Reader in Physical Chemistry

B.Sc., D.Phil., (Sussex).

Tel: 0116 252 2088

email: ksr7@le.ac.uk

Research Interests

My research activities cover three main project areas detailed below.  Underpinning all these areas is an interest in electrochemistry, electrochemical interfaces and materials.  The research carried out at the University of Leicester, in collaboration with both Professor Abbott and Professor Hillman, is aimed at novel and interesting electrochemical processes and materials and draws upon many sate of the art techniques for surface and interfacial characterisation.  These include probe microscopy, x-ray photoelectron spectroscopy (NCESS) nueutron reflectivity (ILL, ISIS) electrochemical acoustic impedance spectroscopy and others.

Metal finishing from new Ionic Liquids

(with Prof Abbott); Project IONMET:

The Leicester group is at the centre of a large European network exploring the properties of novel ionic liquids as replacement technologies for the metal finishing industry.  These processes include metal plating, e.g. Zn, Ni, Cr and also electrochemical dissolution processes such as polishing.  The IONMET consortium consists of 33 partners both industrial manufacturers and academic researchers.  Our role at Leicester is to investigate the underlying science, physical chemistry and electrochemical properties of the new processes.

 The images below are taken from a study of electrochemical polishing of stainless steels.  They show a sample with both rough (native, unpolished) regions and the smoother electropolished regions.  The liquid used for this process is a very benign, non-toxic liquid that now provides an alternative to the traditional mixture of strong toxic inorganic acids.  These studies are also carried in conjunction with Scionix a University of Leicester spin-out company.

Above left: Scanning electron micrograph of partially polished sample of stainless steel.  Above right: Probe microscope (AFM) image of the same stainless steel sample.

Probe miscroscopy of electroative surfaces and thin film coatings

We are currently using atomic force microscopy (AFM) to study a variety of electrochemical interfaces e.g thin polymer films and metal electrode interfaces both in dry air and in liquid.  The latter provides a severe technological challenge but the Department has a new DI Nanoscope III instrument (pictured below) which represents the state of the art in probe microscopy.  This instrument also forms part of the University wide Advanced Microscopy Centre. 

Recently we have applied the AFM to the study of thin film electroactive polymer interfaces.  These have many uses in the emerging technology of plastic electronic devices.  The image below is taken of a polymer layer deposited on a thin film of gold supported but a quartz substrate.  The three layers of the sample can be clearly seen in  the 3D projection (left) and their relative thickness can be quantified using profilometry.

Picture left: AFM image of polymer sample: Quartz (red), Gold layer (orange), Polymer (yellow-blue). Picture right: Single profile slice of the AFM image.

Electronic and electroluminescent conducting polymers

In collaboration with Professor Mortimer at Loughborough University we are studying the properties of electronically conducting polymer materials that change colour as a function of applied potential.  These electrochromic materials have applications in display devices, smart mirrors and windows in controlled environments.  The diagram below shows a surface that defines the light absorption of a thin film of polymer as a function of time, where time is also related to potential.  At the starting time (t = 0) and the end time (t = 600 s) the polymer absorbs strongly in the red (ca 600 nm) so the material appears blue.  In the middle of the surface, however, the polymer is only weakly absorbing and so appears almost colourless! 

Picture left: Surface showing optical properties of a thin film of conducting polymer. Picture right: Electrochemical absorbance plot: absorbogram.

The slope of this surface (in the absorbance time plane) tracks with potential in a manner that is similar to the current (dQ/dt) indicating that charge injection and colour intensity are related. 

Selected Publications

1. "Electrolytic Metal Coatings and Metal Finishing Using Ionic Liquids", A.P. Abbott, J.C. Barron, M. Elhadi, G. Frisch, S.J. Gurman, A.R. Hillman, E.L. Smith, M.A. Mohamoud and K.S. Ryder, ECS Trans., 2008, (in press).
2. "Nanogravimetric observation of unexpected ion exchange characteristics for polypyrrole film p-doping in a deep eutectic ionic liquid", Magda A. Skopek, Mohamoud Mohamoud , Karl S. Ryder and A. Robert Hillman, Chem. Commun., 2009, 935.
3. “Use of Neutron Reflectivity to Measure the Dynamics of Solvation and Structural Changes in Polyvinylferrocene Films During Electrochemically Controlled Redox Cycling”, A. Robert Hillman, Karl S. Ryder, Emma L. Smith, Andrew Glidle, Jon Cooper, Nikolaj Gadegaard, John R.P. Webster, Robert Dalgliesh and Robert Cubitt, Langmuir, 2009, (in press).
4.  “Electrodeposition of Copper Composites from Deep Eutectic Solvents Based on Choline Chloride”,  Andrew P. Abbott, Khalid El Ttaib, Gero Frisch, Katy J. McKenzie, and Karl S. Ryder, Phys. Chem. Chem. Phys., 2009, (in press).
5. “Electrolytic Deposition of Zn Coatings from Ionic Liquids based on Choline Chloride”, Andrew P. Abbott, John C. Barron and Karl S. Ryder, Trans. IMF, 2009, (in press).
6. “Metal Complexation in Ionic Liquids”, Andrew P. Abbott, Gero Frisch and Karl S. Ryder, Annu. Rep. Prog. Chem., Sect. A: Inorg. Chem., 2008, 104, 21-45.
7. “Electrodeposition of Nickel using a Eutectic based Ionic Liquid”, Andrew P. Abbott, Khalid El Ttaib, Karl S. Ryder, and Emma L. Smith, Trans. IMF, 2008, 86, 234.
8. “Electrofinishing of Metals using Eutectic Based Ionic Liquids”, Andrew P. Abbott, Karl S. Ryder and Uwe Koenig, Trans. IMF, 2008, 86, 196.
9.  “Sustained Electroless Deposition of Metallic Silver from a Choline Chloride-Based Ionic Liquid”, Andrew P. Abbott, Jason Griffith, Satvinder Nandhra, Cecil O’Connor, Stella Postlethwaite, Karl S. Ryder and Emma L. Smith, Surf. Coat. Tech., 2008, 202, 2033.
10. “Spectroelectrochemical Responses of Thin Film Conducting Copolymers Prepared Electrochemically from Mixtures of 3,4-Ethylenedioxythiophene and 2,2-Bithiophene”, Emma L. Smith, Andrew Glidle, Roger J. Mortimer and Karl S. Ryder, Phys. Chem. Chem. Phys., 2007, 9, 6098.