This Cool-as-Hell, Lung-Inspired Design Can Turn Water Into Fuel

Who knew breathing was so inspiring? 

Breathing may seem pretty simple and natural to us, but to chemical engineers in particular, the mammalian act of breathing in oxygen and breathing out carbon dioxide is still considered somewhat of a marvel. Scientists would love to figure out a way to reverse the process, that is, to suck in carbon dioxide and convert it into something useful life fuel. That’s why a new lung-inspired mechanical design that turns water into fuel could be such a boon for the clean energy industry.

Researchers from Stanford University announced yesterday that they’d designed an electrocatalyst - material that modifies and increases chemical reactions without being consumed in the process - that mimics the same two-way gas exchange our bodies perform tens of thousands of times every day. Their design, published in the journal Joule, draws on the unique structure of the lung’s alveoli to split water into hydrogen and oxygen molecules - and then re-use the oxygen molecules as fuel for the catalyst.

Who knew breathing was so inspirational? 

Okay, remember ninth grade biology? Alveoli are the tiny air sacs that sit at the end of our respiratory system. Just one cell thick, alveoli allow for oxygen we inhale to diffuse through them and into the bloodstream; at the same time, carbon dioxide, a byproduct of cellular respiration, flows back through the alveoli and is then ultimately exhaled. Scientists at Stanford University, led by Yi Cui, incorporated an alveolus-like, ultra thin membrane made from polyethylene into their design to help with the simultaneous gas exchange. Who knew breathing could be so inspiring?

The hope that we could use “water as fuel” has circulated throughout the clean energy community for several years now. But the problem has always been a lack of efficiency. The energy needed to split hydrogen and oxygen was greater than the amount of energy ultimately generated. With this new lung-inspired design, oxygen is split from hydrogen and then used to fuel as continually power the mechanism. It’s all kept within the same system. And it’s cool as hell.

Though the design is still in a testing phase and not yet ready for commercial use, Yi Cui and his team hope their electrocatalyst will prove helpful for existing technologies, like fuel cells, which run as long as they have access to fuel and oxygen (And now water! Which could be that fuel!). They also think the tech could be useful for developing metal-air batteries.

It’s not clear whether large-scale adoption of this lung design could, oh, I don’t know, make use of the rising bodies of water threatening to sink, like, the entire east coast, but hey - one can always hope.