-5EB"-/ =!,A(5!=!/BA P6"3(5! )M% U,H0! )&RC
U$! A(5F,7! ,5!, -F E5"=,5I 3<#MNW% 3<#MNMCOPNQCO'&R ,/8 3<#MNMCOPKQCO'QCOR D,A
=!,A(5!8 ,A MM% XX ,/8 VW =2e3% 5!AE!7B"G!0IC U$! N2 ,8A-5EB"-/e8!A-5EB"-/ "A-B$!5=
"/8"7,B!A B$,B B$! E-5! -F 3<#MNMCOPKQCO'QCOR "A "/ B$! ="75-E-5-A"BI% D$"7$ "A =(7$
0,53!5 B$,/ 3<#MNMCOPNQCO'&RC ;=E$,A"T!8 "/ 'hU;4 "=,3! P6"3(5! &7R% B$! E-5!A
$"3$0"3$B!8 HI !00"EB"7 7"570!A 5!A!=H0!8 B5,/AE-5B 7$,//!0 B$5-(3$-(B
3<#MNMCOPKQCO'QCOR =,B5"LC *hc AE!7B5, F-5 F(/7B"-/,0 (/"B ,/8 35,E$"B"7<0"J! 0,I!5
AB5(7B(5! -F "/B!50,I!5 8"AB,/7! ,5! 7-/A"AB!/B F-5 3<#MNMCOPKQCO'QCOR H!0-DC U$!
8"FF5,7B"-/ E!,J ,B PQQ2R "/ 6"3(5! &8 7-/F"5=!8 B$! o]o AB,7J"/3 AB5(7B(5! -F
"/B!50,I!5 8"AB,/7! PMC2Q pR% A(33!AB"/3 B$! AB,H0! AJ!0!B-/ -F 35,E$"B"7<E$,A! #<N
E-0I=!5AC _!,J P&QQR "/8"7,B!8 B$,B B$! F"/3!5E5"/BA ,5! 5!E!,B!8 F(/7B"-/,0 (/"B
-5"3"/,B!8 F5-= =!0!=% $!EB,T"/! P#[NXR D"B$ , AE,7"/3 -F [CV& pC2W
U- "8!/B"FI B$! AB5(7B(5,0 "/B!5F,7",0 8",35,= F-5 3<#MNMCOPKQCO'QCOR% D! E!5F-5=!8
L<5,I ,HA-5EB"-/ /!,5<!83! AE!7B5-A7-EI P*AN;)R% !L7!EB"-/,00I A!/A"B"G! B- 0-7,0
!0!7B5-/"7 7-/F"3(5,B"-/C2O '-D!G!5% "/ N&A *AN;) AE!7B5,% B$! "/F-5=,B"-/ ,H-(B
H-/8"/3 7-/F"3(5,B"-/ -F N ,B-=A "/ B$! A(55-(/8"/3A P6"3(5! &8R 8"AE0,IA , 8"AB"/7B
8"FF!5!/7!C U$! !/B"5! N I<!83! AE!7B5(= -F 3<#MNMCOPKQCO'QCOR $,A , /!3,B"G! A$"FB -F
Z&C2 !f 5!0,B"G! B- 3<#MNMCOPNQCO'&RC U$"A A$"FB A(33!ABA B$! 8"FF!5!/7! "/ B$!
7--58"/,B"-/ !/G"5-/=!/B H!BD!!/ 3<#MNMCOPNQCO'&R ,/8 3<#MNMCOPKQCO'QCORC d=E5!AA!8
D"B$ AB(58"/!AA -F AJ!0!B-/ "/ E-0I=!5"7 #<N /!BD-5JA A$-D/ "/ U;4 "=,3!A ,/8
*hc 7(5G!A% B$! AB5(7B(5,0 7$,/3!A 0"J!0I 7-=! F5-= B$! =,B!5",0 "/B!5F,7!C U$(A% D!
$,G! 7$-A!/ =!0,="/! P4;1% #MNMPN'2RMR ,/8 7I,/(5"7 ,7"8 P#.A% #MNMPK'RMR
D$-A! H,A"7 AB5(7B(5,0 (/"B ,5! B5",T"/! P#MNMR% D"B$ l<N'2m ,/8 l<K'm ,A B!5="/,0
35-(EA% 5!AE!7B"G!0I% D!5! (A!8 ,A ,/,0IB!A F-5 AB5(7B(5,0 7-=E,5"A-/ P6"3(5! )WRC
#-="/3 F5-= , A"="0,5 /"B5-3!/ !/G"5-/=!/B% A"="0,5 8"FF!5!/7!A D!5! -HA!5G!8
H!BD!!/ B$! 7-(E0!A -F 4;1% #.A PB5",T"/! =!=H!5R ,/8 3<#MNMCOPNQCO'&R%
3<#MNMCOPKQCO'QCOR P$!EB,T"/!eB5"<A<B5",T"/! =!=H!5R "/ B$! N &A AE!7B5, P6"3(5! )ORC
U$! 8"FF!5!/7! "/ "/"B",0 E-A"B"-/A B$,B 7-55!AE-/8A B- E!,J E-A"B"-/A -F 4;1 ,/8 #.A
%

Journal of Materials Chemistry A
Page 8 of 21
View Article Online
DOI: 10.1039/C9TA05142B

Page 9 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
I.!2/0 !&( % $.("' &!$ 2&/&(+/02 ) (" 1 ) !"#$"%&!$ DF "- (./0 !
F(/7B"-/,0 (/"B
P,R
F(/7B"-/,0 (/"B
PHR
4;1
4;1
#.A
3<#MNMCOPNQCO'&R
#.A
3<#MNMCOPNQCO'&R
3<#MNMCOPKQCO'QCOR
3<#MNMCOPKQCO
'QCOR
MQQ
WQQ
OQQ
[QQ
XQQ
WQQ
OQQ
[QQ
XQQ
,G!0!/3B$ P/=R
,G!0!/3B$P/=R
P8R
P7R
3<#MNMCOPNQCO'&R
;3 r 2CXa !f
2C& !f
;3 r 2Ca& !f
3<#MNMCOPNQCO'&R
3<#MNMCOPKQCO QCOR
3<#MNMCOPKQCO
'QCOR
&CV !f
'
2CO
MCQ
MCO
Q
O
&Q
&O
S"/8"/3 ;/!53I P!fR
! ! "# $
I0,.)" FC P,R sf<G"A AE!7B5, -F B5",T"/! H,A!8 4;1 ,/8 #.A% $!EB,T"/! H,A!8
3<#MNMCOPNQCO'&R ,/8 3<#MNMCOPKQCO'QCORC PHR _$-B-0(="/!A7!/7! !="AA"-/ 7(5G!A -F B$!
F(/7B"-/,0 (/"BC P7R U,(7ec,G"A<4-BB E0-BA -F 3<#MNMCOPNQCO'&R ,/8 3<#MNMCOPKQCO'QCORC P8R fS
AE!7B5,C
d/ -58!5 B- (/8!5AB,/8 B$! -EB"7,0e!0!7B5-/"7 E5-E!5B"!A -F 3<#MNMCOPKQCO'QCOR "/ 8!EB$%
B$! 7-//!7B"-/ H!BD!!/ F(/7B"-/,0 =-8(0!A ,/8 7,B,0IB"7 5-0! F-5 '2 !G-0(B"-/ D,A
!L,="/!8 HI , G,5"!BI -F 3!/!5,0"T!8 7$,5,7B!5"T,B"-/A ,/8 B!ABAC AA F-5 B$! ,/,0IB!A -F
4;1 ,/8 #.A P6"3(5! 2,R% B$! ,HA-5EB"-/ !83!A "/ B$! sf<G"A ,HA-5EB"-/ AE!7B5, ,5!
H-B$ ,B ,5-(/8 sf H,/8% t WQQ /=C _$-B-0(="/!A7!/7! P_1R =!,A(5!=!/BA "/ 6"3(5!
2H A$-D B$,B B$! !="AA"-/ E!,J -F B$! -EB"7,0 ?(,A"=-/-=!5A H-B$ ,EE!,5!8 ,B ,5-(/8
W&Q /=% ,A B$! F(/7B"-/,0 =-/-7,A! -F B5",T"/! F!,B(5!8 "/ 4;1 ,/8 #.A ,5! B-B,00I
8"FF!5!/B F5-= E-0I=!5"T!8 =-/-=!5 "/ B$! 35-(EA -F 3<#MNMCOPNQCO'&R ,/8
3<#MNMCOPKQCO'QCORC "B$ , AB5-/3 !="AA"-/ E!,J 7!/B!5"/3 ,B ,H-(B WW[ ,/8 WW& /=%
B$! 0(="/!A7!/B H!$,G"-5 -/ 3<#MNMCOPNQCO'&R ,/8 3<#MNMCOPKQCO'QCOR 7,/ H! 8!A75"H!8
B- -EB"7,0 3!/!5,B"-/ -F -0"3-=!5A !L7"B,B"-/A% 8-="/,B!8 HI-EB"7,0 !L7"B,B"-/ D"B$"/
'

Journal of Materials Chemistry A
Page 10 of 21
View Article Online
DOI: 10.1039/C9TA05142B
B$! =!0!= (/"B PB5"<A<B5",T"/!% #[NX<(/"BRC2&%22 d/ 8!B,"0% B$! 7$,5,7B!5"AB"7 2c /!BD-5J
-F 3<#MNMCOPKQCO'QCOR 8-!A /-B $,G! ,5-=,B"7 7-//!7B"-/A PB5",T"/!<B5",T"/! 0"/JR ,0-/3
B$! =!0-/<H,A!8 AJ!0!B-/%2M H!7,(A! B$! 0"/J H!BD!!/ B5"<A<B5",T"/! =-/-=!5 35-DA
-(B -F 7-/AB"B(B!8 B5",/3(0,5 $-0! -/ B$! AB5,/8 ,55,/3!=!/B -F B$! 2c E-0I=!5C U$!
5!A(0BA ,5! 7-/A"AB!/B D"B$ B$! F"/3!5E5"/BA ,B E!,J P&QQR "/ *hc 7(5G!AC U$(A% B$!
E$-B-E$IA"7A -F 3<#MNMCOPKQCO'QCOR H!$,G!A ,A ,/ -EB"7,0 ?(,A"=-/-=!5 -F
l=!0!=<K'mC 65-= B$! E0-B -F U,(7ec,G"A<4-BB% B$! H,/8 3,E !/!53I -F
3<#MNMCOPNQCO'&R ,/8 3<#MNMCOPKQCO'QCOR D,A 7,07(0,B!8 ,A 2CXa ,/8 2Ca& !f%
5!AE!7B"G!0I% D$"7$ "A , 7-=H"/,B"-/ -F B$! 1s4K ,/8 'K4K 0!G!0A -F =!0!=<H,A!8
-0"3-=!5A P6"3(5! 27RC c!5"G!8 F5-= # ET -5H"B,0A% B$! 7-/8(7B"-/ H,/8A -F
3<#MNMCOPKQCO'QCOR ,/8 3<#MNMCOPNQCO'&R D!5! 7,07(0,B!8 B- H! <QCX& ,/8 <QCaa !f B$,B
!/,H0!A B$! 5!8(7B"-/ A"B!A F-5 'u B- '2C $!5!,A% =,"/0I 7-=E-A!8 HI N ET -5H"B,0A%
B$! D,G!F(/7B"-/A -F B$! G,0!/7! H,/8 F-5 3<#MNMCOPKQCO'QCOR "/ fS*_) D!5!
8!B!5="/!8 B- H! 2C& !f P6"3(5! 28R% =(7$ $"3$!5 B$,/ 3<#MNMCOPNQCO'&R P&CV !fRC U$!
0-D!5 _1 "/B!/A"BI -F 3<#MNMCOPKQCO'QCOR "/8"7,B!A B$! A!E,5,B"-/ ,/8 ="35,B"-/ -F
E$-B-<3!/!5,B!8 F5!! 7$,53!A $,G! H!!/ E5-=-B!8C2X 6(5B$!5=-5!% ,77-58"/3 B- B$!
A0-E -F 4-BB<)7$-BBJI 7(5G!A P6"3(5! M,R% B$! 7,55"!5 8!/A"BI -F 3<#MNMCOPKQCO'QCOR "A
85,=,B"7,00I !/$,/7!8 "/ 7-=E,5"A-/ D"B$ B$,B -F 3<#MNMCOPNQCO'&R% D$"7$ "A 8!/-B!8
,A ,/ "=E-5B,/B F,7B-5 B- AB"=(0,B! !FF"7"!/B A-0,5<85"G!/ D,B!5 AE0"BB"/3C2a U$(A% H,A!8
-/ B$! "=E5-G!8 !0!7B5-/"7 E!5F-5=,/7! "/G-0G!8 "/ E$-B-5!8-L 5!,7B"-/% , H!BB!5
E$-B-7,B,0IB"7 ,7B"G"BI 7,/ H! !/G"A,3!8C
U$! E$-B-7,B,0IB"7 D,B!5<AE0"BB"/3 E!5F-5=,/7!A -F B$! ,A<-HB,"/!8
E$-B-7,B,0IABA D!5! !G,0(,B!8 "/ E(5! D,B!5 D"B$-(B ,/I A,75"F"7",0 5!,3!/BA (/8!5
AB,/8,58 5!,7B"-/ ,/8 =!,A(5!=!/B 7-/8"B"-/A P)!! 8!B,"0A "/ )(EE-5B"/3
d/F-5=,B"-/RC d/ , BIE"7,0 B"=! 7-(5A! -F !G-0(B"-/ -F '2 P6"3(5! MHR%
3<#MNMCOPKQCO'QCOR A$-D!8 (/E5!7!8!/B!8 $"3$ ,7B"G"BI F-5 '2 !G-0(B"-/ ,/8 B$!
7-55!AE-/8"/3 7-/AB,/B '2 !G-0(B"-/ 5,B! $,A H!!/ !AB"=,B!8 (E B- VWXCX Y=-0 $<&3<&%
D$"7$ "A ,H-(B &W B"=!A !/$,/7!=!/B "/ 7-=E,5"A-/ D"B$ B$,B -F 3<#MNMCOPNQCO'&R
P[XC2 Y=-0 $<&3<&R ,/8 &V B"=!A B$,/ H(0J 3<#MNW PO&CQ Y=-0 $<&3<&R% A$-D"/3 B$!
!FF"7"!/B (B"0"T,B"-/ -F G"A"H0!<0"3$B E$-B-/AC d/ 6"3(5! M8% "B 7,/ H! A!!/ B$,B
(

Page 11 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
3<#MNMCOPKQCO'QCOR $-08A $"3$!5 -E!/ 7"57("B G-0B,3! ,/8 !L$"H"BA A0-D!5 E$-B-<G-0B,3!
8!7,I H!$,G"-5 ,FB!5 0"3$B B(5/"/3 -/ -5 -FF% 7-55!AE-/8"/3 B- $"3$0I !FF"7"!/B
!0!7B5-/<$-0! E,"5 A!E,5,B"-/C dB "A 5!,8"0I A!!/ F5-= B$! "/A!B -F 6"3(5! M8 B$,B
0"F!B"=!A -F B$! E$-B-7,55"!5 "/ 3<#MNMCOPKQCO'QCOR ,5! A(HAB,/B",00I E5-0-/3!8 HI
/!,50I 2 B"=!A 5!0,B"G! B- B$,B -F 3<#MNMCOPNQCO'&R% "/8"7,B"/3 B$! -EB"=,0 7-=E-/!/BA
B- ,7B"G,B! $"3$!5 !/!53!B"7 -F E$-B-!L7"B!8 7,55"!5C "B$ B$! !G"8!/B !/$,/7!=!/B -F
B$! 7$,53! A!E,5,B"-/ ,/8 E5-0-/3!8 0"F!B"=!% ,/ !/$,/7!8 E$-B-7(55!/B "A 3!/!5,B!8
-G!5 B$! =-8"F"!8 3<#MNW P6"3(5! )&&RC )E!7"F"7,00I% B$! ?(,/B(= !FF"7"!/7I -F B$!
(/"?(! 3<#MNMCOPKQCO'QCOR A(AE!/A"-/ "/ E(5! D,B!5 5!,7$!A B- &QC[\ ,B W2Q /=% ,/8
2CO\ ,/8 QCMM\ ,B 0-/3!5 G"A"H0! 0"3$B D,G!0!/3B$A -F O2Q ,/8 OaQ /= P6"3(5! M7R%
5!AE!7B"G!0IC U"=! 7-(5A! -F '2 E5-8(7B"-/ "/ E(5! D,B!5 A$-DA /- /-B"7!,H0!
8!75!,A! 8(5"/3 B$! MQ<$-(5 B!AB% "/8"7,B"/3 , 5-H(AB AB,H"0"BI "/ A(AB,"/,H0!
E$-B-5!8-L 5!,7B"-/A P6"3(5! MHRC U$(A% B$! B!55,7!Ae"/B!5F,7!A B$,B ,77-==-8,B!
AB,H0! l=-/-=!5<K'm D"00 A"3/"F"7,/B0I E5-B!7B B$! "/B!5F,7! F5-= '2K2 E-"A-/"/3C
4-5! "=E-5B,/B0I% B$! -G!5,00 E$-B-7,B,0IB"7 D,B!5<AE0"BB"/3 ,7B"G"BI -F
3<#MNMCOPKQCO'QCOR "A A(E!5"-5 B- =-AB -F E$-B-7,B,0IABA% (/8!5 7-/8"B"-/A -F E(5!
D,B!5 D"B$-(B ,/I A,75"F"7",0 5!,3!/BA PU,H0! )2RC
[
P,R
PHR
QC&2
QCQa
QCQW
QCQQ
O
W
M
2
&
Q
3<#MNMCOPNQCO'&R
3<#MNMCOPKQCO QCOR
VWXCX (=-0e$e3
'
[XC2 (=-0e$e3
<QCa <QCW
QCQ
QCW
QCa
&C2
&AB 2/8 M58 WB$ OB$
#I70! /(=H!5
_-B!/B",0 e f GA C Ph';R
&[
&2
a
&2Q
VQ
P7R
P8R
&CQ
QCa
QC[
QCW
QC2
QCQ
QCM
[Q
MQ
QC2
QC&
QCQ
QCQMO
QCQXQ
PfR
QC&QO
f
-7
W
3<#MNMCOPNQCO'&R
3<#MNMCOPKQCO QCOR
'
Q
MQQ
WQQ
OQQ
[QQ
XQQ
2WQ
WaQ
X2Q
V[Q
,G!0!/3B$P/=R
U"=! PAR
)

Journal of Materials Chemistry A
Page 12 of 21
View Article Online
DOI: 10.1039/C9TA05142B
I0,.)" =C P,R 4-BB<)7$-BBJI E0-BAC PHR UIE"7,0 B"=! 7-(5A! -F '2 ,/8 K2 E5-8(7B"-/A F5-=
D,B!5 AE0"BB"/3 (/8!5 0"3$B "55,8",B"-/ PvgMQQ /=R HI 3<#MNMCOPNQCO'&R ,/8 3<#MNMCOPKQCO'QCOR
E$-B-7,B,0IAB PMQ =3RC P7R _$-B-7,B,0IB"7 ?(,/B(= !FF"7"!/7IC P8R U5,/A"!/B K#fc
=!,A(5!=!/B ,/8 "/A!B A$-DA B$! ,G!5,3! 0"F!B"=!A -F B$! E$-B-3!/!5,B!8 7,55"!5A Pw/R
-HB,"/!8 F5-= B$! K#fc =!,A(5!=!/BC
H"("2/0-0/+ &!$ !"2"''0/+ 1 ) 3) $.20!, DF &!$ BF 0! /*" 3)"'"!2" 1 DFBF
dB "A -F /-B! B$,B B$! K2 !G-0(B"-/ 5,B! -F 3<#MNMCOPKQCO'QCOR D,A A-=!D$,B F0(7B(,/B "/
B$! E(5! D,B!5 ,/8 !L$"H"B!8 G,5",B"-/ F5-= H,B7$ B- H,B7$ Pt V Y=-0 $<&3<&R (/8!5
,H-G! AB,/8,58 =!,A(5!=!/B 7-/8"B"-/AC d/ B$! F"5AB $-(5% B$! 5,B! "A (E B- V Y=-0 $<&
3<& ,/8 35,8(,00I 5!8(7!A B- Za% ZM% Z[% ZW ,/8 ZX Y=-0 $<& 3<&C U$! BIE"7,0 q# A"3/,0
-F '2 ,/8 K2 I"!08 F-5 3<#MNW =,B!5",0A "/ E(5! D,B!5 D!5! A$-D/ "/ 6"3(5! )VC
A77-58"/30I% "B ,EE!,5A B$,B F-5 E$-B-7,B,0IABA% B$"A B5-(H0!A-=! E5-H0!= $,A H!!/
-HA!5G!8 !LE!5"=!/B,00I "/ K ) AIAB!=AC2V K/! -F B$! 5!,A-/A "A D"8!0I 5!3,58!8 ,A
B$! 8"FF"7(0BI F5-= -LI3!/<!G-0G"/3 5!,7B"-/ PK;hRCMQ%M& A/8 B$! 7-=E!B"B"G!
=!7$,/"A= 7,(A!8 HI '2K2 E5-8(7B"-/ "A ,/-B$!5 "=E-5B,/B 5!,A-/C U$! E5!A!/7! -F
$I85-3!/ E!5-L"8! D,A !L,="/!8 "/ 6"3(5! W, PA!! 8!B,"0A "/ )(EE-5B"/3 d/F-5=,B"-/RC
"B$ -<B-0"8"/! ,A , AE!7",0 E!5-L"8! "/8"7,B-5% B$! ,HA-5EB"-/ ,B WMa /= "/8"7,B!A B$!
J"/!B"7,0 7-=E!B"B"-/ -F BD-<!0!7B5-/ D,B!5 -L"8,B"-/ B- F-5= '2K2C U$! 5!0!,A! -F '2
A!!=A B- 0!,G! A,=! ,=-(/B -F '2K2 "/ B$! E5-7!AA -F D,B!5 AE0"BB"/3% H(B G!5I 0"BB0! K2
"A 5!0!,A!8 "/ B$! 0"3$B 5,8",B"-/C A0A-% ,FB!5 B$! AB,/8,58 7-/8"B"-/A F-5 -G!5,00 D,B!5
AE0"BB"/3 "/ E(5! D,B!5% B$! K2 5!0!,A! "A -HA!5G!8 "/ B$! 8,5J ,FB!5 B$! E5-7!8(5!A -F
G,7((="/3 B$! 3,A!A P'2 ,/8 K2R "/AB,/B0IC U$! E(5E0! 7(5G! "/ 6"3(5! WH 5!E5!A!/BA
B$! K2 5!0!,A!8 HI B$! 8!7-=E-A"B"-/ -F '2K2 "/ B$! E(5! D,B!5 AE0"BB"/3C U$!5! "A /-B
=(7$ K2 8(! B- B$! /!D 8"A7-G!5,H0! 5!,A-/ B$,B K2 8!B!7B"-/ HI , 3,A 7$5-=,B-35,E$
Pq#R !?("EE!8 D"B$ , B$!5=,0 7-/8(7B"-/ 8!B!7B-5 "A /-B ,A A!/A"B"G! ,A '2% ,/8 B$!
G,7((= -E!5,B"-/ ,0A- !LB5,7BA =-AB K2C AA , 5!F!5!/7! !LE!5"=!/B% B$! J!5=!A"/(A
E-"3/,/B 7(5G! 5!E5!A!/BA B$,B , 0,53! ,=-(/B -F K2 "/AB,/B0I 5!0!,A! F5-= ,/
,8A7"B"-(A ,?(!-(A '2K2 A-0(B"-/ D"B$-(B 0"3$B ,/8 7,B,0IABC )-% "/ B$! E5!A!/7! -F
'2K2% A-0G!/B !LB5,7B"-/ (A"/3 3,A 7$5-=,B-35,E$ Pq#R B,J!A -(B , 0-B -F K2 ,/8
!LE0,"/A B$! 0-D!5 K2 !G-0(B"-/ 5,B! !L,="/!8 "/ 6"3(5! )VC

Page 13 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B

Journal of Materials Chemistry A
Page 14 of 21
View Article Online
DOI: 10.1039/C9TA05142B

Page 15 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
0"3$B -5 8,5J "/ B$! E5!A!/7! -F '2K2C
&%W<E-A"B"-/A -F B$! =!0!= (/"B 5!8(7!A K2 ,/8 75!,B!A , A(5F,7!<,AA-7",B!8 A(E!5-L-
5,8"7,0 P)7$!=! 28RC h,E"80I% ,/-B$!5 !< ,B B$! E,5, E-A"B"-/ 5!8(7!A B$! A(E!5-L-
5,8"7,0 ,/8 E5-8(7!A , A(5F,7!<AB,H"0"T!8 "/B!5=!8",B!% &%W<!/8-E!5-L"8!% D$"7$ "A
A(HA!?(!/B0I 7-/G!5B!8 "/B- '2K2C AA , 7-=E!B"B"-/ B- '2 E5-8(7B"-/% 3!/!5,B!8 B-L"7
-LI3!/ AE!7"!A "A E,5,A"B"7 ,77-=E,/I"/3 E$-B-5!8(7B"-/ F5-= K2 B- '2K2 ,/8 "A
B$!5!F-5! B$! =-5! A!5"-(A 7$,00!/3! F-5 B$! (/AB,H0! 8!F!7BAC U$!5!F-5!% B$! 5!,A-/A -F
E--5 '2 3!/!5,B"-/ E!5F-5=,/7! ,77-=E,/"!8 HI N2 3,A !G-0(B"-/ "/ E$-B-7,B,0IB"7
E5-7!AA -F <N'2 F!,B(5!8 3<#N =,B!5",0A 7-(08 H! 0!3"B"=,B!0I "/F!55!8C c(! B-
l<N'2m 8-="/,/B 8!F!7BA "/ 3<#N =,B!5",0A% B$! 0-D '2 E5-8(7B"-/ A$-D/ "/ )V D,A
B$! 5!A(0B -F B$! F"!57! E$-B-5!8(7B"-/ E5-7!AA!A -77(55!8 "/ )(EE-5B"/3 d/F-5=,B"-/
)M% !?(,B"-/ W<aC U$(A% '2K2 3!/!5,B!8 "/ 6"3(5! W, G", E$-B-!L7"B!8 $-0!A P&CV !fR "/
fS "A 5(0!8 -(B A!?(,B"-/ VECMW U$"A =!,/A B$,B B$! 70,AA"7,0 7-/F"3(5,B"-/A -F l<N'2m
8-="/,/B ,B B$! A(5F,7! -F =!A-E-5!A ,5! /-B A("B,H0! F-5 K ) 70!,50IC
6-5 3<#MNMCOPKQCO'QCOR% B$! l=-/-=!5<K'm A$"!08 B$! E-0I=!5 B- 0"="B B-L"7"BI -F
-LI3!/ AE!7"!A ,/8 B$! AB5-/3 -L"8"T"/3 !L7"B!8 $-0!ACMO U$! !=E0-I!8
3<#MNMCOPKQCO'QCOR A$-D!8 $"3$0I A!0!7B"G! ,/8 A!/A"B"G! ,7B"G"BI -F '2 E5-8(7B"-/
PVWXCX Y=-0 $<& 3<&RC U$! l<K'm 7,/ ,0B!5 B$! A(5F,7! 7$!="AB5I HI E5-G"8"/3 ,7"8 A"B!A
-/ -5"3"/,0 H,A"7 A(5F,7! ,/8 $!/7! ,FF!7B "BA 7,B,0IB"7 '2 E!5F-5=,/7!% D$"7$ "A
7!5B,"/0I !G"8!/7!8 HI B$! G,0(!8<,88!8 !0!7B5-/ E,5,=,3/!B"7 5!A-/,/7! P;_hR
AE!7B5,C #-=E,5!8 B- 3<#MNMCOPNQCO'&R% B$! /!-B!5"7 ;)h AE!7B5, -F 3<#MNMCOPKQCO'QCOR
"/ B$! 0"3$B ,/8 8,5J ,5! 35!,B0I !/$,/7!8% B$(A "/8"7,B"/3 B$! !FF"7"!/B 3!/!5,B"-/ -F
E$-B-3!/!5,B!8 E,"5A -77(55!8 "/ B$! A(5F,7! -F l=!0!=<K'm P6"3(5! W!RC 4-5!
E5-F-(/80I% ,/ !LB5!=!0I ,7B"G,B!8 ;_h A"3/,0 D,A F"5AB0I -HA!5G!8 D$!/
3<#MNMCOPKQCO'QCOR D!5! "55,8",B!8 D"B$ 0"3$B "/ B$! E5!A!/7! -F '2K2% "/8"7,B"/3
E5-F"B,H0! E$-B-<3!/!5,B!8 5,8"7,0 E,"5A ,7B"G,B!8 "/ A!0!7B"G!0I 0"3$B<"/8(7!8 '2
E5-8(7B"-/ P6"3(5! WFRC U$(A% H,A!8 -/ B$! A(E!5"-5 '2 E!5F-5=,/7!% , H!/"3/
E$-B-7,B,0IB"7 ,7B"G"BI 7,/ H! !/G"A,3!8 -/ B$! 7-/A"8!5,B"-/ -F '2K2C #-=E,5!8 B-
H(0J 3<#N% B$! "/75!,A!8 A(5F,7!A ,5!, ,/8 B-=,B-"8 E-5!A B$,B 0,I E0!/B"F(0 H,5!
#

Journal of Materials Chemistry A
Page 16 of 21
View Article Online
DOI: 10.1039/C9TA05142B
"/B!5F,7!A -F l=!0!=<K'm 7-(08 (0B"=,B!0I H! !=E0-I!8 ,A ,7B"G! A"B!AC A/8 B$!
AB,H0!l<K'm 35-(EA A$-D B$! ,/B"<B-L"7 !FF!7B "/ , AB5-/3 -L"8"T"/3 !/G"5-/=!/BC U$!
AI/!53"AB"7 "/B!5E0,I H!BD!!/ ,7B"G! F5,7B"-/A ,/8 AB,H0! 7-=E-/!/BA !/$,/7! B$!
A!0!7B"G"BI ,/8 !/!53!B"7A F-5 '2 !G-0(B"-/C "B$ B$! 8"A,EE!,5,/7! -F 8!F!7BA "/
3<#MNMCOPNQCO'&R% B$! ,7B"G"BI F-5 'u -G!5 K2 E$-B-5!8(7B"-/ "/ B$! #S 7-=E!B"/3
E5-7!AA!A H--AB!8 E5!F!5!/B",0 '2 !G-0(B"-/ PVWXCX Y=-0 $<& 3<&R "/ B$! 0"3$B P)M%
!?(,B"-/ W<aRC "B$ , 0-B -F '2 8!B!7B!8 HI q# !?("E=!/B% B$! ,H(/8,/B '2K2
5!,A-/,H0I 7-=!A F5-= E$-B-!L7"B!8 $-0!A "/ fS P2C& !fR P6"3(5! W,RC U$! '2K2 "/
B$! 7,A! -F B$! A(5F,7!<7$,/3!8 3<#MNMCOPKQCO'QCOR 5!3(0,B!A B$! -L"8,B"-/ E,B$% D$"7$
A$-DA BD- A-(3$B<,FB!5 5-0!A "/ E$-B-7,55"!5 A!E,5,B"-/eB5,/AE-5B =!7$,/"A= "/
)7$!=! 2> K2 ,/8 $-0!A A7,G!/3"/3 !FF!7BC d/ B$! 0"3$B% B$! J"/!B"7,00I F,G-5!8 E5-7!AA
G", BD-<!0!7B5-/ E,B$D,I A(E!5"-50I B- F-5= '2K2 F,AB 7,EB(5!8 B$! !L7"B!8 $-0!A "/
B$! fSC d/ B$! "/F!5"-5 E-A"B"-/% B$! K2 3!/!5,B"-/ D,A A(EE5!AA!8 ,/8 0-AB B$! 7$,/7!
B- E,5B"7"E,B! "/ B$! E$-B-5!8(7B"-/ E5-7!AA "/ #S P)M% !?(,B"-/ O<aRC U$(A% '2K2
F-5=,B"-/ "/ B$! 0"3$B ,A , H!/"3/ $-0! A,75"F"7! !FF!7B B$,B E5-E!0A $-0!A F,AB
A!0F<E(=E"/3C U$! =-B"G,B"-/ -F E$-B-7,55"!5 A!E,5,B"-/eB5,/AE-5B "/75!,A!8 B$! 0"F!
B"=! -F F5!! 7$,53! -/ ,7B"G! A"B!A B- E5-=-B! '2 E5-8(7B"-/C $!/ '2 E5-8(7B"-/
AB-EE!8 "/ B$! 8,5J% '2K2 ,A ,/ lK2 7,55"!5m =,"/0I 5!0!,A!8 E0!/BI -F K2 "/ B$! 8,5J
P6"3(5! W,RC d/ B$! 7I70!% B$! B!AB "=E0!=!/B!8 -G!5,00 D,B!5 AE0"BB"/3> 2'2K n '2 u
'2K2 P0"3$B 5!,7B"-/R^ '2K2 n &e2'2KuK2 P8,5J 5!,7B"-/RC d/ 3!/!5,0% -(5 5!A(0BA 0!,8
(A B- ,53(! B$,B D$,B "A /!!8!8 "/ B$! A-0,5 D,B!5 AE0"BB"/3 "A -/0I B$! 8!=,/8 '2
E5-8(7B "/AB!,8C )- B$! -/!<8!=,/8 '2 3!/!5,B"-/ AIAB!=A (A"/3 B$! A(/ ,A , A-(57! -F
!/!53I E5!A!/B /!B 5!A(0B "/ B$! 0"3$B A$-D/ "/ )7$!=! 2> 2'2K n '2u '2K2C
< !2(.'0 !'
S,A!8 -/ B$! A7$!=,B"7,0 "8!, B- E5!F!5!/B",00I 0"H!5,B! =-5! ,7B"G! B!55,7!Ae"/B!5F,7!A
P=!0!=R ,/8 F"L B$! (/AB,H0! 8!F!7BA P<N'2R B- 5!A"AB B-L"7"BI ,/8 A(EE5!AA B$!
E$-B-7,55"!5 5!7-=H"/,B"-/% D! 8!G!0-E!8 B$! A(5F,7! l=!0!=<K'm 8-="/,/B
3<#MNMCOPKQCO'QCOR F-5 A"=(0B,/!-(A0I "/75!,A"/3 ,7B"G"BI F-5 A-0,5 !/!53I 7-/G!5A"-/
,/8 8!F!/8"/3 B$! A(5F,7! F5-= B$! B$5!,BA -F '2K2 !L"AB!/7!C "B$ B$! B5,/AF-5=,B"-/
$

Page 17 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
-F 7,B,0IB"7 =,B!5",0A P=-/-=!5<N'2 H,A!8 3<#MNMCOPNQCO'&R B- =-/-=!5<K' H,A!8
3<#MNMCOPKQCO'QCOR% , H!/7$=,5J"/3 '2<!G-0G"/3 5,B! F-5 B$! A(5F,7! $I85-LI0,B!8
3<#MNMCOPKQCO'QCOR E$-B-7,B,0IAB (/8!5 G"A"H0! 0"3$B Pk MQQ /=R "55,8",B"-/ (E B- VWXCX
Y=-0 $<&3<& D,A ,7$"!G!8% ,H-(B &W B"=!A !/$,/7!=!/B "/ 7-=E,5"A-/ D"B$ B$,B -F
3<#MNWC U$! ?(,/B(= !FF"7"!/7I -F 3<#MNMCOPKQCO'QCOR A(AE!/A"-/ "/ E(5! D,B!5
5!,7$!A B- &QC[\ ,B W2Q /= ,/8 2CO\ ,B , 0-/3!5 G"A"H0! 0"3$B D,G!0!/3B$ -F O2Q /=C
6(5B$!5=-5!% B$! A!0!7B"G"BI ,/8 /!7!AA"BI H!BD!!/ 3<#MNMCOPNQCO'&R ,/8
3<#MNMCOPKQCO'QCOR F-5 E5-8(7"/3 '2 ,/8 K2 "/ B$! E5!A!/7! -F '2K2 ,5! E5!A!/B!8C
d/AE"5!8 HI /,B(5,0 E$-B-AI/B$!A"A% B$! B!5=!8 0"3$B 5!,7B"-/ P2'2K n '2 u '2K2R ,/8
8,5J 5!,7B"-/ P'2K2 n &e2'2K u K2R "=E0!=!/B!8 -G!5,00 D,B!5 AE0"BB"/3 $,G! H!!/
8!E"7B!8 !LE!5"=!/B,00I ,/8 A7$!=,B"7,00IC 4-AB "=E-5B,/B0I% B$"A A7$!=! -F
E$-B-AI/B$!B"7 '2 F5-= E(5! D,B!5 /-B -/0I B,7BF(00I A"8!AB!EA K2 5!0!,A! "AA(!A ,/8
E5!F!5!/B",00I =,L"="T!A B$! 7-5! G,0(! -F '2% H(B -G!5<A"=E0"F"!A B$! A"=E0!AB
D,B!5<AE0"BB"/3 D,IC 6"/,00I% D! F"5AB ,53(! B$,B% D"B$ B$! 7$,/3! "/ F-7(A -/
-/!<8!=,/8 A-0,5 '2 AIAB!= F-5 E(5! D,B!5 AE0"BB"/3% "B B$(A D"00 -EB"="T! B$! '2
E5-8(7B"-/ "/ B$! 8!G!0-E=!/B -F A-0,5 D,B!5 AE0"BB"/3 E0,/BAC
KN3")0%"!/&( '"2/0 !
;*")%&(#2 !O.,&/" 3.)" ,#<=>M 0! '/"3 G? S,A"7,00I% ,A A$-D/ "/ AB!E &% =!0,="/!
P#MNMR F"5AB0I F-5=A =!0,= P#[NX% =!0,="/! 8"=!5R H!F-5! MOQ C AH-G! MOQ % B$!
"/B!57-/G!5A"-/ -F "/"B",0 $!EB,T"/!<H,A!8 =-/-=!5 =!0!= P#[NXR "A F-5=!8C U$!/% B$!
-0"3-=!5A ,5! 8-="/,B!8 HI o]o "/B!5,7B"-/A H!BD!!/ B$!A! 8"A7<A$,E!8 =-0!7(0!A% ,/8
AB,7J!8 "/B!50,="/,50I HI f,/ c!5 ,,0A 85"G"/3 F-57! D$!/ $!,B!8 F(5B$!5C 4!0-/
PE-0I=!5"7 7,5H-/ /"B5"8!% P#[NXR "A F-5=!8 ,A B$! B!=E!5,B(5! 5,"A!8 F(5B$!5 B- OQQ %
D$"7$ "A B$!5=,00I AB,H0! (E B- B!=E!5,B(5!A -F [OQ C '"3$ B!=E!5,B(5! POOQ R D,A
A!B $!5! B- 85"G! =!0-/ 7-/8!/A,B"-/ , AB!E F(5B$!5 B- F-5= , 2c !LB!/8!8 /!BD-5JCM[
,#<=>=?@A>C?@DGE 40/* /")%0!&( 1) !/0")' 1 .50P.0/ .' >DF ,) .3' 5+ 3 )"'
"!,0!"")0!, 0! '/"3 F? d/ AB!E 2% E-0I=!5"7 =!0-/ 3-!A B$5-(3$ ,/-B$!5 B$!5=,0
E-0I=!5"T,B"-/ E5-7!AA% ,/8 B$! E5-8(7BA "/ AB!E & 7-/B,"/ , 7!5B,"/ =-/-=!5A ,/8
-0"3-=!5A D$"7$ /!!8 F(5B$!5 B$!5=,0 B5!,B=!/B ,A A0-D0I ,A E-AA"H0! B- 5!,0"T! F(00I
%

Journal of Materials Chemistry A
Page 18 of 21
View Article Online
DOI: 10.1039/C9TA05142B
E-0I=!5"T,B"-/ -5 !0"="/,B"-/ (/AB,H0! #<7-/B,"/"/3 ,/8 N<7-/B,"/"/3 ,88(7BAC d/ B$"A
E5-7!AA% -/ B$! H,A"A -F B5",/3(0,5 $-0!A F-5=!8 2c 0"/J"/3 ,55,/3!=!/B% , 0,53! /(=H!5
-F E-5!A D$"7$ !LE-A! B!5="/,0 F5-/B"!5A D"B$ (H"?("B-(A N'2 35-(EA ,B B$! A(5F,7! ,5!
F-5=!8CMX
;*" 2 !-")'0 ! %"2*&!0'% 1 ,#<=>=?@ABC?@DC?@E /")%0!&( ,) .3' 1) % #>DF / #BD
0! '/"3 =? U$! $I85-0IA"A E5-7!AA!A D,A "/G-0G!8 "/ H-"0"/3 8"0(B! /"B5"7 ,7"8 ,B &OQ y#
F-5 2 $ B- E5-8(7! 3<#MNMCOPKQCO'QCOR P)(EE-5B"/3 d/F-5=,B"-/ )&% )B!E MRC 6"5AB% ,="/-
35-(EA -/ ,/ A<B5",T"/! 5"/3 (/8!53- E5-B-/,B"-/ (/8!5 ,7"8"7 7-/8"B"-/AC U$! F"5AB
E5-B-/,B"-/% B- "/75!,A! B$! 0!,G"/3 ,/8 !0!7B5-E$"0"7 B!/8!/7I -F B$! "="/!A% =-B"G,B!
B$! /!LB AB!E B$,B D,B!5 ,BB,7JA B$! "="/! 7,5H-/ !LE!8"!/B0I% B$"A "A , G!5I "=E-5B,/B
AB!EC 6(5B$!5% B$! !LB5(8!8 ,="/! =-0!7(0!A ,5! /!(B5,0"T!8 HI B$! ,7"8% ,/8 B$!
7-/G!5A"-/ =!7$,/"A= "A E5-=-B!8C d/ A(==,5I% H-"0"/3 8"0(B! /"B5"7 ,7"8 $I85-0IT!A
B$! ,="/- 35-(EA -F =!0,="/! "/ , AB!ED"A! =,//!5 A(77!AA"G!0ICMa
<*&)&2/")0Q&/0 !? U5,/A="AA"-/ !0!7B5-/ ="75-A7-EI PU;4R% '"3$<5!A-0(B"-/
B5,/A="AA"-/ !0!7B5-/ ="75-A7-EI P'hU;4R ,/8 !/!53I 8"AE!5A"G! *<5,I AE!7B5, P;c)R
,/,0IA"A D!5! E!5F-5=!8 -/ , z;4<2&QQ6 ="75-A7-E! ,B ,/ ,77!0!5,B"-/ G-0B,3! -F 2QQ
JfC U$! *hc E,BB!5/A D!5! E!5F-5=!8 -/ _$"0"EA *{_!5B _5- )(E!5 *<5,I
8"FF5,7B-=!B!5 D"B$ #( b| 5,8",B"-/C S5(/,(!5<;==!BB<U!00!5 PS;UR A(5F,7! ,5!,
=!,A(5!=!/BA D,A E!5F-5=!8 D"B$ , 4"75-=!5"B"7A U5"AB,5 dd MQ2Q4 /"B5-3!/
,8A-5EB"-/ ,EE,5,B(AC U$! sf<G"A AE!7B5, Pch)R D!5! 5!7-58!8 -/ , )$"=,8T(
csf<MXQQ AE!7B5-E$-B-=!B!5C U$! 6-(5"!5 B5,/AF-5= "/F5,5!8 P6U<dhR AE!7B5, D!5!
=!,A(5!8 -/ , 4,3/,<dhXOQ 6Udh AE!7B5-=!B!5 "/ , bS5 E!00!B% A7,//"/3 F5-= WQQQ B-
WQQ 7=<& ,B 5--= B!=E!5,B(5!C _$-B-0(="/!A7!/7! P_1R =!,A(5!=!/BA D!5! 5!7-58!8
D"B$ ,/ !L7"B,B"-/ D,G!0!/3B$ -F M[Q /=C *<5,I E$-B-!0!7B5-/ AE!7B5, P*_)R D!5!
,7?("5!8 -/ ,/ ;)#A1AS 4bdd D"B$ 43 b| P$} r &2OMC[ !fR ,A B$! !L7"B,B"-/ A-(57!C
U$! H"/8"/3 !/!53"!A -HB,"/!8 "/ B$! *_) AE!7B5,0 ,/,0IA"A D!5! 7-55!7B!8 F-5 AE!7"=!/
7$,53"/3 HI 5!F!5!/7"/3 # &A B- 2aWCO !fC U$! G,0!/7! H,/8 *<5,I E$-B-!0!7B5-/
AE!7B5, PfS*_)R D!5! =!,A(5!8 D"B$ =-/-7$5-=,B"T!8 A0 b| *<5,I 5,8",B"-/C
h--=<B!=E!5,B(5! ;)h AE!7B5, D!5! -HB,"/!8 (A"/3 , z;K1 z;)<6A2QQ ;)h
AE!7B5-=!B!5 PMQQ b% VCQ[M q'T% *<H,/8RC
&

Page 19 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
A2R! 4("$,"%"!/'
U$"A D-5J D,A A(EE-5B!8 HI B$! N,B"-/,0 N,B(5,0 )7"!/7! 6-(/8,B"-/ -F #$"/, Pq5,/BA
N-C &&aXO2OX% 2&[QM2QX% &&[QO2QW ,/8 s&OM22[OR% ,/8 B$! 6(/8,=!/B,0 h!A!,57$
6(/8A F-5 B$! #!/B5,0 s/"G!5A"B"!A P b2M&QQQQQXQRC
H.33 )/0!, 8!1 )%&/0 !
U$! )(EE-5B"/3 d/F-5=,B"-/ "A ,G,"0,H0! F5!! -F 7$,53! -/ B$! A#) _(H0"7,B"-/A
D!HA"B! ,B cKd>*****C
A88"B"-/,0 8,B, ,/8 =!B$-8A^ 6"3(5!A )&])&2^ U,H0!A )&% )2^ )(EE-5B"/3 5!F!5!/7!A
P_c6R
:"1")"!2"'
&
2
M
AC b(8- ,/8 .C 4"A!J"% 8*3B@ '$)@ ,32@% 2QQV% =S% 2OM]2XaC
*C #$!/% )C )$!/% 1C q(- ,/8 )C )C 4,-% 8*3B@ ,32@% 2Q&Q% GGC% [OQM][OXQC
'C ,/3% 1C +$,/3% +C #$!/% zC '(% )C 1"% +C ,/3% zC 1"( ,/8 *C ,/3%
8*3B@ '$)@ ,32@% 2Q&W% M=% O2MW]O2WWC
W
zC 1"% C #("% .C )(/% .C #$(% C #!/ ,/8 6C c-/3% J@ F!"3+@ 8*3B@ A% 2Q&X%
@% VMOa]VM[WC
O
[
X
UC '"A,B-="% zC b(H-B, ,/8 bC c-=!/% 8*3B@ '$)@ ,32@% 2Q&W% M=% XO2Q]XOMOC
.C *(% 4C b5,FB ,/8 hC *(% 8*3B@ '$)@ ,32@% 2Q&[% M@% MQMV]MQO2C
zC 1"% +C +$,/3% C #("% 'C ,/3% C #!/% qC z-$/A-/% qC z",/3% )C +$,/3 ,/8
6C c-/3% A8' 8!"!&@% 2Q&a% S% aMX[]aMaOC
a
V
_C #$!/% 'C ,/3% 'C 1"(% +C N"% zC 1"% .C +$-( ,/8 6C c-/3% AKK&@ 8!"!&@ L
D%2#+$%@% 2Q&V% FMF% &V]MQC
4C b,T($"J-% J@ ?*$"$)*3B@ ?*$"$/#$&@ 8 ?*$"$)*3B@ ,32@% 2Q&&% GF% 2MX]
2[aC
&Q
&&
)C #$!/% UC U,J,B, ,/8 bC c-=!/% !"@ ,32@ F!"3+@% 2Q&X% F% &XQOQC
bC c-=!/% )C N,"B-% 4C )-=,% UC K/"A$" ,/8 bC U,=,5(% J@ 8*3B@ '$)@ 8*3B@
8$BB>%@% &VaQ% OWM]OWWC
'

Journal of Materials Chemistry A
Page 20 of 21
View Article Online
DOI: 10.1039/C9TA05142B
&2
hC AH!% bC ),I,=,% bC c-=!/ ,/8 'C A5,J,D,% 8*3B@ ?*(4@ .3""@% 2QQ&% =MM%
MMV]MWWC
&M
&W
A00!/ zCS,58% J@ ?*$"$)*3B@% &VXV% GC% OV]XOC
zC U,/3% zC hC c(55,/B ,/8 cC hC b0(3% J@ AB@ 8*3B@ '$)@% 2QQa% G=C% &MaaO]
&MaV&C
&O
&[
&X
&a
&V
2Q
2&
zC _C U-5!00,% #C zC q,30",58"% zC )C #$!/% cC bC S!8",J-% SC #-0~/% zC #C ,I% _C
AC )"0G!5 ,/8 cC qC N-7!5,% ?+$)@ !"&@ A)!-@ ')#@% 2Q&O% GGF% 2MMX]2MW2C
zC 1"(% .C 1"(% NC 1"(% .C ',/% *C +$,/3% 'C '(,/3% .C 1"FA$"BT% )C UC 1!!% zC
+$-/3 ,/8 +C b,/3% ')#3%)3% 2Q&O% =MT% VXQ]VXWC
)C<UC .-/3% .C 'C N3% )C<_C #$,"% 1C<1C U,/ ,/8 C<zC K/3% 8*3B@ ,32@% 2Q&[%
GGU% X&OV]XM2VC
qC +$,/3% +C AC 1,/% 1C 1"/% )C 1"/ ,/8 *C ,/3% 8*3B@ ')#@% 2Q&[% T% MQ[2]
MQ[[C
bC 4,!8,% *C ,/3% .C N"A$"$,5,% cC 1(% 4C A/B-/"!BB" ,/8 bC c-=!/% J@
?*(4@ 8*3B@ 8% 2QQV% GG=% WVWQ]WVWXC
fC C 'C 1,(% 4C SC 4!A7$% fC c(EE!0% fC S0(=% zC )!/J!5 ,/8 SC fC 1-BA7$%
J@ AB@ 8*3B@ '$)@% 2Q&O% G=T% &Q[W]&QX2C
zC ;$5=,"!5% UC NC fC b,5A"0"% AC 1C )-H-0!DAJ" ,/8 C c-=7J!% J@ ?*(4@
8*3B@ A% 2Q&X% GFG% WXOW]WX[WC
22
2M
1C 1"/% 'C K(% .C +$,/3 ,/8 *C ,/3% A8' 8!"!&@% 2Q&[% U% MV2&]MVM&C
#C 4!5A7$`,//% UC UIH-5AJ"% )C K5B$=,//% 6C .,/3% bC )7$D,5TH(53% 4C
1(H0-D% 4C #C 1(L<)B!"/!5 ,/8 UC )7$!8!0<N"!85"3% ?*(4@ ,32@ L% 2Q&M% ST%
2QO2QWC
2W
2O
2[
2X
qC 'C 4--/% 4C 6(`"BA(J,% )C b"=% UC 4,`"=,% *C ,/3 ,/8 C #$-"% A8'
8!"!&@% 2Q&X% T% 2aa[]2aVOC
.C +$!/3% .C z",-% .C +$(% 1C 'C 1"% .C ',/% .C #$!/% AC c(% 4C z,5-/"!7 ,/8
)C +C 9",-% !"@ 8$BB>%@% 2Q&W% @% WXaMC
cC zC 4,5B"/% bC 9"(% )C AC )$!G0"/% AC cC ',/8-J-% *C #$!/% +C q(- ,/8 zC
U,/3% A%73E@ 8*3B@ M%"@ D-@% 2Q&W% @=% V2WQ]V2WOC
cC +$!/3% *C NC #,- ,/8 *C ,/3% A%73E@ 8*3B@ M%"@ D-@% 2Q&[% @@% &&O&2]
(

Page 21 of 21
Journal of Materials Chemistry A
View Article Online
DOI: 10.1039/C9TA05142B
&&O&[C
2a
2V
MQ
M&
M2
C #$!% C #$!/3% UC .,-% 6C U,/3% C 1"(% 'C )(% .C '(,/3% 9C 1"(% zC 1"(%
6C '(% +C _,/% +C )(/ ,/8 )C !"% J@ AB@ 8*3B@ '$)@% 2Q&X% G=V% MQ2&]MQ2[C
)C N,G,0-/% AC c$,JA$"/,=--5B$I% 4C A0G,5-% 4C A/B-/"!BB" ,/8 'C q,57Ä,%
8*3B@ '$)@ ,32@% 2Q&X% MU% WOQ&]WO2VC
)C C b-$0% 1C !"/!5% 1C )7$D,5BAH(58% 1C b-/AB,/B"/-GAJ"% 1C zC C )$"=-/%
.C S!/ c,G"8% 4C AC d5-/ ,/8 cC 4"0AB!"/% ')#3%)3% 2QQV% =FM% XW]XXC
zC h,/% zC +$,/3% zC .(% 4C z,5-/"!7 ,/8 )C +C 9",-% 8*3B@ '$)@ ,32@% 2Q&W% M=%
XXaX]Xa&2C
UC '"5,"% .C b-F(`"% 'C ),J,=-B-% .C )$"5,"A$"% )C U,/,J, ,/8 )C d7$"J,D,% A8'
8!"!&@% 2Q&O% @% MQOa]MQ[[C
MM
MW
zC 1"(% 'C ,/3 ,/8 4C A/B-/"!BB"% 8*3B@ '$)@ ,32@% 2Q&[% M@% 2MQa]2M2[C
'C +$,/3% 1C 'C q(-% 1C +$,-% SC ,/ ,/8 .C .,/3% J@ ?*(4@ 8*3B@ .3""@%
2Q&O% U% VOa]V[MC
MO
M[
MX
Ma
C hC #$!/3% *C +$,-% 'C )(% 6C U,/3% C #$!% 'C +$,/3 ,/8 9C 'C 1"(% !"@
D%3+7(% 2Q&V% M% &&O]&22C
SC zÅ53!/A% ;C d55,/% zC )!/J!5% _C b5-00% 'C 4Å00!5 ,/8 C )7$/"7J% J@ AB@
8*3B@ '$)@% 2QQM% GF@% &Q2aa]&QMQQC
4C cÇH0"/3!5% SC fC 1-BA7$% zC ,7J% zC U$(/% zC )!/J!5 ,/8 C )7$/"7J%
8*3B@ 8$BB>%@% 2QQV% &OW&]&OWMC
A<U5",T"/!A ,/8 c!5"G,B"G!A^ d/B!5A7"!/7!>N!D .-5J% &VOVC
!)