Catechol adsorption on graphene nanoplatelets: isotherm, flat to vertical phase transition and desorption kinetics. Issue 7 (11th May 2017)

• Record Type: Journal Article
• Authors: Chen, Lifu; Li, Xiuting; Tanner, Eden E. L.; Compton, Richard G.
• Is Part Of: Chemical science. Volume 8:Issue 7(2017)
• Page Start: 4771
• Page End: 4778
• Publication Date: 2017-05-11
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7sc01331k
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : UV-Vis and nano-impact experiments are presented here as a powerful method for probing adsorption and desorption of molecules on nanomaterials. Abstract : The adsorption of catechol (1, 2-dihydroxybenzene) on graphene nanoplatelets (GNPs) is investigated electrochemically and spectroscopically. The reversible adsorption of catechol on GNPs is Langmuirian with an adsorption constant of (0.2 ± 0.002) mM −1 at low adsorbate concentrations (≤100 mM). At higher concentrations (>100 mM) the adsorption of catechol on GNPs is shown to undergo a flat to vertical concentration driven phase transition. The kinetics of desorption are measured with a single particle electrochemical technique. The study of individual impacts allows the determination of the rate of catechol desorption from GNPs to be k = 0.08 ± 0.01 s −1 with first order kinetics. The method provides a powerful and efficient generic approach to study adsorption and, importantly, desorption of molecules on nanomaterials, as well as giving insight into the modification process.