So many possibilities....
I'd be impressed with anything like these recent inventions.
Smart Phones, Laptops and Electric Vehicles
A coating for lithium-ion batteries that stabilises battery performance and increases the lifetime of the battery x 3. But it doesn’t prevent batteries from catching fire….
http://asq.org/qualitynews/qnt/execute/displaySetup?newsID=22989
Transport, building, clothing
A highly-durable, self-healing, water-repellent coating
https://www.rdmag.com/news/2017/04/new-chemical-coating-yields-durable-waterproofing-technique
Healthcare, Wastewater Treatment
A coating that chemically communicates with bacteria to either inhibit or promote their growth
https://www.eurekalert.org/pub_releases/2017-05/pues-ccb053017.php
Glass – Building and Solar Panels
A transparent, bioinspired, slippery coating which toughens glass and repels liquids and ice
http://news.harvard.edu/gazette/story/2013/08/new-coating-turns-ordinary-glass-into-superglass/
Defence and Medical Imaging
A nano carbontube coating which acts like an invisibility cloak
https://www.extremetech.com/extreme...make-very-stealthy-aircraft-better-telescopes
