Subscribe to our free daily newsletters
  Energy News  




Subscribe to our free daily newsletters



ENERGY TECH
Ultra-fast and ultra-sensitive hydrogen sensor
by Staff Writers
Seoul, South Korea (SPX) Oct 05, 2017


Schematic illustration of a metal-organic framework (MOF). The MOF, consisting of metal ions and organic ligands, is a highly porous material with a ultrahigh surface area. The various structures of MOFs can be synthesized depending on the kinds of metal ions and organic ligands.

A KAIST team made an ultra-fast hydrogen sensor that can detect hydrogen gas levels under 1% in less than seven seconds. The sensor also can detect hundreds of parts per million levels of hydrogen gas within 60 seconds at room temperature.

A research group under Professor Il-Doo Kim in the Department of Materials Science and Engineering at KAIST, in collaboration with Professor Reginald M. Penner of the University of California-Irvine, has developed an ultra-fast hydrogen gas detection system based on a palladium (Pd) nanowire array coated with a metal-organic framework (MOF).

Hydrogen has been regarded as an eco-friendly next-generation energy source. However, it is a flammable gas that can explode even with a small spark. For safety, the lower explosion limit for hydrogen gas is 4 vol% so sensors should be able to detect the colorless and odorless hydrogen molecule quickly.

The importance of sensors capable of rapidly detecting colorless and odorless hydrogen gas has been emphasized in recent guidelines issued by the U.S. Department of Energy. According to the guidelines, hydrogen sensors should detect 1 vol% of hydrogen in air in less than 60 seconds for adequate response and recovery times.

To overcome the limitations of Pd-based hydrogen sensors, the research team introduced a MOF layer on top of a Pd nanowire array. Lithographically patterned Pd nanowires were simply overcoated with a Zn-based zeolite imidazole framework (ZIF-8) layer composed of Zn ions and organic ligands. ZIF-8 film is easily coated on Pd nanowires by simple dipping (for 2-6 hours) in a methanol solution including Zn (NO3)2-6H2O and 2-methylimidazole.

As synthesized ZIF-8 is a highly porous material composed of a number of micro-pores of 0.34 nm and 1.16 nm, hydrogen gas with a kinetic diameter of 0.289 nm can easily penetrate inside the ZIF-8 membrane, while large molecules (> 0.34 nm) are effectively screened by the MOF filter.

Thus, the ZIF-8 filter on the Pd nanowires allows the predominant penetration of hydrogen molecules, leading to the acceleration of Pd-based H2 sensors with a 20-fold faster recovery and response speed compared to pristine Pd nanowires at room temperature.

Professor Kim expects that the ultra-fast hydrogen sensor can be useful for the prevention of explosion accidents caused by the leakage of hydrogen gas. In addition, he expects that other harmful gases in the air can be accurately detected through effective nano-filtration by using of a variety of MOF layers.

This study was carried out by Ph.D. candidate Won-Tae Koo (first author), Professor Kim (co-corresponding author), and Professor Penner (co-corresponding author). The study has been published in the online edition of ACS Applied Materials and Interfaces, as the cover-featured image for the September issue.

Research paper

ENERGY TECH
Scientists harvest electricity from tears
Washington (UPI) Oct 1, 2017
Sad about the battery drain on your new smartphone? A good cry might help. Scientists have found a way to harvest electricity from tears. In recent lab experiments, researcher at the University of Limerick's Bernal Institute, in Ireland, found lysozyme crystals yield an electric current when pressurized. Lysozyme is found in tears and saliva, as well as the whites of bird eggs and the m ... read more

Related Links
The Korea Advanced Institute of Science and Technology
Powering The World in the 21st Century at Energy-Daily.com


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

ENERGY TECH
'Fuel-secure' steps in Washington counterintuitive, green group says

SLAC-led project will use AI to prevent or minimize electric grid failures

Scientists propose method to improve microgrid stability and reliability

ADB: New finance model needed for low-carbon shift in Asia

ENERGY TECH
Scientists harvest electricity from tears

Small scale energy harvesters show large scale impact

Research led by PPPL provides reassurance that heat flux will be manageable in ITER

Energy harvested from evaporation could power much of US, says study

ENERGY TECH
Germany gets economic lift with wind energy

French energy company to build wind power sector in India

Finding better wind energy potential with the new European Wind Atlas

Last of the 67 turbines for a British wind farm installed

ENERGY TECH
India gets lending support for a greener grid

Saudi Arabia opens bid for 'utility scale' solar project

DOE should take steps toward facilitating energy development on its public lands

Researchers set time limit for ultrafast perovskite solar cells

ENERGY TECH
Largest Nuclear Training Center In France Opens Its Doors

BWXT awarded contract extension for nuclear waste facility operations

UAE to open Arab Gulf's first nuclear reactor in 2018

Russia floats out powerful nuclear icebreaker

ENERGY TECH
Bioreactors on a chip renew promises for algal biofuels

Researchers develop 3-D-printed biomaterials that degrade on demand

Enzyme's worth to biofuels shown in latest NREL research

Algae with light switch

ENERGY TECH
Oil continues October drift lower

State taxes adding about a quarter to gas prices, U.S. government says

China, the world's top oil importer, rising to the top, investment firm reports

Russia proposes a mechanism to monitor crude oil exports

ENERGY TECH
Drought not dingos behind mainland Australia tiger extinction: study

Cost of climate disasters to reach half of US growth in a decade: report

Science denial not limited to political right

Canada Tory MP called out for referring to minister as 'climate Barbie'




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement