Better Solar Cells with Diatoms

Let’s start with the operative quote before the subject matter: “Nature is the engineer, not high tech tools.  This is providing a more efficient, less costly way to produce some of the most advanced materials in the world.”  OK, now the subject: how to build better solar cells, by imitating diatoms.  See the story on Science Daily.
    The tiny pores in the silica tests (cases) of diatoms are very efficient at scattering light.  “These tiny, single-celled marine life forms have existed for at least 100 million years and are the basis for much of the life in the oceans,” the article said, assuming the evolutionary timeline, “but they also have rigid shells that can be used to create order in a natural way at the extraordinarily small level of nanotechnology.”
    Researchers at Oregon State (OSU) have found a way to not just imitate the diatoms, but actually incorporate them.  “The new system is based on living diatoms, which are extremely small, single-celled algae, which already have shells with the nanostructure that is needed,” the press release says.  “They are allowed to settle on a transparent conductive glass surface, and then the living organic material is removed, leaving behind the tiny skeletons of the diatoms to form a template.”  Presto: a solar cell with better efficiency than those hard-to-manufacture ones.  It’s cheaper, easier, and better: “Steps that had been difficult to accomplish with conventional methods have been made easy through the use of these natural biological systems, using simple and inexpensive materials” that are already available in abundance.
    The researchers don’t even understand the physics.  They just know it works: “the tiny holes in diatom shells appear to increase the interaction between photons and the dye to promote the conversion of light to electricity, and improve energy production in the process.”
    That’s good news to a world looking for green ways to extract energy from renewable resources.

The evolutionary timeline and historical fluff was really unnecessary.  It just added a little humor here and there to a serious – and wonderful – application of biomimetic research.  Nothing in biomimetics makes sense except in the light of design.