We’ve just been discussing extraordinarily reflective mirrors for advanced propulsion. Here’s the inverse, in a story from ScienceNOW:

Scientists have created the world’s first film that casts practically no reflection. A vast improvement over current nonreflective materials, the new technology could revolutionize solar cells, intensify light-emitting diodes, and possibly help solve mysteries in quantum mechanics by mimicking a “black body,” an object that absorbs all light.

The new coating reflects no light across much of the visual spectrum. This work, done at Rensselaer Polytechnic Institute, seems to have enormous potential for increasing solar cell efficiency. Much more here.