"My dream is that one day you'll have two technicians with Ghostbusters backpacks come to your house and spray your roof [with colloidal quantum dots].” —Illam Kramer

Solar Car Shade (from: Gizmag)

“Pretty soon, powering your tablet could be as simple as wrapping it in cling wrap. Scientists have just invented a new way to spray solar cells onto flexible surfaces using miniscule light-sensitive materials known as colloidal quantum dots (CQDs) -- a major step toward making spray-on solar cells easy and cheap to manufacture.
     [Illan Kramer] calls his system sprayLD, a play on the manufacturing process called ALD, short for atomic layer deposition, in which materials are laid down on a surface one atom-thickness at a time.
     Until now, it was only possible to incorporate light-sensitive CQDs onto surfaces through batch processing -- an inefficient, slow and expensive assembly-line approach to chemical coating. SprayLD blasts a liquid containing CQDs directly onto flexible surfaces, such as film or plastic, like printing a newspaper by applying ink onto a roll of paper. This roll-to-roll coating method makes incorporating solar cells into existing manufacturing processes much simpler. In two recent papers in the journals Advanced Materials and Applied Physics Letters, Kramer showed that the sprayLD method can be used on flexible materials without any major loss in solar-cell efficiency.
     Kramer built his sprayLD device using parts that are readily available and rather affordable -- he sourced a spray nozzle used in steel mills to cool steel with a fine mist of water, and a few regular air brushes from an art store.
     ‘This is something you can build in a Junkyard Wars fashion, which is basically how we did it,’ said Kramer. ‘We think of this as a no-compromise solution for shifting from batch processing to roll-to-roll.’”
— Science Daily
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“Solar power is often associated with solar cells on your roof, but here are many ways in which to exploit that never-ending energy of our little star. Artificial leaves have quite a lengthy history, here described with platinum catalysts, as used in labs in Colorado and California.
     The leaf has been more admired recently than ever before, by the chemists struggling to use sunlight energy to prepare hydrogen, oxygen or even electricity. The catalytic equivalent of chlorophyll, which promotes the conversions first of water into oxygen and then hydrogen into carbohydrate, is slowly being worked out. The photocatalyst is pasted onto a transparent indium tin oxide electrode to produce a semiconductor. […]
     The gases hydrogen and oxygen are given off. An artificial leaf is now being prepared to provide the much-vaunted hydrogen fuel that we have been going on about in the latest cars. […]
     The lower cost of their leaf means it can be converted into a full production module very soon, utilising solution synthesis and vacuum filtration. It is also free standing and needs no wiring up or external devices to increase costs. The attraction is the diversion of hydrogen production from the natural gas industry to an almost carbon –free production, using only solar energy.”
— Dave Armstrong, Earth Times
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