That is all very well but what happens to the plants that require CO2 to grow if they reduce the amount of that plant food in the atmosphere?
Since there has been an increase of CO2 in the atmosphere there has been a corresponding increase in the amount of plant ground cover all over the world as well as an increase in plant based food production. Do these people really want to roll that back?

" if the researchers were to scale up their operation to cover a physical area less than 10 percent the size of the Sahara Desert, it would be enough to cut the concentration of carbon dioxide in the atmosphere to pre-industrial levels within 10 years."
10% of Sahara Desert surface area = 9,40,000 square kilometres
"We are scaling up quickly," says Licht. “And soon should be in range of making tens of grams (0.04 oz) of nanofibers an hour."
tens of grams an hour - Wow that'll save the world from impending doom !!!
In the last 30yrs CO2 fertilisation correlated with an 11 per cent increase in foliage cover across parts of the arid areas studied in Australia, North America, the Middle East and Africa, See- http://www.csiro.au/Portals/Media/Deserts-greening-from-rising-CO2.aspx.

how about using this process on every factory output? coal powered plants?

Seems to be some very dodgy statements here. Tens of grammes do not equate to hundredths of an ounce (25.4 gms. to the ounce). The process only needs 1 volt - maybe so but that is not a measure of energy, one needs to know the amperage as well to begin to get an idea of the energy requirement. " is much less than the 3 to 5 volts used in the 1,000° C industrial formation of aluminium" - our local Al smelter was powered by it's own dedicated power station!! Heating "carbonates" to 750 C cannot be an insignificant consumer of energy, and even if were possible to use solar cells, think of all the materials and energy used in their manufacture. And then there is the carbon footprint of obtaining all the "carbonate", not to mention that of transporting all this to the Sahara and constructing the plant. All seems a bit tenuous. I did check the calendar in case today was 1st. April.

Go away naysayers, it is a true statement that whenever anyone raises the possibility of something positive being achieved for anything, up pop the 'no you cant' people, whose chief joy in life is to stamp on anything great ! Nothing was ever achieved by those same people of course, they are miserable! So - I am very excited at this news and wish the world to get on board and start helping with the start-up of a large scale test plant. If I had the money I would start one myself. What about a Kickstarter campaign for that ? As far as I am concerned the temperature increases are about as high as we can bear to go, we may have increased vegetation which is great, if so let's keep it at about this same level, if we can get going with mitigation we can limit the amount of CO2 to whatever makes sense. By which time we will probably have a huge stack of nanofiber waiking around to be used anyway !!! Thanks for some good news and congratulations on this discovery - I have been saying for years 'why cant we just make something with the CO2?'. !!!!

You wouldn't have to build this in the Sahara, and you wouldn't necessarily have to build it as one big facility. You could build smaller "factories" and spread them around the world. I have no idea as to the actual numbers relating to power consumption and output of product, but if this is feasible, then it might not need to be run as a profit making operation, but as away to possibly save the planet.

Here we go again with the "the CO2 is rising and the sky is falling" routine. Face it. Plant life loves CO2. Another genius idea: let's suck CO2 out of the atmosphere (that plants need) and make it into carbon nanofibers which eventually will contaminate the planet. Has anyone thought about what is going to happen when all of these nanoparticles and fibers will be released into our environment? Since they're so small there will be no way to clean or filter them out. Imagine what they will do to plant and animal life (and us).

How much heat will be released into the environment by such a factory? People are being infested with a belief that science and technology can always arrive in time to save us and frankly that is a foolish belief. We need to scale down the size of society and all its trappings in order to survive.

I am not too worried about too little CO2. Note that the claim is about a space 1/10 the size of the Sahara desert. That's TWO Californias! It's not going to happen at that scale. Say instead we used a space the size of Rhode Island? Mitigates a lot of CO2 emissions (but probably not all), and provides a valuable feedstock for industry at a relatively low cost. The original abstract says they're modeling out an energy cost of about $1,000 per ton. Not sure of the accounting here, but if it's in the ballpark (i.e., not out by more than an order of magnitude), that probably means much cheaper carbon nanofiber than other ways to get it.
Also, just for a reference point, globally we use about one million metric tonnes of wood materials for construction annually. Of course, that pales in comparison to the amount of steel used in construction, which is about 500 million metric tonnes. Cheap carbon fiber-based materials are potential replacements for both of these uses.

Great as long as it doesn't let CO2 producers off the hook to produce more CO2. Can it recycle carbon filters?