Home > Press > IBS team detects hot electrons in real time: The Center for Nanomaterials and Chemical Reactions fabricated a graphene-semiconductor catalytic nanodiode for improved conductivity of graphene-based nanostructures
Schottky junction between a single layer of graphene and an n-type TiO2 layer lowered potential barrier existing at the Pt NPs/graphene interface, allowing the detection of hot electron flows produced during H2O formation. CREDIT: IBS |
Abstract:
From converting vehicle exhaust fumes into less harmful gases to refining petroleum, most commercial chemical applications require nanocatalysts since they can reduce the required time and costs by controlling the rate of chemical reactions. The catalytic activity and selectivity largely depends on their physical properties (size, shape, and composition) as well as the electronic characteristics; the dynamics of hot (high energy) electrons on the surface and interface of catalysts. Though the catalyst industry is constantly growing, it's challenging to permit electric currents to nanocatalysts in order to detect hot electrons and measure the catalytic efficiency.
In a new study, the Institute for Basic Science (IBS) team working under the Center's group leader, Professor PARK Jeong Young, created a catalytic nanodiode composed of a single layer of graphene and titanium film (TiO2) that enabled the detection of hot electrons on platinum nanoparticles (Pt NPs). This breakthrough research developed a catalytic nanodiode that allowed the team to observe in real time the flow of hot electrons generated by chemical reactions. Since hot electrons are created when excess energy from the surface of a chemical reaction is permitted to dissipate in femtosecond, they are deemed as an indicator for the catalystic activity. However, the quick thermalization of hot electrons makes the direct detection of hot electrons quite difficult for clarifying the electronic effect on catalytic activity on metal nanoparticles. In this study, researchers extracted 'hot carriers' from a metal catalyst using a graphene-semiconductor junction.
A new approach
The scientific team experiments differed to previous attempts where gold was used which proved to be inefficient, unstable and expensive. The team from the Center for Nanomaterials and Chemical Reactions experimented on a single layer of graphene, grown on a copper film before being transported to TiO2 where Pt NPs were later deposited. Graphene, the 2D wonder material, was used because of its unique electronic and chemical properties. When integrated with metal NPs, tremendous improvements in the conductivity performance between the supporting material and the platinum NPs were observed by the team. The catalytic activity and amount of hot electrons were measured; the results showed that the catalytic activity and the generation of hot electrons are well-matched and the reaction mechanism can be studied with hot electrons dynamic. "Graphene-based nanostructures, such as ours are promising detectors for the study of hot electron dynamics on metal NPs during the course of catalytic reactions" confirmed the team's paper.
The team's work, according to their paper, highlights the lowered contact resistance at the Pt NPs/ graphene interface is the main characteristic leading to efficient hot electron detection on the nanocatalysts in the graphene- based catalytic nanodiode. By utilizing a single layer of graphene for electrical connection of the Pt NPs it allowed for easier observation of hot electrons because of both the atomically thin nature of graphene and the reduced height of the potential barrier existing at the Pt NPs/ graphene interface. The research conducted at IBS can, potentially, help design catalytic and energy materials with improved performances and lower costs. First author and Ph.D. student Hyosun LEE stated: "Even though there is still the potential for improving the quality of the graphene layer itself and its contact with the TiO2, the approach presented here offers a new way to study the roles of graphene during heterogeneous catalysis."
####
For more information, please click here
Contacts:
Dahee Carol Kim
82-428-788-133
Copyright © Institute for Basic Science
If you have a comment, please Contact us.Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
Related Links |
Related News Press |
News and information
Simulating magnetization in a Heisenberg quantum spin chain April 5th, 2024
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Chemistry
What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024
Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024
Graphene/ Graphite
NRL discovers two-dimensional waveguides February 16th, 2024
Discoveries
Chemical reactions can scramble quantum information as well as black holes April 5th, 2024
New micromaterial releases nanoparticles that selectively destroy cancer cells April 5th, 2024
Utilizing palladium for addressing contact issues of buried oxide thin film transistors April 5th, 2024
Materials/Metamaterials/Magnetoresistance
Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024
Focused ion beam technology: A single tool for a wide range of applications January 12th, 2024
Announcements
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters
Simulating magnetization in a Heisenberg quantum spin chain April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Energy
Development of zinc oxide nanopagoda array photoelectrode: photoelectrochemical water-splitting hydrogen production January 12th, 2024
Shedding light on unique conduction mechanisms in a new type of perovskite oxide November 17th, 2023
Inverted perovskite solar cell breaks 25% efficiency record: Researchers improve cell efficiency using a combination of molecules to address different November 17th, 2023
The efficient perovskite cells with a structured anti-reflective layer – another step towards commercialization on a wider scale October 6th, 2023
Automotive/Transportation
Researchers’ approach may protect quantum computers from attacks March 8th, 2024
Tests find no free-standing nanotubes released from tire tread wear September 8th, 2023
The latest news from around the world, FREE | ||
Premium Products | ||
Only the news you want to read!
Learn More |
||
Full-service, expert consulting
Learn More |
||