Ultra-Fast and Ultra-Sensitive Hydrogen Sensor
October 2, 2017 | KAISTEstimated reading time: 1 minute
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.
Suggested Items
Foxconn Pledges 100% Renewable Electricity by 2040, Joins RE100
04/22/2024 | FoxconnHon Hai Technology Group announced its worldwide operations will run fully on green electricity by 2040 and has joined the global initiative RE100, in a milestone on Earth Day 2024 that adds the world’s largest electronics manufacturer and technology solution provider among the most influential businesses committed to 100% renewable electricity.
Synaptics Astra AI-Native IoT Platform Launches with SL-Series Embedded Processors and Machina Foundation Series Development Kit
04/08/2024 | SynapticsSynaptics® Incorporated launched the Synaptics Astra platform with the SL-Series of embedded AI-native Internet of Things (IoT) processors and the Astra MachinaTM Foundation Series development kit.
Canon Taiwan Earns IPC J-STD-001 and IPC-A-610 Qualified Manufacturer’s Listing
04/04/2024 | IPCIPC’s Validation Services Program has awarded an IPC Qualified Manufacturers Listing (QML) to Canon Taiwan, a leader in the optical industry, producing single-lens reflex/mirrorless digital cameras, camera lenses, accessories and network surveillance monitors.
indie Semiconductor Announces Strategic Investment in AI Processor Leader Expedera
04/03/2024 | indie Semiconductorindie Semiconductor, Inc., an Autotech solutions innovator, announced a strategic investment in Expedera Inc, a leading provider of scalable Neural Processing Unit (NPU) semiconductor intellectual property (IP).
Kimball Electronics Publishes Annual Sustainability Disclosures with its 2023 Guiding Principles Report
03/28/2024 | BUSINESS WIREKimball Electronics, Inc. published its annual sustainability disclosures in its 2023 Guiding Principles Report, themed “How We Are Winning Together The Kimball Way.”