Nanoparticles show promise as an ingredient in solar cells, where they could absorb light and generate electrons. But photovoltaic devices made from nanoparticles are still far less efficient than conventional silicon cells. This is partly because some of the liberated electrons never reach an electrode. Now researchers at the University of Notre Dame in Indiana have doubled the efficiency with which these cells convert ultraviolet light to electricity. They deposited single-walled carbon nanotubes on an electrode to form a scaffold for electron-generating titanium dioxide particles. A carbon nanotube (cylindrical object, left) collects an electron (shown in pink) and provides a more direct route from the nanoparticles (round objects) to the electrode (right). The cells convert ultraviolet light to electrons more efficiently than commercial silicon cells, but they do not yet work with visible light.
Toronto wants to kill the smart city forever
The city wants to get right what Sidewalk Labs got so wrong.
Saudi Arabia plans to spend $1 billion a year discovering treatments to slow aging
The oil kingdom fears that its population is aging at an accelerated rate and hopes to test drugs to reverse the problem. First up might be the diabetes drug metformin.
Yann LeCun has a bold new vision for the future of AI
One of the godfathers of deep learning pulls together old ideas to sketch out a fresh path for AI, but raises as many questions as he answers.
The dark secret behind those cute AI-generated animal images
Google Brain has revealed its own image-making AI, called Imagen. But don't expect to see anything that isn't wholesome.
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