M o d u L e 2 : a p p L i c a t I o n s a n d I m p L i c a t I o n s

this module, Chapter 4: Information and Communication Technologies
.
NANOYOU DILEMMA The use of quantum dots in polymer composites for new forms of light-
emitting devices (QD-LEDs) is extremely promisingin the development of alternatives to 
conventional light bulbs. In the 
NANOYOU role-playing game ‘Revolution for the light bulb’ 
(http://www.nanoyou.eu/en/decide), students reflect on the safety aspects of these devices. Like 
other materials used in electronics (e.g. transistors), quantum dots are often made of toxic metals 
like cadmium, although in extremely small amounts. Therefore, QD-LEDs would need to be properly 
managed once disposed of, as is the case for all electronics, but even more so in this case. However, 
it is not yet known what method should be used to dispose of them, what sub-products could 
be produced, and if disposed of improperly, could they represent an environmental hazard. The 
dilemma is: Do we implement the quantum dot technology within an energy efficient light source 
even though some health and environmental risks remain unanswered?

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N A N O T E C H N O L O G I E S : P R I N C I P L E S , A P P L I C A T I O N S , I M P L I C A T I O N S A N D H A N D S - O N A C T I V I T I E S
Efficient energy transport
One area where there is a large margin for improvement is in the transport of electric current. As the 
world’s power demand increases, the burden on the electricity infrastructure grows. This has been 
shown recently in some nationwide blackouts such as those that occurred in the north-east USA in 
2003, and in Italy in the same year. Therefore, a major challenge is to develop new transmission-
line materials that are lighter and have less energy loss than copper. Single carbon nanotubes (CNT) 
have the remarkable property of weighing one sixth as much as copper but with similar or even bet-
ter conductivity and negligible eddy current loss. This material thus has the potential to overcome 
some of the limitations of current transmission materials. Before this can become a reality, however, 
advances in the production of CNTs are needed. At present, scientists produce CNTs often less than 
100 nm in length and with widely varying electrical conduction properties. The challenge for the future 
is, therefore, to produce nanotubes with controlled properties. Moreover, the manufacturing must be 
cost-effective and able to produce cables of fibres with the desired electrical properties. At present, 
therefore, this application remains a vision.