Researchers at the University of Surrey’s Advanced Technology Institute announce carbon nanotube solar cell with record efficiency
Monday 7 January 2013
The availability of efficient photovoltaic solar cells with large area and low manufacturing cost would transform the global economics of energy production. An international research effort is pursuing this goal by developing new materials, structures and device concepts. The main focus has been on organic materials, which are suitable for cost-effective manufacture on a large scale and can be produced with large active areas on cheap, flexible substrates. Unfortunately, their efficiency is still low compared to the best traditional photovoltaic materials, and those with the highest efficiency suffer from limited lifetimes or sensitivity to the environment.
One approach to improving these materials is to combine them with inorganic materials, in particular by using new nanostructured materials that are compatible with the lost-cost manufacturing processes for organic photovoltaics. The inorganic nanostructures can improve the functionality and performance in a range of different ways, for example by boosting the light capture or facilitating the transport of electric charge from the device to the external circuit. Carbon nanotubes are particularly interesting because, in addition to having photonic and electronic properties that are both useful and controllable, they are extremely stable and robust materials.
Researchers at the University of Surrey’s Advanced Technology Institute have reported a new material consisting of polymer-wrapped carbon nanotubes that has a unique combination of properties related to light capture, efficient use of electrical energy and manufacturability. It can replace commonly-used polymers which have limited lifetimes due to moisture absorption. The potential of this material has already been demonstrated by the construction of a solar cell with power conversion efficiency of 7.6% - a record for nanotube-based solar cells which improves on previous performance by 35%. In addition to the application in solar cells, the new material may find applications in light-emitting devices and displays, sensors, and printable electronics for tags, for example.
The research team was led by Professor Ravi Silva who remarked:
“The combination of organics materials with nanotechnology is starting to look very promising for electronic and photonic devices and systems with better performance or new capabilities. It is only by combining the expertise of researchers specialising in material synthesis, device production, advanced characterisation and theoretical modelling that this new landscape of materials can by fully explored and the benefits realised. Improving the availability and security of energy is one of the most tangible ways that scientists and technologists can contribute to future generations and society.”
The research findings will be published in the prestigious journal ACS Nano. This work and a wide range of activities in related fields of nanoelectronics, photonics, and applications of ion beams was presented at the Advanced Technology Institute’s Open Day on Tuesday 18th December 2012, which marked the ATI’s 10th Anniversary. Details of the programme, and its presentations can be found at the ATI website soon.
The paper can be downloaded here.