A million years ago when I was young, photosynthesis was one of the first “big words” I learned. And, unlike antidisestablishmentarianism, I even knew what it meant. Sorta. It was the way plants ate, right? How they turned sunlight and water into, uh, plant food? Yeah. I knew it was all very green and very complicated. But how complicated? I had no idea.
For years, scientists have been trying to understand how to reproduce photosynthesis artificially, which is the way plants produce energy from sunlight and water. A leaf does some incredible things with those two down-to-earth ingredients; most notably it makes sugars. What the folks in white coats reckon is if they can recreate the process, they might be able to divide water into its two main parts (hydrogen and oxygen). This is big science, and a big deal.
Hydrogen is one of best sources of energy we have that isn’t a fossil fuel. Unlike coal and oil, which emit carbon dioxide when burned (read: greenhouse gas), burning hydrogen releases only water vapor. Problem is, hydrogen don’t come easy and switching to what has been referred to as a “Hydrogen Economy” – featuring hydrogen-powered, cars and boats, electronics, buildings, everything – is going to take some serious work to get off the ground. Using sunlight (of which we have plenty) to get the sought-after hydrogen out of water would be a super sustainable way to feed our bottomless energy stomach without screwing up the environment any more than we already have.
So, back to the leaf.
An artificial one that could capture solar energy and use it to change water into hydrogen fuel would be smart. And here’s the news: Some of those white coats recently announced that they figured it out. At the 239th National Meeting of the American Chemical Society (ACS), held in March in San Francisco, a team offered their “recipe” for the “Artificial Inorganic Leaf,” which combines the action of a natural leaf with titanium dioxide (TiO2), a chemical already known as a photocatalyst for hydrogen production.
Complicated? Well, consider a) the team that created the new method: Tongxiang Fan, Ph.D., Di Zhang, Ph.D. and Han Zhou, Ph.D., representing the State Key Lab of Matrix Composites at Shanghai Jiaotong University in Shanghai, China., and b) the Rube Goldberg meets Paul Klee diagram below:
Says Fan: “Our results may represent an important first step towards the design of novel artificial solar energy transduction systems based on natural paradigms, particularly based on exploring and mimicking the structural design. Nature still has much to teach us, and human ingenuity can modify the principles of natural systems for enhanced utility.”
Our pals at Mother Nature Network translate this nicely: “In the end, an intriguing partnership between cutting-edge science and the most ancient of organic technologies – photosynthesis – may prove to have the real answer for powering a clean future.” There ya go, eh? Not so complicated, after all.
Image: linh.ngân