Researchers at the Laboratory of Organic Electronics have discovered a material that can both increase and reduce its volume when exposed to a weak electrical pulse. In a sponge, or filter, the researchers can control the size of particles that pass through.
Materials, such as solids and gels, that change volume depending on temperature or pH have long been available. Such materials are used in control units (one example of which are windows in greenhouses that automatically open and close depending on the temperature). They are also used in robots and in other electromechanical systems and in applications in biomedicine. One property that researchers have, however, long sought is the change of a material from a solid form to a gel state with the aid of an electrical signal. It is particularly desirable that such electronic control of the phase transition is reversible. The goal is to be able to control the volume by electrical means. This is possible in current materials, but researchers have only been able to achieve at most a doubling of the volume.
A new material
Scientists at the Laboratory of Organic Electronics, Campus Norrköping, have now discovered a new material, a conducting polymer, that can increase its volume by a factor of more than 100. The material was synthesized in collaboration with researchers from Imperial College in London. The change takes place when the material is placed into an electrolyte and subjected to a weak electrical voltage of +0.8 V. If a negative voltage, -0.8 V, is instead applied, the material contracts, nearly the whole way back to its original volume.
This is a significantly larger volume change than those previously reported, not only in conducting polymers but also in other materials controlled by an electrical signal.
Experiments carried out by Johannes Gladisch and Eleni Stavrinidou have involved the conducting polymer being placed as a film with a thickness of a few micrometres around an electrically conducting carbon fibre.
When electrical pulses with magnitudes of +0.5 V or +0.8 V are applied, the material changes its internal structure, then absorbs water and is finally converted to a gel that expands to 14 or 120 times the original volume. When pulses of magnitude +/- 0.5 V are repeatedly applied, the material expands by approximately 300%, or to three times, with respect to its previous contracted state. The change in volume is reversible.
Changing the pores
The scientists also describe an application in the article, published in Advanced Science. This is a smart sponge, or filter, in which they can control the expansion electronically, and in this way change the pore size by 85%.
“We can control the pore size of a filter electronically, and potentially actively control the size of particles that pass through. This means that the properties of this smart filter can be dynamically changed to allow different types or different sizes of particle to pass through. This function can be used for sieving, filtration, purification, and in process chemistry. It may also have applications in medicine and biochemistry”, says Magnus Berggren, professor in organic electronics and director of the Laboratory of Organic Electronics.
The Latest on: Smart filter
via Google News
The Latest on: Smart filter
- Kim Komando: 6 Smart Ways to Manage Your Inbox and Email Overload on November 18, 2019 at 4:07 am
RELATED: Spam is probably your biggest email gripe. I hate it, too. Tap or click for easy ways to cut down on spam in your inbox. Spam filters help clean out the actual junk mail and phishing scams — ...
- Smart teams up with TikTok on November 17, 2019 at 8:22 am
Smart and TNT customers can now access TikTok with the new “GIGA Stories” offers ... The TikTok app’s diverse array of features includes a robust catalogue of copyrighted background music, filters and ...
- This air purifier will run forever without needing a filter change on November 15, 2019 at 12:13 am
The result is cleaner, fresher air without the necessary upkeep of having to replace activated charcoal chambers and clean out HEPA filters every couple of months. The puripot is capable of running ...
- At Pepcom Well Now!: Previewing Coway’s ‘Smart’ Mighty Air Purifier on November 14, 2019 at 4:00 pm
The new Mighty Air Purifier is a “smart” version of the earlier model ... It has a 300-foot purification range and comes with a HEPA filter. Its four-stage filtration system does pre-filtering, ...
- Global Smart Air Purifier Market 2025: Size, Industry Growth, Outlook and Analysis | Holmes Products, Coway, LG, Haier on November 14, 2019 at 3:19 am
primarily split into Plasma Wave Technology Carbon filter Others By Application, the market can be split into Commercial Used Household Used Get Full Report In Detailed At: ...
- Accruent Named an Industry Leader by Independent Analyst Firm in 2019 Internet of Things for Smart Buildings Green Quadrant on November 12, 2019 at 4:14 am
reducing downtime and emergency service costs Smart alarm management that filters out duplicate and non-critical alarms and resolves potentially critical alarms via persistent escalation procedures ...
- The 3 Best Faucet Water Filters on November 10, 2019 at 12:42 pm
Whether you're looking for a cost-effective and more environmentally friendly alternative to bottled water or just want to enhance the taste of your water and remove contaminants, it's smart to turn ...
- AirOk technologies launches new range of smart air purifiers on November 9, 2019 at 6:17 am
Smart air purifiers, these offer Wi-Fi & cloud connectivity, and users can also control the functions via a mobile app with ease. Vistar Comfort air purifiers demand low maintenance with filter ...
- IIT Madras start up launches range of Smart air purifiers on November 9, 2019 at 6:15 am
Smart air purifiers, these offer Wi-Fi & cloud connectivity, along with an area coverage between 15m2 to 104m2. IIT Madras incubated cleantech start-up, AirOk Technologies has launched its range of ...
- 4 clever ways smart tech can make your home safer on November 6, 2019 at 6:10 am
If you have smart devices powered by batteries, you can let Alexa keep track of them. The system will let you know when it’s almost time to replace low batteries or can order them for you from Amazon.
via Bing News