My Thoughts on Technology and Jamaica: How Dr. Chunlei Guo's of University of Rochester makes Hydrophobic Metal Surfaces using Lasers

Sunday, January 25, 2015

How Dr. Chunlei Guo's of University of Rochester makes Hydrophobic Metal Surfaces using Lasers

Captain America, AntMan and Mr. Atom fans all over the world will finds this bit of News very exciting. Queue the movie Trailer for Captain American, The Winter Soldier.


Researchers at the University of Rochester have developed a way to make Metal hydrophobic by tracing a pattern at the nanoscopic level using a Laser as reported in the article “Laser-generated surface structures create extremely water-repellent metals”, published Jan 20, 2015, Physorg.

Their research, published in the Journal of Applied Physics, was led by Dr. Chunlei Guo and his colleague at the University's Institute of Optics, Anatoliy Vorobyev involving the use of Femtosecond Lasers to carve intricate patterns on the Metal surface.


Yes, in case you're a fan of my blog My Thoughts on Technology and Jamaica these past years, these are the same Femtosecond Lasers used in Research done by Dr. Jingyu Zhang at the University of Southampton's Optoelectronics Research Center and Eindhoven's University of Technology to write Data to naturally occurring Quartz Crystal back in July 2013 as chronicled in my blog article entitled “University of Southampton and Eindhoven's University write and read Data to Quartz Crystal - Eternal Storage borrowed from Superman Man of Steel”.

FemtoLaser, more correctly called Femtosecond Lasers, are Lasers that pulse rapidly on and off with a period of 1x10−15 seconds or a frequency of 1000 THz. According to their Research, during each pulse the amount of energy release per pulse is equivalent to the power requirements of the entire US of A, yet it’s powered from a Wall socket.

So how does this Femtosecond Lasers makes Metal and potentially any surface have these properties? Apparently a capacitor is involved, as I’ll explain later.

Dr. Chunlei Guo Patterns on a Metal – Making Music on the Surface at a Nanoscopic Level

This super powerful yet apparently portable Laser is used to blast out a pattern on the surface of the Metal that looks like quilted Downy Toilet Paper, making the surface ultra-smooth and flat, with few large nanoscopic mountains on the surface as shown below, only gentle rolling hills at least 20 to 50 Atoms across.



The resulting pattern on the Metal becomes a permanent part of the Metal’s surface, unlike coating like Liquipel that merely coats a given surface with a hydrophobic organic polymer as noted in my blog article entitled “Waterproof and Water-Resistant with Liquipel 2.0 – How to make your smartphone Water-Resistant to even Toilet Water”.

In fact, the surface is so hydrophobic that water literally bounces off the surface, collecting dust particles as it rolls around, making such a surface easier to clean and impossible to get dirty.

Even more impressive is that the angle at which water will roll off such a surface is only 5°.
This is much lower than the 70° angle required to make water roll of a source coated with PTFE (Polytetrafluoroethylene) commercially known as Teflon and the substance used to coat non-stick Metal or Ceramic Frying pots.

Best of all, it doesn’t rust!

University of Rochester and Hydrophobic Metal – Mr. Atom becomes an Architect at the Nanoscopic scale

Strange as it may seem, scratching an intricate, precise pattern on a metallic surface using a high precision Femtosecond Lasers imparts incredible properties to the Metal.

This shouldn't come as a surprise as if the Laser is a powerful as advertised in the Journal, at that power level it can create Quantum Dots of Metals on the surface of the Metal at an atomic scale.

Effectively, this is the equivalent of dropping atomic bombs on the surface of the Metal to move mountains of Atoms to create intricately precise machined structures.



Another way to look at it is that it’s no different from someone shrinking down to the size of an Atom, like Mr. Atom. Then that person or Team of Atom sized individuals, armed with pickaxes, shovels or better yet a Caterpillar backhoe and other earth moving equiptment like dynamite and pneumatic drills at that nanoscopic level, would dig into the Metal surface.

Using those theoretical nanoscopic tools along with other miniature tools, these Atomic sized miners can move and pile the Atoms into intricate patterns that in turn, impart properties to the metallic surface. Best of all, because it’s at a nanoscopic scale using the Atoms from the surface of the Metal, these changes are a permanent part of the metallic surface, imparting, as I said, different properties to the metallic surface.



If my theoretical miners at the Atomic scale were to dig up Atoms on the metals surface and pile the Metal Atoms into slanting vertical columns that resulted in photons begin reflected back down to the surface of the Metal, they could create internal reflection.

Such structures could be channels with covered archways that had small slit-like openings or even skyscrapers with very smooth reflective surfaces.  What would happen is that photons of light reaching such a nano-sculpted surface would continuously reflect light back down to the metallic “surface”, making it appear permanently black.

This is what Dr. Chunlei Guo’s Research Team at the University of Rochester did back in November 2006 using a Femtosecond Lasers to create a surface that absorbs light, actually reflecting and refracting it on the surface so well that it's permanent black, as noted in the article “Ultra-intense Laser blast creates true 'black Metal'”, published Nov 21, 2006, Physorg.

To quote Dr. Chunlei Guo in his own words back then, quote: “We've been surprised by the number of possible applications for this. We wanted to see what would happen to a Metal's properties under different Laser conditions and we stumbled on this way to completely alter the reflective properties of metals”.

Similarly, if our atomic Miners were to dig up Atoms on the surface of the Metal and make little parallel trenches at least 20 Atoms and separated by walls at least 40 Atoms wide going in one direction, this system of canal ways would basically be a nano-capillary system.



Using Van Der Waal's forces of attraction at the Nanoscopic scale to attract liquid, making it possible to overcome the liquids Atoms own internal covalent and Van Der Waal forces of attraction and causing it to climb up any surface.

This is what Dr. Chunlei Guo’s Research Team at the University of Rochester did back in June 2009 using as Femtosecond Lasers to create a surface that can attract water and make it go uphill  as reported in the article entitled “Scientists create Metal that pumps liquid uphill”, published Jun3 02, 2009, Physorg.



This would be the opposite of the surface that is hydrophobic; Dr. Chunlei Guo’s Research Team effectively created a hydrophilic surface that attracts water and make it go upwards, against the force of gravity in a manner very similar to the Leidenfrost Effect, but sans grooves and heated surfaces.

Again, to quote Dr. Chunlei Guo own words back then, quote: “Imagine a huge waterway system shrunk down onto a tiny chip, like the electronic circuit printed on a microprocessor, so we can perform chemical or biological work with a tiny bit of liquid. Blood could precisely travel along a certain path to a sensor for disease diagnostics. With such a tiny system, a nurse wouldn't need to draw a whole tube of blood for a test. A scratch on the skin might contain more than enough cells for a micro-analysis”.

Nanoscopic Patterns on Atomic Scale – Everything is possible with the Art of the Laser

Different patterns on the surface of the Metal create different properties, no different from etching a Processor in as Fabrication Lab at Intel. The different here is that the fabrication process is done using a high-energy Laser that puts out as much every per femtosecond as the US of A in a single blast in an area about as small as the point of a needle on a Metal surface.

This is possible thanks to using a high capacity Capacitor that stores energy and discharges in rapid bursts to power the Femtosecond Lasers, scorching and moving the reshaping the landscape at a nanoscopic scale, Atom by Atom. And as this technique has been done for years on semiconductor silicon using chemical and UV Light, so too can Femtosecond Lasers be used on other materials other than Metal.

Just be prepared to wait 1 hour to do a piece of Metal surface 1 inch square.

The University of Rochester’s Team is working on a way to speed up the process and scale it up to as manufacturing process, making it possible to build surfaces with different properties based on the type of patterns that coat the surface. Even secret messages can be store on to the surfaces, invisible to the naked eye.

But according to Dr. Chunlei Guo, the possibilities are endless in terms of the properties that can be imparted to the surface based on the pattern as well as the resolution of the nanoscopic manipulation of the material:

1.      Surfaces that are Hydrophobic and Hydrophilic   
2.      Surfaces that can reflect and absorb light
3.      Surface that are effectively invisible like the Harry Potters Invisibility cloak
4.      Surfaces that can reflect or absorb sound e.g. like Captain America’s Vibranium shield
5.      Surfaces covered with data, effectively an eternal storage media with infinite capacity

I'm pretty excited about this, as it has immediate applications for the Developing World, to quote Dr. Chunlei Guo: “In these regions, collecting rain water is vital and using super-hydrophobic materials could increase the efficiency without the need to use large funnels with high-pitched angles to prevent water from sticking to the surface. A second application could be creating latrines that are cleaner and healthier to use”.

It also means I can finally get a non-stick Metal or Ceramic pot in the future that won’t scratch off and will be permanently non-stick, great for cooking my favoiurtie meal of Ramen noodles as described in my blog article entitled “Cooking Restart at MICO - How to Cook a Meal in under 30 minutes and make Drinks with Bag Juice”!

Just kidding, but at least it woundn’t rust so fast, thanks to this clever yet innovative discovery by Dr. Chunlei Guo and his colleague at the University's Institute of Optics, Anatoliy Vorobyev!


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