Hot electrons are, as their name suggests, hot. They possess a great amount of kinetic energy, though, making them desirable for capture in electricity generation. But they typically shed heat quickly and are effectively lost.
The BC researchers' panels are ultra-thin. By making solar cells thinner and smaller, they say, hot electrons may be captured more easily. Researcher Krzysztof Kempa, lead author of the paper on the new technology, compared the hot electron effect to that of a pot of boiling water. If the pot is dumped into a swimming pool, he said, its heat won't be felt at the pool's edges because the heat gets lost in the time it takes for the water to disperse. But a pot of boiling water poured into a sink of cold water will raise the temperature of the sink water because the sink is so much smaller.
The new cells are less than 30 nanometers thick, compromising their potential efficiency. But if combined with more-efficient light-trapping nanowires, the thin cells can be made viable for widespread use, researchers say.
