Smarter window materials can control light, energy

By allowing indoor occupants to more precisely control the energy and sunlight passing through a window, the new materials could significantly reduce costs for heating and cooling buildings.

In 2013, chemical engineering professor Delia Milliron and her team became the first to develop dual-band electrochromic materials that blend two materials with distinct optical properties for selective control of visible and heat-producing near-infrared light (NIR). In a 2013 issue of Nature, Milliron's research group demonstrated how, using a small jolt of electricity, a nanocrystal material could be switched back and forth, enabling independent control of light and energy.

The team now has engineered two new advancements in electrochromic materials -- a highly selective cool mode and a warm mode -- not thought possible several years ago.

The cool mode material is a major step toward a commercialized product because it enables control of 90 percent of NIR and 80 percent of the visible light from the sun and takes only minutes to switch between modes. The previously reported material could require hours.

To achieve this high performance, Milliron and a team, including Cockrell School postdoctoral researcher Jongwook Kim and collaborator Brett Helms of the Lawrence Berkeley National Lab, developed a new nanostructured architecture for electrochromic materials that allows for a cool mode to block near-infrared light while allowing the visible light to shine through. This could help reduce energy costs for cooling buildings and homes during the summer. The researchers reported the new architecture in Nano Letters on July 20.

"We believe our new architected nanocomposite could be seen as a model material, establishing the ideal design for a dual-band electrochromic material," Milliron said. "This material could be ideal for application as a smart electrochromic window for buildings."

New technology could help high-performance aircraft turbine engines stay cool, perform better

High-performance aircraft turbine engine manufacturers are facing unprecedented increases in the amount of heat that must be released in order to maintain acceptable temperatures in supersonic engines that is required for the aircraft to operate at optimum levels.

Issam Mudawar, professor in Purdue's School of Mechanical Engineering, has developed a device that could use aircraft fuel to cool hot engine components in order to alleviate the increasing temperatures.

Mudawar said hot engine components are generally cooled by air that is bled from the engine's compressor, but this type of system does not work for high-performance engines.

"Cooling an engine with air from the aircraft's compressor is not viable for high-performance engines since the compressor air at supersonic speeds is too hot itself," he said. "My technology uses the aircraft fuel to cool the compressor air before it is used to cool the hot engine components in the aircraft."

Mudawar said aircraft engine manufacturers could benefit greatly from the heat exchanger device.

Futuristic Jetpack Will Go on Sale for $200,000 Next Year

"It's a bird. It's a plane. It's a firefighter wearing a jetpack!" That could be something you find yourself saying as early as next year.

A company in New Zealand recently announced that its futuristic product — a fan-propelled, personal flying machine— will be commercially available during the second half of next year. But before you add the jetpack to your holiday wish list, check the price tag. It's expected to sell for around $200,000.

The pricey jetpack isn't just a toy for rich daredevils; it was designed with emergency first responders in mind, according to Martin Aircraft Co., which created this cool technology.