In the future, photovoltaic cells could be ‘worn’ over clothes, placed on cars or even on beach umbrellas. These are just some of the possible developments from a study published in Nature Communications by researchers at the Physics Department of the Politecnico di Milano, working with colleagues at the University of Erlangen-Nuremberg and Imperial College London.
The research includes among its authors the Institute of Photonics and Nanotechnology (IFN-CNR) researcher Franco V. A. Camargo and Professor Giulio Cerullo. It focused on photovoltaic cells made using flexible organic technology. Today’s most popular photovoltaic cells, based on silicone technology, are rigid and require a sophisticated and expensive infrastructure to manufacture them and have high disposal costs.
An alternative to replace silicon in the future is ‘plastic’ solar cells, in which a mixture of two organic semiconductors, one electron donor and an electron acceptor, absorbs light energy and converts it into electrical energy. Using organic molecules brings several advantages, such as simpler technology, reduced production and disposal costs, mechanical flexibility, and access to organic materials’ chemical diversity. However, organic materials have more complex physics than crystalline inorganic materials (such as silicone), particularly for charge transfer processes at donor-acceptor interfaces, which cause efficiency losses.
After four years of work, the researchers succeeded in creating solar cells with new materials in which losses due to interface states are minimised. By studying these materials with ultra-short laser pulses, they identified the physical reasons behind this exceptional performance, presenting a general optimisation model valid for other material combinations.
Future photovoltaic cells made from organic technology will be a cheaper source of energy with less environmental impact. They can be incorporated into various everyday objects such as windows, cars, or even clothes and coats because of their mechanical flexibility.
The study falls within the scope of renewable energy, as one of the critical challenges for humanity’s future is the development of clean and renewable sources of energy. The Earth’s primary energy source is sunlight, which provides more than 100 times more energy daily than humanity needs, making photovoltaic technologies among the most promising for the future.
With its climate and few clouds, Italy has one of the most considerable photovoltaic potentials in Europe, comparable to that of non-desert tropical countries.
Politecnico di Milano is a scientific-technological university which trains engineers, architects and industrial designers.
The University has always focused on the quality and innovation of its teaching and research, developing a fruitful relationship with business and productive world by means of experimental research and technological transfer.
Research has always been linked to didactics and it is a priority commitment which has allowed Politecnico Milano to achieve high quality results at an international level as to join the university to the business world. Research constitutes a parallel path to that formed by cooperation and alliances with the industrial system.
Knowing the world in which you are going to work is a vital requirement for training students. By referring back to the needs of the industrial world and public administration, research is facilitated in following new paths and dealing with the need for constant and rapid innovation. The alliance with the industrial world, in many cases favoured by Fondazione Politecnico and by consortiums to which Politecnico belong, allows the university to follow the vocation of the territories in which it operates and to be a stimulus for their development.
The challenge which is being met today projects this tradition which is strongly rooted in the territory beyond the borders of the country, in a relationship which is developing first of all at the European level with the objective of contributing to the creation of a single professional training market. Politecnico takes part in several research, sites and training projects collaborating with the most qualified European universities. Politecnico’s contribution is increasingly being extended to other countries: from North America to Southeast Asia to Eastern Europe. Today the drive to internationalization sees Politecnico Milano taking part into the European and world network of leading technical universities and it offers several courses beside many which are entirely taught in English.
Politecnico di Milano is partner of the following outstanding international networks: IDEA League, Alliance4Tech, UNITECH International Society, T.I.M.E. (Industrial Managers in Engineering), MEDes, Magalhães Association, Pegasus, Global Engineering Education Exchange (E3), Athens, QTEM Quantitative Techniques for Economics and Management.