Chemistry Reference
In-Depth Information
1
Introduction to
Electrochemistry and
Electroanalysis with Carbon
Paste-Based Electrodes
1.1 HISTORICAL SURVEY AND GLOSSARY
“During.an. investigation. of. the. properties. of. a. dropping. carbon. electrode,. a. new. paste. electrode.
has.been.developed.which.possesses.unique.advantages.in.anodic.polarography..…”.says.an.open-
ing.sentence.of.the.irst.report.on.carbon.paste.electrode.(CPE).with.a.laconic.title.
Carbon Paste
Electrodes
.[1]..The.author.of.this.text,.Ralph.N..Adams.(Appendix.A),.had.thus.stepped.into.the.
history.as.the.inventor.of.carbon.paste.for.electrochemical.and.electroanalytical.measurements.
The.aforementioned.formulation.reveals.that.it.happened.more.or.less.coincidentally,.when.the.
background.of.the.discovery.was.mentioned.in.the.inventor's.irst.review.on.CPEs.[2].and,.some.
years.later,.revealed.fully.in.his.monograph.[3]..Therein,.on.page.280,.one.can.read.as.follows:
….Carbon.paste.electrodes.developed.from.an.attempt.to.prepare.a.luid.of.suspended.carbon.particles.
to.be.used.in.the.sense.of.a.dropping.electrode.for.anodic.oxidations..Such.a.mixture.can.be.prepared.
and. dropped. from. a. capillary. of. internal. bore. slightly. greater. that. that. of. the. DME.. However,. the.
conditions. for. successful. operation. of. the. dropping. carbon. paste. electrode. are. far. from. ideal,. and. it.
soon.became.apparent.that.a.thicker.paste,.packed.in.a.pool.coniguration.and.used.either.stationary.or.
rotated,.would.be.far.more.advantageous.…
Finally,.these.circumstances.were.also.conirmed.by.
Theodore Kuwana
,.Adams's.former.student.
[4,5],.the.author.of.a.special.foreword.in.this.topic,.and.one.of.the.irst.electrochemists.who.had.ever.
worked.with.carbon.paste..During.a.short.meeting.with.the.authors.a.decade.ago.[6],.he.said.that.he.
was.“the.slave”.who.had.been.working.in.the.laboratory.with.the.dropping.carbon.electrode.(DCE).
during.the.experimental.testing.of.this.device,.as.well.as.with.the.very.irst.carbon.paste.mixtures.
made.afterward..Despite.some.initial.optimism.(see.the.Adams's.concluding.words.in.his.pioneer-
ing.report.[1]),.the.whole.concept.of.the.DCE.failed;.nevertheless,.the.unsuccessful.work.with.luid.
graphite. suspensions. had. resulted. in. an. unexpected. side. product—the. carbon. paste.. In. addition,.
the.mixtures.of.this.consistency.soon.became.so.popular.that.carbon.pastes.as.such.represented.the.
classic.electrode.material.for.laboratory.preparations.of.electrodes,.sensors,.and.detectors.of.innu-
merable.types,.sizes,.and.conigurations.
Before.having.achieved.such.a.position,.however,.the.carbon.paste-based.electrodes.had.under-
gone.a.very.interesting.genesis,.comprising.a.number.of.signiicant.developments.and.achievements..
It.may.even.be.stated.that.there.is.scarcely.another.type.of.electrode.material.whose.employment.
would.illustrate.more.faithfully.the.overall.progress—or,.on.the.contrary,.the.individual.movements.
and.trends—in.electrochemical.and.electroanalytical.measurements.over.half.a.century—across.the.
time.period.of.existence.of.carbon.paste.[7].
The.era.of.carbon.paste-based.electrodes.can.then.be.summarized.by.means.of.the.following.
periods.and.key.moments.
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