Final Report Summary - NATAMA (Nano engineered titania thin films for advanced materials applications)
Strategies for inducing visible light activation of titania include the exploitation novel nano-architectures, creation of nano-composite systems, and the doping such materials with small amounts of foreign atoms such as boron, carbon or nitrogen. A major obstacle to progress has been the lack of understanding of the relationship between synthetic method, nano-architecture, the structure of these substances at the atomic level and the desired physico-chemical properties. Achieving this understanding was one of the main goals. Moreover, for practical applications to be realized, it is important that synthetic methods be developed that are reproducible, low-cost and capable of being scaled up: this was the second major aim of the NATAMA project.
During the project, the research team developed a variety of new thin film fabrication methods and analyzing in detail the physical and chemical properties of the resulting materials using a range of state of the art experimental techniques. The work was carried out by a consortium comprised of four academic and two industrial partners with well-matched and complementary skills and experience, drawn from three countries and including two end-users who between them cover the main areas envisaged for exploitation of the results.
The work was carried out by means of interdependent work packages, each with its own leader, and designed to exploit the complementary strengths of the partners. New nanostructured materials incorporating precisely engineered architectures were created, produced as thin films, and optimised with respect to the intended application, the most important of which is the use of sunlight to generate hydrogen from water.
An important aspect of the project was the development of methods for coating large areas with these multi-functional solar-activated materials, ultimately to enable practical applications. A very promising method for depositing chemically modified titania thin films over large areas was developed by one of the industrial partners.
All the methods used for synthesising the photo-functional titania thin films were new and have never previously been described. The culmination of these activities was reached during the final stages of the project with the production scaled-up samples of the most promising thin film materials. These were then tested using sunlight at the Abengoa Solar facility located near Seville.
A very successful ancillary project was executed which involved the application of a new method for applying a protective coating to the optical lenses used for concentrating sunlight for use in high intensity photovoltaic technology. The coating produced three beneficial effects:
(i) it protects the lenses against damage by ultraviolet light radiation;
(ii) it creates a so-called hydrophilic (water-attracting) surface that enables self-cleaning of the lenses by rainwater;
(iii) it provides anti-reflective properties that improve light transmission through the lens. These lenses have performed well in field trials.
In summary, the NATAMA project has met all its stated objectives. Nano-structured thin film materials chemically modified so as to produce desirable physico-chemical photo-responses under the influence of visible light were successfully produced. These best of these materials were at least as effective as or better than those already available under current state of the art. Moreover, 'wet' and 'dry' methods for coating were invented, such as visible light-activated thin films on much larger surface areas than previously achieved, opening the door to practical implementation. Medium to long term benefits for European competitiveness (especially for small and medium-sized enterprises (SMEs)) are expected in regard to the development of coating equipment and technology, solar technology, anti-microbial coatings for medical equipment and purification of water and ambient air.