Research

Research Overview

Our research is focused on supramolecular materials chemistry where coordination chemistry of d– and f– block metals is exploited in order to generate new functional devices including, sensors (colorimetric and fluorescent/luminescent), switchable materials for nanoelectronics and light emitting devices based on organic and lanthanide containing chromophores. An important aspect of this research is ligand design, each area of research requires rational ligand design so the desired (bi)functionality is built into the ligands. We invest significant effort into developing new heterocyclic ligands that combine both metal chelating pockets as well as interesting supramolecular constructs (i.e. H-bonding groups, long alkyl chains, other metal binding sites, anion recognition sites, etc.).

Of particular interest is the immobilisation of coordination complexes onto surfaces using Langmuir-Blodgett (LB)techniques. LB allows for the controlled deposition of mono- and multi-layers, a useful technique for new soft materials for application in a range of different areas.

 


 

Surface immobilised sensors using Langmuir-Blodgett techniques

The development of new generation sensors and probes with improved sensitivity and selectivity is required for remote sensing, detection of concealed materials, and detection/response before hazardous concentration levels are reached. Preparing and assessing new systems that can be readily immobilised, for example onto surfaces, represent the next big challenge towards functional devices composed of complex sensor systems which are capable of sensing and discriminating between multiple inputs, e.g. detecting different enantiomers, chemical hazards, and specific anions in competitive media.

We have a program of research underway that is investigating the development of amphiphilic luminescent LnIII coordination compounds that respond, via changes in photophysical output, to binding events and can be immobilized onto surfaces with exquisite control via Langmuir-Blodgett methods.

LB trough

Links:

 


 

Modification of material surface properties using Langmuir techniques

Langmuir techniques allow for the formation of highly ordered monolayers of amphiphiles at an interface. Manipulating the formation of these monolayers can result in significantly different properties (e.g. emission properties, magnetic properties etc.).  We are investigating methods in which we can modify the surface structures and properties through simple ligand modification, multiple amphiphile films, and sub-phase composition. This allows us to fine tune the properties of our systems and undertake systematic structure-function investigations at an interface.  Such “surface engineering” approaches allow us to develop more complex and advanced functional nano-materials.  An integral aspect of this is the study of surface morphology through techniques such as UV/vis, fluorescence and Brewster Angle Microscopy (BAM).

                     Isothermdeposition

 


 

Supramolecular materials based on 1,8-Naphthalimides

1,8-Naphthalimide derivatives can display interesting photophysical and structure directing properties. Through careful ligand design we have been developing luminescent supramolecular synthons for novel soft materials (gels and polymers) and coordination polymers for the development of 2D-layer materials for supramolecular spintronics.

       Gels and structure                      abstract image

 


 

Switchable (spin crossover) soft materials

We are developing Fe(III) Spin Crossover (SCO) complexes where ligand modification allows us to manipulate the larger structure through incorporation of functional groups for structure extension. Such an approach allows fine-tuning of spin state switching and also allows solution processability into SCO based soft materials such as LB films and gels. This approach also allows us to develop stable, magnetically interesting/switchable sub-components that we can use to build larger extended network solids through supramolecular approaches (e.g. metal, anion or cation directed network/framework materials). Again the switchable nature of such systems can be used for the development of sensor systems – in this instance temperature and pressure can induce the SCO.
 


 

SustainAbility

We are interested in modifying our working practices to operate under more sustainable conditions. This includes reducing our water use, power use, waste disposal and introducing new lab recycling schemes. We have also been investigating the optimisation of reactions in order to improve yields and time, which in turn moves towards a more sustainable lab. Together with other members of the department we have successfully begun a program to change the attitudes towards sustainable practice in Southampton Chemistry. Full details of all projects and funding success can be found on our SustainAbility website.
 

Collaborators