Carbon Pastes and Carbon Paste Electrodes - Electroanalysis with Carbon Paste Electrodes - page 34

aforementioned. classiication—one. can. quote. (i). BPPF6,. HPPF6,. OPPF6,. (ii). C4MPyNTf2,. (iii).
BMIMPF6,.HMIMPF6,.OMIMPF6,.PMIMPF6,.EMIMBF4,.BMIMBF4,.etc.,.where.“M”.denotes.
“methyl”;. “E”. ethyl;. “B”. n -butyl;. “H”. n -heptyl;. “O”. n -octyl;. “P”. phenyl,. as. well. as. pyridinium;.
“Py”. pyrrolidinium. and. “IM”. imidazolium.. Despite. this. variability,. there. are. two. ionic. liquids.
whose.use.substantially.prevails.over.the.others:.BPPF6.and.BMIMPF6.
In.carbon.paste.mixtures,.an.(RT)IL.can.be.used.as.(i).additional.component.(usually.as.a.modi-
ier.enabling.some.of.the.facilities.pointed.out.earlier).or.(ii).special.binder.replacing.the.original.
pasting.liquid.and.contributing.with.its.own.typical.properties..Here,.one.should.note.that.some.(RT)
ILs.can.be.nearly.solid.substances.(e.g.,.OPPF6),.thus.giving.rise.to.a. solid-like carbon ionic liquid
composite .[478]..Otherwise,.the.two.basic.approaches.(i).and.(ii).can.be.mutually.combined,.which.
resembles. the. variability. among. CNTs-based. electrodes. and. the. classiication. of. (RT)IL-based.
counterparts.can.therefore.be.made.in.a.similar.way:
(I) Ionic liquid-modiied carbon paste electrodes (IL-CPEs) .. This. coniguration with three
components .in.the.paste.mixture.opens.the.list.as.“historically”.irst.[125].and.to.date.quite.
frequent.category.[126,415,453,459,465,468,505,513].
(II) Carbon ionic liquid electrodes ..A.qualitatively.new.type.of.CPEs.introduced.under.this.
name—or.as. Carbon Composite Ionic Liquid Electrodes ,.respectively—by.Maleki.et.al..
[453]. represents,. at. present,. the. largest. group. of. IL-based.CPEs. (see,. e.g.,.[126,448,454,
455,457,477,485,492,503,514]).. Similar. to. traditional. carbon. pastes,. they. also. form. two-
component .( binary ).mixtures,.but.with.the.alternate.pasting.liquid.moiety.
.(III) Carbon nanotubes ionic liquid electrodes (CNTILEs) .. The. respective. composites. are.
“younger”.than.both.previous.types,.but.also.popular.(e.g.,.[127,410,412,448,471]),.being.
truly.a.new.kind.of.CPEs,.where.both.major.constituents.are.replaced.by.alternate.materials.
(IV) Carbon-nanotubes ionic-liquid ilm electrodes .. Besides. standard. conigurations. of.
CNTILEs,.it.is.possible.to.mention.again.the.constructions,.where.a.very.thin.layer.of.the.
CNTs.+.IL.mixture.is.attached.to.the.surface.of.a.foreign.electrode.(either.the.CILE.itself.
[481],.a.common.CPE.[479],.or—more.often—the.polished.disc.of.the.GCE.[204,333,334]),.
all.serving.as.the.support.and.current.collector..In.some.cases,.the.composite.layer.contains.
also.additional.constituent(s)/stabilizer(s).in.one.integrated.system.[204,479,503,512].
(V) Chemically and biologically modiied IL-CPEs, CILEs, and CNTILEs ..Of.course,.also.
these. conigurations. allow. one. to. modify—upon. request—the. respective. native. mix-
tures,.when.the.concrete.examples.can.easily.be.found.in.the.existing.databases..Thus,.
it. is. possible. to. have. (i). the. “CM-IL-CPE”. type. (see,. e.g.,. [508]),. (ii). “CM-CILE”.
[126,482,504],.and.(iii).“CM-CNTILE”.[394,509],.or.CIL-.and.CNTIL-biosensors.(e.g.,.
[475,497].and.[414]).
(VI) Combinations of new types of carbon (graphite) with ionic liquids ..The.paste.mixtures.that.
do.not.contain.any.of.the.two.traditional.components.form.a.small.group.of.unique.and.
interesting.electrodes.but.with.marginal.signiicance.when.compared.to.the.types.(I-IV).
[452]..Hitherto.proposed.prototypes.of.mixtures.with.(RT)ILs.have.contained.the.follow-
ing.carbon/graphite.materials:.(i).glassy.carbon.microspheres.(“GC-ILE”.type.[486]),.(ii).
carbon. nanoibers. (“CNF-ILE”;. [128]),. and. (iii). graphene. (“GR-ILE”;. [507]).. Because.
these.carbon.pastes.can.also.be.chemically.modiied.(see,.e.g.,.[128].and.a.reagent.attached.
in situ . to. provide. a. chemiluminescent. signal),. the. overall. variability. of. IL-based. CPEs.
seems.to.be.yet.wider.than.that.described.earlier.for.both.CNT-CPEs.and.CNTPEs.
Finally,. there. is. also. a. unique. application. of. an. (RT)IL. in. measurements. with. carbon. paste-
based.electrodes—a.study,.in.which.the.ionic.liquid.had.been.preheated.up.to.60°C.and.then.used.
as.the.supporting.medium.for.testing.a.temperature-resistant.CNTPE.[406].
As. instrumental. techniques. of. choice. to. be. coupled. with. IL-based. CPEs,. very. frequent. were.
voltammetric. measurements. (see,. e.g.,. [126,453-459,469,488,500,513]),. including. the. effective.