Meng, Lingcong (2016) Thermo-electrochemistry of boron doped diamond from fundamentals to application. PhD thesis, University of Warwick.

Preview

PDF WRAP_Theses_Meng_2016.pdf - Submitted Version - Requires a PDF viewer. Download (9Mb) | Preview

Request Changes to record.

Abstract

Boron doped diamond (BDD), due to its exceptional electrochemical response (extended solvent window and low background current) and thermal properties (large thermal diffusivity and extreme resistance to thermal ablation), is investigated as the electrode material for thermoelectrochemical studies. A pulsed infrared (IR) laser technique is used to heat the electrode from the back (nonsolution) side. The non-isothermal pulsed technique enables mass transport to be more readily controlled as opposed to isothermal heating approaches such as a water bath.

The effect of temperature on fundamental electrochemical processes, such as mass transport, electron transfer (ET) kinetics and thermodynamics of both outer sphere and inner sphere redox mediators is investigated on both BDD macro- and micro- electrodes. The effective temperature increase at electrode surface can be determined both experimentally and theoretically using finite element models. Enhanced mass transport and ET process at elevated temperatures, in addition to the temperature coefficient of the redox mediators, play a crucial role in the temperature dependent electrochemical response.

Thermoelectrochemical studies are extended to an electroactive species which forms a solid structure after electrolysis. In particular, the cathodic electrodeposition of lead/lead oxide (Pb/PbO) under non-isothermal heating conditions in nitrate containing solutions is investigated. The effect of deposition potential, time, dissolved oxygen content and temperature are explored to understand the mechanism for the synthesis of crystalline PbO “plate” structures, and the role of electrodeposited Pb.

Further work explores the effect of temperature on an electroactive species which upon electrolysis forms a solid product which fouls the electrode surface. Using a BDD microelectrode it is possible to show how temperature can be used to minimise the effect of surface blocking after the oxidation of a neurotransmitter, dopamine, which is known to lead to electrode fouling.

Finally, proof of concept studies are undertaken to assess the suitability of a thermoelectrochemical approach to the detection of single nucleotide polymorphism (SNP) in deoxyribonucleic acid (DNA). Initial studies investigate immobilisation strategies for both (in separate experiments) electrochemically active self-assembled monolayers (SAM) and redox-labelled double stranded DNA on gold and BDD electrodes.

Item Type:	Thesis or Dissertation (PhD)
Subjects:	Q Science > QD Chemistry
Library of Congress Subject Headings (LCSH):	Electrochemistry, Diamonds -- Thermal conductivity, Diamonds -- Electric properties, Boron -- Electric properties, Electrodes
Official Date:	September 2016
Dates:	Date Event September 2016 Submitted
Institution:	University of Warwick
Theses Department:	Department of Chemistry
Thesis Type:	PhD
Publication Status:	Unpublished
Supervisor(s)/Advisor:	Macpherson, Julie V. ; Newton, Mark E.
Sponsors:	University of Warwick. Chancellor International Scholarship
Format of File:	pdf
Extent:	xxiv, 206 pages : illustrations, charts
Language:	eng

Request changes or add full text files to a record

Repository staff actions (login required)

View Item

Downloads