EPSRC Reference: |
EP/C004906/1 |
Title: |
Supertetrahedral building blocks as a route to novel microporous semiconductors |
Principal Investigator: |
Vaqueiro Rodriguez, Dr P |
Other Investigators: |
|
Researcher Co-Investigators: |
|
Project Partners: |
|
Department: |
Sch of Engineering and Physical Science |
Organisation: |
Heriot-Watt University |
Scheme: |
Standard Research (Pre-FEC) |
Starts: |
03 October 2005 |
Ends: |
02 October 2008 |
Value (£): |
102,463
|
EPSRC Research Topic Classifications: |
Materials Characterisation |
Materials Synthesis & Growth |
|
EPSRC Industrial Sector Classifications: |
|
Related Grants: |
|
Panel History: |
|
Summary on Grant Application Form |
This project will exploit a high throughput approach for the synthesis of innovative multifunctional materials based on gallium sulphide frameworks. The building units of these materials are supertetrahedral clusters, which can be described as tetrahedrally shaped fragments of the cubic ZnS-type lattice. Each supertetrahedral cluster can contain over 200 atoms, and the cluster dimensions can range from 0.5 to 3 nm, depending on the synthetic conditions. By replacing regular tetrahedra with supertetrahedral clusters in structures such as diamond, crystalline microporous solids with large pores, representing more than 80% of their crystal volume, can be generated. Compared to microporous oxides, which are usually insulators, open-framework sulphides can have a substantially higher electrical conductivity, which combined with uniform porosity on a nanometer scale, may find applications in the fields of nanotechnology, molecular sieve science and optoelectronics. The emerging importance of supertetrahedral microporous solids is evidenced by the increasing number of publications in high impact journals (e.g. Nature, JACS, Science) in recent years. However, the systems investigated to date are primarily those of indium and germanium, and little is known about the related gallium sulphides. This project will develop a new family of microporous gallium sulphides, which are particularly interesting because they are expected to exhibit band gaps close to 3 eV and to be optically transparent in the visible region. Transparent semiconductors, particularly those of p-type, are rare, but highly desirable for optoelectronic applications. As a large proportion of these open-framework materials exhibits noncentrosymmetric structures, they might also have applications as nonlinear optical materials. These materials will be prepared by solvothermal synthesis, a process that involves the use of polar solvents in sealed containers at temperatures above their boiling point. Autoclaves containing multiple reaction wells will be fabricated in-house and will allow a large number of reactions to be carried out in parallel. The use of this equipment will increase the rate and efficiency at which experimental data will be generated. Multivariate methods will be used for the design of the combinatorial experiments and for the analysis of the experimental data. Measurement of the physical properties will be an integral part of the project, and will involve the determination of the semiconducting behaviour, and the optical and magnetic properties. Diffuse reflectance measurements, which allow the determination of the band gap, will be used for the rapid screening of the materials generated by the synthetic program, while more time consuming measurements will be carried out on selected materials.
|
Key Findings |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
|
Potential use in non-academic contexts |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
|
Impacts |
Description |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk |
Summary |
|
Date Materialised |
|
|
Sectors submitted by the Researcher |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
|
Project URL: |
|
Further Information: |
|
Organisation Website: |
http://www.hw.ac.uk |