Modifikacija površine grafen-oksidnih elektroda molekulama anilina

undergraduate thesis

• Title (english): Modification of the graphene oxide electrode surfaces with aniline
• Author: Marija Filip
• Mentor: Zoran Mandić (mentor)
• Committee member: Zoran Mandić (predsjednik povjerenstva)
• Committee member: Stjepan Milardović (član povjerenstva)
• Committee member: Suzana Sopčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2016-09-20, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

U ovom radu pripremljene su i ispitane dvije elektrode od grafenovog oksida. Na zlatom prevučene kvarcne elektrode procesom "spin coatinga" nanesen je grafenov oksid, a zatim je provedena modifikacija površine grafen-oksidnih elektroda molekulama anilina s ciljem dobivanja elektroda s boljim kapacitivnim ponašanjem i boljom vodljivošću za potencijalnu primjenu u superkondenzatorima. Elektrode se razlikuju prema načinu vezanja anilina na funkcionalne skupine grafenovog oksida, a u to svrhu pripremljene su dvije otopine anilina u 1 M H2SO4 i u 1 M NaOH. Ispitivanja modificiranih grafen-oksidnih elektroda provedena su metodom cikličke voltametrije i pomoću elektrokemijske kvarc-kristalne nanovage. Ispitivanja su pokazala da se puno veća količina anilina vezala iz 1 M H2SO4 (elektroda 1) u odnosu na 1 M NaOH (elektroda 2), a to je najbolje vidljivo u izgledu cikličkih voltamograma. U slučaju elektrode 1 već su u prvim ciklusima vidljivi strujni vrhovi na potencijalima od 0,2 V te 0,4 V, dok takav trend izostaje kod elektrode 2. Tek kod ispitivanja elektrode 2 pri različitim brzinama promjene potencijala dolazi do pojave strujnih vrhova na potencijalu od 0,4 V što je rezultat oksidacije male količine vezanog anilina. Strujni vrh koji se javlja na potencijalu od oko 0,2 V karakterističan je za prijelaz između leukoemeraldinskog i emeraldinskog oblika polianilina, iz tog razloga elektroda 1 pokazuje dobru vodljivost električne struje, dobra elektrokemijska svojstva te obećavajuće rezultate za primjenu u superkondenzatorima.

Abstract (english)

In this paper two graphene oxide electrodes were prepared and tested. Graphene oxide was applied on gold coated quartz electrodes through "spin coating" process and afterwards the modification of the surface of graphene oxide electrodes with molecules of aniline was conducted with a goal of preparing electrodes with greater capacitance behaviour and greater conductivity for potentional application in supercapacitors. Two types of electrodes were prepared, one from aniline solutions in 1 M H2SO4 and another in 1 M NaOH. The examinations of the modified graphene oxide electrodes were conducted by cyclic voltammetry method and by means of electrochemical quartz chrystal nanobalance. The tests have shown that much greater amount of aniline was bound from 1 M H2SO4 (electrode 1) in comparison to 1 M NaOH (electrode 2), which is best apparent from the shape of cyclic voltammograms. In the case of the electrode 1, already in the first cycle the redox peaks at potentials of 0,2 V and 0,4 V can be seen, while they are absent in the case of the electrode 2. However, while testing the electrode 2 at differenent scan rates the redox peak at potentials about 0,4 V appeared which is the result of the oxidation of the small amount of bound aniline. The redox peak that appears at the potential of about 0,2 V is specific for the transition between the leucoemeraldine and emeraldine forms of polyaniline and for that reason the electrode shows good conductivity, good electrochemical features and promising results for the application in supercapacitors.

• Keywords: grafenov oksid; anilin; modifikacija; superkondenzatori
• Keywords (english): graphene oxide; aniline; modification; supercapacitors
• Language: croatian
• URN:NBN: urn:nbn:hr:149:585848
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-02-08 13:05:05