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Deserts are not particularly welcoming environments,
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and yet at least hundred million people live in desert regions around the world, according to the UN.
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They have to make due with less than 25 cm of rainfall each year,
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and for many, even that miniscule water supply is under threat as climate change is making dry areas even drier.
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So scientists at UC Berkeley have been experimenting with materials that can pull drinking water out of thin air.
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The compound they've devised is one of a family of materials called Metal-Organic-Frameworks, or MOFs.
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MOFs are, well it's pretty much right in the name, frameworks of metal atoms
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connected to each other with organic linkers.
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This structure makes them porous like a sponge,
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giving them incredible surface areas; a single gram of a MOF can have
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the surface area of a football field.
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And depending on the metal and organic molecules they're made of,
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they can be tailored to capture different things in their pores.
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MOFs have potential uses capturing CO2 and turning it into the fuel methanol,
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or neutralizing nerve agents like sarin gas.
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The function the Berkeley scientists tuned their MOF for was extracting water vapor that's present in the air.
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The first one they made in 2014, called MOF-801, was zirconium based.
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When tested in a water harvester it worked entirely passively,
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absorbing and condensing water overnight and giving it up again when the sun warmed it up.
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So the concept worked, and used a lot less energy than the other way of extracting water from low humidity air,
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which involves cooling the air below freezing.
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But Zirconium is expensive, so the scientists set to developing MOF-303
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based on the much cheaper element aluminum.
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Not only is the new MOF cheaper, it also performs much better.
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It can hold 30% more water and fill up and empty in just 20 minutes in the right conditions.
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And because the MOF was designed to leave no traces of organic or inorganic material in the water,
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it's completely pure and drinkable right away.
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Using the same passive technique in a harvester left overnight in the Arizona desert,
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one kilogram of MOF-303 harvested 0.2 liters of water.
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Now I know what you're thinking. That doesn't sound like a lot of water. And you're right.
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But the good news is the aluminum based MOF's ability to fill and empty in minutes can be exploited.
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The scientists changed up their design.
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Instead of passively relying on a day night cycle, their latest harvester relies on solar powered fans
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and heaters to run dozens of cycles a day.
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Ideally it can make more than 1.3 liters of water per kilogram of MOF each day,
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and the researchers hope to get that number as high as 8 or 10 liters per kilogram.
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The lead researcher behind this has started a private company called Water Harvesting.
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The plan is to launch a microwaved sized device that can supply 2 adults with enough drinking water
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for their daily hydration and cooking needs.
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Eventually they envision a harvester big enough to supply a small village.
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If the devices are affordable, safe, and reliable enough,
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these metal-organic frameworks have the potential to turn even the driest deserts into oases.
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Clean drinking water has always been a challenge for humanity, and sometimes we make mistakes.
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Like when we decided lead pipes were a good idea.
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Thankfully, researchers are developing ways to render the poisonous pipes harmless.
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Amanda has more here.
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If you liked this video let us know in the comments, and don't forget to subscribe.
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Thanks for watching and I'll see you next time on Seeker.