A yl Viologens: Unp eceden ed S abili y o Viologen-De i a i es as
Anoly es o Alkaline Redox Flow Ba e ies
Rubén Rubio-P esa,*Edga Ven osa,*and Robe o Sanz*
Ci e This: h ps://doi.o g/10.1021/acsaem.5c02255
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ACCESS Me ics & Mo e A icle Recommenda ions *
sı Suppo ing In o ma ion
ABSTRACT: Viologen de i a i es a e widely used in he anoly es o aqueous o ganic
edox low ba e ies (AORFBs). Howe e , hei applica ions ha e been es ic ed o
neu al pH sys ems due o hei as deg ada ion in basic media ia a dealkyla ion
p ocess d i en by a nucleophilic a ack o hyd oxide. In his s udy, a amily o iologen-
based anoly es sui able o alkaline sys ems is in oduced, demons a ing ha p ope ly
designed iologens can also be used in alkaline condi ions. A a ie y o N-a yl iologens
a e p epa ed and cha ac e ized, showing ha he dealkyla ion p ocess is p e en ed by
bonding an a yl g oup di ec ly o he N-a om o he bipy idine co e. Pai ing B-2,5-
DHPV o he anoly e and K4Fe(CN)6 o he ca holy e, a ull alkaline AORFB ha ing
a nominal cell ol age a 0.98 V main ains s able capaci y o e 1400 con inuous cycles
wi h nea ly 0.03%·h−1capaci y decay, which is a e y accep able alue o a iologen in
an alkaline medium. Ou esul s enable he b oadening o he ange o iable o ganic
anoly es o alkaline AORFBs.
KEYWORDS: aqueous o ganic edox low ba e ies, alkaline media, a yl iologen, chemical s abili y, molecula enginee ing
1. INTRODUCTION
De eloping la ge-scale, sa e, and cos -e ec i e ene gy s o age
sys ems is essen ial o ha ness enewable ene gy e ec i ely.
1−3
Aqueous edox low ba e ies (ARFBs) s and ou as highly
p omising candida es o s o ing ene gy om in e mi en
sou ces such as sola and wind powe due o hei non lammable
elec oly es and he abili y o independen ly scale ene gy and
powe . While anadium edox low ba e ies a e he mos ma u e
ARFBs, hey ace economic and esou ce challenges due o hei
eliance on c i ical ma e ials.
4
Aqueous o ganic edox low
ba e ies (AORFBs) ep esen a compelling al e na i e, using
di e se, cos -e ec i e, and s uc u ally unable o ganic mole-
cules.
5
Viologens a e pa icula ly a ac i e as anoly es in neu al
AORFBs o hei adequa e edox kine ics, sui able edox
po en ial, and easible syn hesis.
6,7
Viologen de i a i es
p e iously epo ed as anoly es in AORFBs exclusi ely p esen
alkyl g oups as subs i uen s o he qua e niza ion o ni ogen
a oms in he 4,4′-bipy idine co e.
8−13
Figu e 1 shows he
s uc u es o he mos ep esen a i e de i a i es desc ibed in he
li e a u e o hese applica ions.
The e o e, he ope a ing condi ions o hese ba e ies should
be s ic ly and exclusi ely nea neu al media, as iologens a e
epo ed o be uns able in alkaline media by se e al
au ho s.
14−17
Howe e , alkaline ba e y sys ems p esen
signi ican ad an ages compa ed o neu al media including
ele a ed conduc i i y, inc eased powe ou pu , he abili y o
easily add ess Fa adaic imbalance, and g ea e s abili y o pH
le el ( he pH alue luc ua es easily in neu al pH due o he
loga i hmic a io be ween pH and OH−concen a ion).
18−23
Recei ed: July 22, 2025
Re ised: Sep embe 18, 2025
Accep ed: Oc obe 27, 2025
Figu e 1. Rep esen a i e selec ion o iologen de i a i es desc ibed in
he li e a u e as anoly es o AORFBs which ope a e s ic ly and
exclusi ely in neu al/nonalkaline media.
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Despi e hese ad an ages, hese sys ems ha e been p ima ily
limi ed o he use o quinone, phenazine, o luo enone
de i a i es as anoly es o AORFBs.
24−26
The e o e, he e is
g ea in e es in de eloping o ganic elec oac i e ma e ials
sui able o alkaline sys ems o enable AORFBs o capi alize on
hese ad an ageous ea u es. In his con ex , ou esea ch g oup
has s udied he chemical s abili y o hese elec oac i e species in
alkaline media, analyzing he decomposi ion p ocess o 1,1′-bis-
3-sul ona op opyl iologen ((SP )2V), which can be conside ed
as he s a e-o - he-a de i a i e unde alkaline condi ions. I is
pos ula ed ha his deg ada ion in ol es a dealkyla ion p ocess
p omo ed by he nucleophilic a ack o he hyd oxide anion on
C(sp3) di ec ly bonded o he ni ogen a om (Scheme 1A).
Th ough molecula enginee ing, we showed ha his deg ada-
ion p ocess can be signi ican ly slowed down by inc easing he
s e ic hind ance a ound he si e suscep ible o nucleophilic
a ack (Scheme 1B).
27
Un o una ely, his s a egy does no
comple ely p e en deg ada ion bu only slows down he
p ocess unde mild alkaline condi ions (pH 9−11). As wi h
iologens, o he elec oac i e species o edox low ba e ies,
such as an h aquinones, unde go decomposi ion by nucleophilic
subs i u ion unde alkaline condi ions.
28
To mi iga e his undesi ed pa hway, which is associa ed wi h
capaci y decay, Aziz e al. add essed he p oblem o
an h aquinones by eplacing ca bon−he e oa om by ca bon−
ca bon bonds be ween edox cen e s and la e al chains,
conside ing ha C−C bonds a e mo e chemically esis an
agains nucleophilic a ack han ca bon−he e oa om bonds like
C−O (S, N).
29
Howe e , his elegan s a egy is no sui able o
iologens because he p esence o ni ogen a oms is equi ed o
he elec oac i i y o he compound as hey a e essen ial
componen s o he edox co e in he s uc u e o his amily o
elec oac i e species. Fo hese easons, a new app oach mus be
de ised i iologen de i a i es a e o be used in alkaline
AORFBs. In his wo k, we p opose a new amily o iologen-
based anoly es capable o wi hs anding s ong alkaline
condi ions due o hei inc eased chemical s abili y agains
nucleophilic a ack. In his con ex , we en isioned ha comple e
inhibi ion o he deg ada ion pa hway, based on he nucleophilic
a ack o hyd oxide anions on he C a oms bonded o he N
a oms o he bipy idinium co e, could be achie ed by changing
he elec onic na u e o hese C a oms. Thus, we p opose he
in oduc ion o a yl g oups as N-subs i uen s o comple ely
p e en he nucleophilic a ack o hyd oxide anions (Scheme
1C). Gi en he highe elec onega i i y o C(sp2), compa ed o
C(sp3), we p edic ed ha iologen decomposi ion h ough he
clea age o he C−N bond would be g ea ly dis a o ed o
C(sp2)−N bonds. Acco ding o his p oposal, a yl iologens,
de i ed om a bipy idine sca old subs i u ed wi h a yl g oups a
he N a oms, would exhibi highe s abili y unde alkaline
condi ions. I should be no ed ha he p esence o a oma ic
g oups in he iologen molecule could educe he solubili y in
aqueous media. Thus, u he modi ica ion o he s uc u e by
in oducing hyd ophilic g oups is necessa y o imp o e he
o e all pe o mance.
2. EXPERIMENTAL SECTION
2.1. Ma e ials. All common eagen s and sol en s we e pu chased
om Ald ich o Al a-Aesa and used as ecei ed wi hou u he
pu i ica ion.
2.2. NMR Measu emen s. NMR spec a we e measu ed on a
B uke A ance III HD 300 MHz spec ome e . 1H NMR: spli ing
pa e n abb e ia ions a e s, single ; d, double ; , iple ; q, qua e ; dd,
double double ; ddd, double s o double s o double s; dd , double
double o iple s; d , double o iple s; dq, double o qua e s; d,
iple o double s; qd, qua e o double s; p, pen uple ; h, sex e ; hep ,
hep e ; m, mul iple ; b, b oad; a, appa en ; he chemical shi s a e
epo ed in ppm using he esidual sol en peak as a e e ence. 13C
NMR spec a we e eco ded a 75.4 MHz using b oad-band p o on
decoupling, and chemical shi s a e epo ed in ppm using adequa e
sol en peaks as in e nal e e ence (CH3OH: 49.50), and he
mul iplici ies we e de e mined by DEPT expe imen s.
2.3. pH Measu emen . pH measu emen s we e de e mined using
an Accume AB150 de ice which allows us o eco d pH alues a
di e en imes.
2.4. Cyclic Vol amme y. Cyclic ol amme y s udies we e
pe o med using an Au olab PGSTAT12 ins umen (Me h om-
Au olab, The Ne he lands) wi h NOVA 2.1.3 so wa e. A h ee-
elec ode cell was employed using a polished glassy ca bon wo king
elec ode (Aelec ode = 7 mm2) and a P wi e coun e elec ode (99%
pu i y), and he Ag/AgCl (3 M KCl) elec ode was used as an aqueous
e e ence elec ode.
Scheme 1. (A) P oposed Deg ada ion Pa hway o Viologen-Based Anoly es. (B) Ou P e ious Wo k and Ou Ini ial Solu ion o
Imp o e he Chemical S abili y o Viologens unde Alkaline Condi ions. (C) Ou P oposal o Sol e he P oblem
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2.5. S a ic Ba e y Assembly. A s a ic cell was designed using
Ske chUp so wa e and manu ac u ed using an ul a iole (UV) liquid-
c ys al-display-based s e eoli hog aphy 3D p in e (Pho on Mono SE,
Anycubic) and a comme cial clea esin (Anycubic). A il e -p essed
s a ic cell using expanded g aphi e (SGL Ca bon), g aphi e el (SGL
Ca bon), and Na ion 212 (Ion Powe ) as he cu en collec o ,
elec ode, and ion-selec i e memb ane, espec i ely, was used. The
p ojec ed a ea o he cell was 3 cm2(in e nal olume ≈0.38 mL).
Gal anos a ic cha ge−discha ge measu emen s we e pe o med by
using a Newa e BTS ba e y es ing sys em CT-40087-5 V6A-S1. The
ba e ies we e cha ged a 5 mA·cm−2wi h ol age limi s a 1.2 V.
The ea e , he ba e ies we e discha ged a 5 mA·cm−2wi h a ol age
limi o 0.5 V. Gene al condi ions: he ba e y was illed using 2 mL o
he anoly e wi h 0.2 M iologen in 1.0 M KCl and 0.8 M KOH and 2 mL
o he ca holy e wi h 0.3 M K4Fe(CN)6in 1.0 M KCl and 0.8 M KOH.
All elec oly es we e p epa ed wi h deionized wa e , and bo h we e
pu ged wi h a gon p io o use.
2.6. Flow Ba e y Assembly. Fil e -p essed low cells using Na ion
212 and g aphi e el as he ion-selec i e memb anes and elec odes
we e used in his s udy. The p ojec ed a ea o he cell was 9 cm2. The
low a e was ixed a abou 50 mL·min−1. Gal anos a ic and
po en ios a ic (cons an cu en , ollowed by cons an ol age p o ocol
(CC−CV)) cha ge−discha ge measu emen s we e ealized using a
Newa e BTS ba e y es ing sys em CT-40087-5 V6A-S1. The ba e ies
we e cha ged a 30 mA·cm−2wi h ol age limi s a 1.2 V. The ea e , he
ba e ies we e discha ged a −30 mA·cm−2wi h a ol age limi o 0.5 V
unde A a mosphe e. Gene al condi ions: anoly e (12 mL), 0.2 M
iologen in 1.0 M KCl, and 0.8 M KOH; ca holy e (45 mL), 0.3 M
K4Fe(CN)6in 1.0 M KCl, and 0.8 M KOH.
2.7. Solubili y Tes . The solubili y o iologen B-2,5-DHPV in 1 M
KOH was de e mined by using UV− is spec opho ome y a 240 nm.
A calib a ion cu e was i s es ablished by measu ing he abso bance o
a se ies o s anda d B-2,5-DHPV solu ions wi h known concen a ions.
To ob ain he es sample, B-2,5-DHPV was dissol ed in 1 M KOH
un il sa u a ion was eached, ollowed by he emo al o any
undissol ed solid h ough il a ion. The sa u a ed solu ion was
subsequen ly dilu ed o b ing a solu ion wi h abso bance wi hin he
linea ange o he calib a ion cu e, om which he concen a ion was
quan i ied.
3. RESULTS AND DISCUSSION
In o de o p o e ou p oposal, we conside ed o use he Zincke
eac ion ha allows he syn hesis o a amily o a yl iologen
Scheme 2. Syn he ic Rou es o he P epa a ion o (A) Ca boxyphenyl Viologen De i a i es AV-3a−e and (B) Hyd oxyphenyl
Viologen De i a i e AV-3
Figu e 2. Redox po en ials o a yl iologen de i a i es (AVs) a pH 14 including phenyl iologen PV.
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de i a i es (AVs) bea ing di e en a yl ings a ached o he
bipy idinium co e and unc ionalized a se e al posi ions wi h
acidic unc ional g oups, such as ee ca boxylic acids.
30−32
The
Zincke sal om 4,4′-bipy idine (1) was subjec ed o he Zincke
eac ion, an o e all amine exchange p ocess o p epa e N-alkyl
o N-a ylpy idinium sal s, using di e en es e - unc ionalized
anilines o yield iologen de i a i es 2a−e(Scheme 2A). A e
he comple ion o he eac ion and wi hou u he pu i ica ion,
acid hyd olysis led o he o ma ion o he co esponding
bis(ca boxyphenyl) iologen de i a i es AV-3a−e. On he o he
hand, an easy and s aigh o wa d access o 2,5-dihyd oxyphenyl
iologen B-2,5-DHPV (AV-3 ) was achie ed h ough he
Michael addi ion o bo h py idyl moie ies o p-benzoquinone,
allowing access o an a yl iologen unc ionalized wi h hyd oxyl
g oups (Scheme 2B).
33
De ailed syn he ic p ocedu es and
p oduc cha ac e iza ion a e p o ided in he Suppo ing
In o ma ion.
A map o edox po en ials o he syn hesized a yl iologens
AV-3a− a pH 14 along wi h phenyl iologen (PV)
34
is shown
in Figu e 2 ( he cyclic ol amme y esul o each o he p epa ed
compounds is p o ided in he Suppo ing In o ma ion; see
Sec ion S2). Rega ding he elec ochemical p ope ies o hese
iologen de i a i es, i should be no ed ha all o hem a e
elec oac i e compounds ha exhibi good e e sible beha io
in cyclic ol amme y in alkaline media. Fu he mo e, he edox
po en ial could be modula ed up o 400 mV, depending on he
na u e o he subs i uen s on he a yl g oups. The wi hd awing
and dona ing cha ac e s o he unc ional g oups ha e been
epo ed o in luence he edox po en ial o he molecules, so i is
an icipa ed ha he edox po en ial and hus he cell ol age can
be sligh ly uned by selec ing he p ope g oups.
35
The e o e, as
expec ed om he li e a u e, iologen AV-3 wi h elec on-
dona ing subs i uen s such as hyd oxyls p esen s a edox
po en ial mo e nega i e han ha o iologens AV-3a−e
subs i u ed wi h elec on-wi hd awing g oups such as ca boxyls.
These esul s indica e he high po en ial o a yl iologen
de i a i es as a p omising new amily o iologen-based anoly es
o AORFBs. The iologen de i a i e B-2,5-DHPV (AV-3 ) was
chosen o in es iga ion in ull cells due o i s easily accessible
syn hesis, low cos o s a ing ma e ials enabling mass
p oduc ion, and sui able edox po en ial.
Be o e using iologen B-2,5-DHPV in edox low ba e ies, i s
chemical s abili y in alkaline media was explo ed by using 1H
NMR. Figu e 3 shows he 1H NMR spec a o he s a e-o - he-
a iologen (SP )2V, iologen BS3Bu-Vi,
27
iologen (DBPPy)-
Cl4,
36
and he a yl iologen B-2,5-DHPV be o e and a e being
exposed o pH 14 by he addi ion o KOH. The uppe 1H NMR
spec um in Figu e 3A e eals he expec ed decomposi ion o
Figu e 3. Chemical s abili y s udies a pH 14 o he s a e-o - he-a iologen (SP )2V, wo iologens wi h inc eased s e ic hind ance (BS3Bu-Vi and
(DBPPy)Cl4), and a yl iologen B-2,5-DHPV (AV-3 ). (A) S acked 1H NMR spec a o (SP )2Va pH 14 o 5 min (blue) and a pH 7 ( ed). (B)
S acked 1H NMR spec a o BS3Bu-Vi a pH 14 o 5 min (blue) and a pH 7 ( ed). (C) S acked 1H NMR spec a o (DBPPy)Cl4a pH 14 o 5 min
(blue) and a pH 7 ( ed). (D) S acked 1H NMR spec a o B-2,5-DHPV a pH 14 o 24 h (blue) and a pH 7 ( ed). The expe imen s we e pe o med
in D2O as a sol en unde N2a mosphe e, and he pH was adjus ed using KOH and DCl. The pH was b ough back o neu al a e exposu e o alkaline
condi ion o be e compa ison.
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he iologen (SP )2V, which deg ades quickly in alkaline media
a e ca. 5 min o exposu e. The same decomposi ion p ocess has
also been obse ed in p e ious s udies.
15−18,27
Analogously,
BS3Bu-Vi and (DBPPy)Cl4(Figu e 3B,C), wo alkyl iologens
designed o p esen enhanced s abili y owa d he nucleophilic
a ack o hyd oxide anions by inc easing s e ic e ec s, su e ed
he same as decomposi ion p ocesses.
In con as , he a yl iologen B-2,5-DHPV emains chemi-
cally s able e en a e 24 h o exposu e a pH 14, wi h he spec a
eco ded be o e and a e his ime being iden ical, which
suppo s i s excellen chemical s abili y (Figu e 3D). These
esul s con i m ha changing he elec onic na u e o he ca bon
a oms, om C(sp3) (alkyl chain) o C(sp2) (a yl g oup), di ec ly
bonded o he N a oms o he bipy idinium co e allows o he
comple e inhibi ion o deg ada ion by clea age o he N-
subs i uen s ia nucleophilic a ack by he hyd oxide anions
unde alkaline condi ions. This highligh s ha a yl iologen
de i a i es a e ema kably mo e s able unde basic pH han alkyl
iologen de i a i es.
Ini ially, a s a ic ba e y es was conduc ed using iologen B-
2,5-DHPV as he anoly e o s udy i s cyclabili y in alkaline
condi ions, employing K4Fe(CN)6as he ca holy e (Figu e 4).
As he solubili y o B-2,5-DHPV in 1 M KOH was de e mined
o be 0.29 M, he concen a ion o B-2,5-DHPV in he anoly e
was se o 0.2 M o ensu e comple e dissolu ion. The anoly e
solu ion wi h a concen a ion o 0.2 M B-2,5-DHPV in 1 M KCl
and 0.8 M KOH eached a pH alue o 14. The simplici y o
s a ic cells acili a es he e alua ion o he in insic s abili y o he
compound.
37
The heo e ical cell ol age o B-2,5-DHPV//
K4Fe(CN)6is 0.98 V (Figu e 4A), a alue sligh ly supe io o he
(SP )2V//K4Fe(CN)6ba e y ol age, which enables a 0.81 V
cell (Figu e 4B). The esul s e eal an excep ional beha io due
o i s g ea cyclabili y o e mo e han 2000 cycles (14 days),
excellen Coulombic e iciency, and low capaci y ading
h oughou he ba e y pe o mance (0.024%·h−1), highligh ing
he po en ial u ili y o B-2,5-DHPV as an anoly e o alkaline
ba e ies (Figu e 4C,D).
Finally, a ull low cell was assembled using iologen B-2,5-
DHPV and K4Fe(CN)6as an anoly e and ca holy e, espec i ely
(Figu e 5). The cell demons a ed s able cycling a 30 mA·cm−2
o 21 days (1425 cycles) (Figu e 5B), wi h a 0.025%·h−1o
capaci y decay o e he las 1000 cycles, which is signi ican ly
be e han he 0.45%·h−1 epo ed by ou g oup o he s a e-o -
he-a iologen (SP )2Vin neu al media unde compa able
condi ions.
27
No ably, his capaci y e en ion alue in alkaline
media is compa able o some o he alues epo ed o iologen-
based anoly es in neu al pH.
23,38
Since he capaci y o he
ca holy e is 1.5 imes ha o he anoly e and he anoly e
c osso e a e is negligible (as con i med by pe meabili y
expe imen s; see Sec ion S3 o Suppo ing In o ma ion), he
capaci y ade is p ima ily a ibu ed o he decomposi ion o he
elec oac i e ma e ial in he anoly e. Fu he mo e, he
pe meabili y p esen ed by he a yl iologen B-2,5-DHPV was
se e al o de s o magni ude lowe han ha co esponding o
he s a e-o - he-a iologen (SP )2Vunde iden ical expe -
imen al condi ions. The pe meabili y alues o B-2,5-DHPV
and (SP )2Vwe e 6.35 ×10−11 cm2·s−1and 1.07 ×10−7cm2·s−1,
espec i ely (see Sec ion S3 o Suppo ing In o ma ion). This
signi ican di e ence is likely due o he la ge size o he a yl
iologen de i a i es. Impo an ly, he di usion coe icien alue
o 2.98 ×10−7cm2·s−1 o a yl iologen B-2,5-DHPV (see
Sec ion S4 o Suppo ing In o ma ion) was no signi ican ly
a ec ed by he inc eased size, as he alue is o he same o de o
magni ude as hose epo ed o o ganic anoly es in
Figu e 4. (A) CV cu es o B-2,5-DHPV and K4Fe(CN)6in 1 M KCl and 0.8 M KOH. The equilib ium po en ial o B-2,5-DHPV//K4Fe(CN)6is
0.98 V. (B) CV cu es o (SP )2Vand K4Fe(CN)6in 1 M KCl. The equilib ium po en ial o (SP )2V//K4Fe(CN)6is 0.81 V. (C) Cha ge and
discha ge p o iles o he B-2,5-DHPV//K4Fe(CN)6alkaline s a ic ba e y o cycle numbe s 2, 20, and 50. (D) E olu ion o he cha ge capaci y and
Coulombic e iciency o he s a ic cell upon cycling ha ing B-2,5-DHPV//K4Fe(CN)6in 1 M KCl and 0.8 M KOH (14 days).
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AORFBs.
39−42
Conside ing ha no app eciable deg ada ion
occu s om he nucleophilic a ack o hyd oxyls on he a yl
iologen B-2,5-DHPV, and ha he sys em exhibi s negligible
c osso e , we ini ially a ibu e he obse ed capaci y dec ease in
AORFB (Figu e 5) o he o ma ion o π−πagg ega es, as has
been epo ed o alkyl iologens when ope a ing in a glo ebox.
In addi ion, no e ha he syn hesized B-2,5-DHPV p oduc has
a pu i y o app oxima ely 95% and con ains ≈4% hyd a ion
molecules, as expe imen ally de e mined. Taking hese ac o s
in o accoun , he heo e ical capaci y, assuming a one-elec on
ans e , is es ima ed o be 0.059 Ah. Unde hese consid-
e a ions, he AORFB shown in Figu e 5 eaches an ini ial
capaci y o 93% o he heo e ical capaci y.
4. CONCLUSIONS
In summa y, o he bes o ou knowledge, his is he i s epo
demons a ing he easibili y o using a iologen de i a i e as he
anoly e in alkaline low ba e ies, capi alizing on he ad an ages
o e ed by such condi ions. Th ough he use o molecula
enginee ing, i is possible o imp o e he s abili y o elec oac i e
species. I has been p o en ha modi ying he elec onic na u e
o he a om in ol ed in he deg ada ion o iologens in an
alkaline medium is mo e sa is ac o y han solu ions based on
s e ic hind ance p e iously desc ibed in he li e a u e. These
esul s highligh he capabili y o iologens o unc ion
e ec i ely in s ong alkaline en i onmen s, con a y o p e ious
assump ions, hus expanding he ange o o ganic compounds
sui able o anoly e ma e ials in such sys ems. This inding pa es
he way o he de elopmen o new iologen-based elec oac i e
ma e ials in he ield o alkaline o ganic edox low ba e ies.
■ASSOCIATED CONTENT
*
sı Suppo ing In o ma ion
The Suppo ing In o ma ion is a ailable ee o cha ge a
h ps://pubs.acs.o g/doi/10.1021/acsaem.5c02255.
De ailed expe imen al syn he ic p ocedu es; 1H and 13C
NMR spec a and cyclic ol ammog ams o all
compounds; UV−Vis spec a o c osso e e alua ion;
and cyclic ol ammog ams o he di usion coe icien
de e mina ion (PDF)
■AUTHOR INFORMATION
Co esponding Au ho s
Rubén Rubio-P esa −Depa men o Chemis y, Uni e si y o
Bu gos, Bu gos E-09001, Spain; In e na ional Resea ch Cen e
in C i ical Raw Ma e ials-ICCRAM, Uni e si y o Bu gos,
Bu gos E-09001, Spain; o cid.o g/0000-0002-9938-
2058; Email: [email p o ec ed]
Edga Ven osa −Depa men o Chemis y, Uni e si y o
Bu gos, Bu gos E-09001, Spain; In e na ional Resea ch Cen e
in C i ical Raw Ma e ials-ICCRAM, Uni e si y o Bu gos,
Bu gos E-09001, Spain; o cid.o g/0000-0002-8993-
4285; Email: [email p o ec ed]
Robe o Sanz −Depa men o Chemis y, Uni e si y o Bu gos,
Bu gos E-09001, Spain; o cid.o g/0000-0003-2830-
0892; Email: [email p o ec ed]
Comple e con ac in o ma ion is a ailable a :
h ps://pubs.acs.o g/10.1021/acsaem.5c02255
Au ho Con ibu ions
The manusc ip was w i en h ough con ibu ions o all
au ho s. All au ho s ha e gi en app o al o he inal e sion o
he manusc ip .
No es
The au ho s decla e no compe ing inancial in e es .
■ACKNOWLEDGMENTS
The au ho s acknowledge he inancial suppo by he Spanish
Go e nmen (Minis e io de Ciencia e Inno ación, G an s
PID2021-124974OB-C22 and PID2023-148198NB-C21), he
Regional Go e nmen o Cas illa y León (Jun a de Cas illa y
León) and FEDER (BU028P23 and Nex Gene a ionEU/PRTR
C17.I1), and Ramón y Cajal awa d (RYC2018-026086-I), as
well as he MeBa e y p ojec . MeBa e y has ecei ed unding
om he Eu opean Inno a ion Council o he Eu opean Union
unde G an Ag eemen no. 101046742. The au ho s would like
o hank Rebeca Valenciano ( ebeca alenciano.com) o he a
in he ToC.
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