Tag Archives: Ivan Parkin

Revolutionary ‘smart’ windows from the UK

This is the first time I’ve seen self-cleaning and temperature control features mentioned together with regard to a ‘smart’ window, which makes this very exciting news. From a Jan. 20, 2016 UK Engineering and Physical Sciences Research Council (EPSRC) press release (also on EurekAlert),

A revolutionary new type of smart window could cut window-cleaning costs in tall buildings while reducing heating bills and boosting worker productivity. Developed by University College London (UCL) with support from EPSRC, prototype samples confirm that the glass can deliver three key benefits:

Self-cleaning: The window is ultra-resistant to water, so rain hitting the outside forms spherical droplets that roll easily over the surface – picking up dirt, dust and other contaminants and carrying them away. This is due to the pencil-like, conical design of nanostructures engraved onto the glass, trapping air and ensuring only a tiny amount of water comes into contact with the surface. This is different from normal glass, where raindrops cling to the surface, slide down more slowly and leave marks behind.
Energy-saving: The glass is coated with a very thin (5-10nm) film of vanadium dioxide which during cold periods stops thermal radiation escaping and so prevents heat loss; during hot periods it prevents infrared radiation from the sun entering the building. Vanadium dioxide is a cheap and abundant material, combining with the thinness of the coating to offer real cost and sustainability advantages over silver/gold-based and other coatings used by current energy-saving windows.
Anti-glare: The design of the nanostructures also gives the windows the same anti-reflective properties found in the eyes of moths and other creatures that have evolved to hide from predators. It cuts the amount of light reflected internally in a room to less than 5 per cent – compared with the 20-30 per cent achieved by other prototype vanadium dioxide coated, energy-saving windows – with this reduction in ‘glare’ providing a big boost to occupant comfort.

This is the first time that a nanostructure has been combined with a thermochromic coating. The bio-inspired nanostructure amplifies the thermochromics properties of the coating and the net result is a self-cleaning, highly performing smart window, said Dr Ioannis Papakonstantinou of UCL.

The UCL team calculate that the windows could result in a reduction in heating bills of up to 40 per cent, with the precise amount in any particular case depending on the exact latitude of the building where they are incorporated. Windows made of the ground-breaking glass could be especially well-suited to use in high-rise office buildings.

Dr Ioannis Papakonstantinou of UCL, project leader, explains: It’s currently estimated that, because of the obvious difficulties involved, the cost of cleaning a skyscraper’s windows in its first 5 years is the same as the original cost of installing them. Our glass could drastically cut this expenditure, quite apart from the appeal of lower energy bills and improved occupant productivity thanks to less glare. As the trend in architecture continues towards the inclusion of more glass, it’s vital that windows are as low-maintenance as possible.

So, when can I buy these windows? (from the press release; Note: Links have been removed)

Discussions are now under way with UK glass manufacturers with a view to driving this new window concept towards commercialisation. The key is to develop ways of scaling up the nano-manufacturing methods that the UCL team have specially developed to produce the glass, as well as scaling up the vanadium dioxide coating process. Smart windows could begin to reach the market within around 3-5 years [emphasis mine], depending on the team’s success in securing industrial interest.

Dr Papakonstantinou says: We also hope to develop a ‘smart’ film that incorporates our nanostructures and can easily be added to conventional domestic, office, factory and other windows on a DIY [do-it-yourself] basis to deliver the triple benefit of lower energy use, less light reflection and self-cleaning, without significantly affecting aesthetics.

Professor Philip Nelson, Chief Executive of EPSRC said: This project is an example of how investing in excellent research drives innovation to produce tangible benefits. In this case the new technique could deliver both energy savings and cost reductions.

A 5-year European Research Council (ERC) starting grant (IntelGlazing) has been awarded to fabricate smart windows on a large scale and test them under realistic, outdoor environmental conditions.

The UCL team that developed the prototype smart window includes Mr Alaric Taylor, a PhD student in Dr Papakonstantinou’s group, and Professor Ivan Parkin from UCL’s Department of Chemistry.

I wish them good luck.

One last note, these new windows are the outcome of a 2.5 year EPSRC funded project: Biologically Inspired Nanostructures for Smart Windows with Antireflection and Self-Cleaning Properties, which ended in Sept.  2015.

Using quantum dots to detect and identify explosives

This research is courtesy of the University College London (UCL) according to a Dec. 9, 2015 news item on Nanowerk,

A new test for detecting multiple explosives simultaneously has been developed by UCL scientists. The proof-of-concept sensor is designed to quickly identify and quantify five commonly used explosives in solution to help track toxic contamination in waste water and improve the safety of public spaces.

Lead researcher, Dr William Peveler (UCL Chemistry), said: “This is the first time multiple explosives have been detected using a single sensor before, demonstrating proof-of-concept for this approach. Our sensor changes colour within 10 seconds to give information about how much and what explosives are present in a sample. Following further development, we hope it will be used to quickly analyse the nature of threats and inform tailored responses.”

A Dec. 9, 2015 UCL press release (also on EurekAlert), which originated the news item, expands on the theme,

Dr Peveler, added: “We analysed explosives which are commonly used for industrial and military purposes to create a useful tool for environmental and security monitoring. For example, DNT is a breakdown product from landmines, and RDX and PETN have been used in terror plots in recent years as they can be hard to detect using sniffer dogs. Our test can quickly identify these compounds so we see it having a variety of applications from monitoring the waste water of munitions factories and military ranges to finding evidence of illicit activities.”

The sensor is made of quantum dots, which are tiny light-emitting particles or nanomaterials, to which explosive targeting receptors are attached. As each explosive binds to the quantum dot, it quenches the light being emitted to a different degree. The distinct changes in colour are analysed computationally in a variety of conditions to give a unique fingerprint for each compound, allowing multiple explosives to be detected with a single test.

Senior author, Professor Ivan Parkin (UCL Chemistry), said: “Our sensor is a significant step forward for multiple explosives detection. Current methods can be laborious and require expensive equipment but our test is designed to be inexpensive, fast and use a much smaller volume of sample than previously possible. Although all of these factors are important, speed and accuracy are crucial when identifying explosive compounds.”

The team plan to take it from the laboratory into the field by blind testing it with contaminated waste water samples. They also hope to improve the sensitivity of the test by tailoring the surfaces of the quantum dots. Currently, its limit is less than one part per million which the team hope to increase into the part per billion range.

Here’s a link to and a citation for the paper,

Multichannel Detection and Differentiation of Explosives with a Quantum Dot Array by William J. Peveler, Alberto Roldan, Nathan Hollingsworth, Michael J. Porte‡, and Ivan P. Parkin. ACS Nano, Article ASAP DOI: 10.1021/acsnano.5b06433 Publication Date (Web): November 18, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall.