Featured Research

from universities, journals, and other organizations

Sensors detect contaminants in water in low concentrations

Date:
June 6, 2012
Source:
University of Notre Dame
Summary:
Many organic contaminants in the air and in drinking water need to be detected at very low-level concentrations. New research could be beneficial in detecting those contaminants.

Electron hopping.
Credit: Kamat laboratory

Many organic contaminants in the air and in drinking water need to be detected at very low-level concentrations. Research published by the laboratory of Prashant V. Kamat, the John A. Zahm Professor of Science at the University of Notre Dame, could be beneficial in detecting those contaminants.

Related Articles


The Kamat laboratory uses Surface-Enhanced Raman Spectroscopy to make use of silver nanoparticles to increase the sensitivity limit of chemical detection. Researchers in this study have prepared a semiconductor-graphene-metal film that has distinct advantages: The absorption of organic molecules on the film's graphene surface increases the local contaminant concentration adjacent to silver nanoparticles.

The researchers have investigated the use of graphene oxide films in which the semiconductor titanium dioxide (TiO2) and metal nanoparticles are deposited on opposite sides of the graphene surface. "We are currently working toward the detection of environmental contaminants at even lower levels," Kamat says. "Careful control of metal size and loading will be the key to optimize strips for testing water quality."

Under UV illumination, the electrons from TiO2 are captured by the graphene oxide film and shuttled across the film to reduce metal ions into metal nanoparticles. This electron-hopping process across the graphene oxide film allows the design of a side-separated semiconductor-metal nanoparticle architecture.

Graphene, a two-dimensional crystalline form of carbon, is known for its remarkable mechanical strength, very high thermal and electrical conductivity and broad variety of applications. While the conducting properties of graphene sheets deposited on various substrates are well understood, the Kamat group has demonstrated that the transport of electrons is not limited to the 2-D plane. Here, the hopping of electrons from one side of the graphene allows for the side-selective deposition of silver nanoparticles.

"Another potential application is in the area of photocatalytic generation of solar fuels," Kamat says. "For example, having semiconductor nanoparticles on one side of a graphene sheet and a metal catalyst on the other side, one can create a hybrid assembly that can selectively split water into oxygen and hydrogen."

The research was supported by the Office of Basic Energy Sciences, Department of Energy.


Story Source:

The above story is based on materials provided by University of Notre Dame. Note: Materials may be edited for content and length.


Journal Reference:

  1. Ian V. Lightcap, Sean Murphy, Timothy Schumer, Prashant V. Kamat. Electron Hopping Through Single-to-Few-Layer Graphene Oxide Films. Side-Selective Photocatalytic Deposition of Metal Nanoparticles. The Journal of Physical Chemistry Letters, 2012; 1453 DOI: 10.1021/jz3004206

Cite This Page:

University of Notre Dame. "Sensors detect contaminants in water in low concentrations." ScienceDaily. ScienceDaily, 6 June 2012. <www.sciencedaily.com/releases/2012/06/120606155806.htm>.
University of Notre Dame. (2012, June 6). Sensors detect contaminants in water in low concentrations. ScienceDaily. Retrieved March 27, 2015 from www.sciencedaily.com/releases/2012/06/120606155806.htm
University of Notre Dame. "Sensors detect contaminants in water in low concentrations." ScienceDaily. www.sciencedaily.com/releases/2012/06/120606155806.htm (accessed March 27, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Friday, March 27, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Amazon Complains U.S. Is Too Slow To Regulate Drones

Amazon Complains U.S. Is Too Slow To Regulate Drones

Newsy (Mar. 25, 2015) Days after getting approval to test certain commercial drones, Amazon says the Federal Aviation Administration is dragging its feet on the matter. Video provided by Newsy
Powered by NewsLook.com
Smartphone Use Changing Our Brain and Thumb Interaction, Say Researchers

Smartphone Use Changing Our Brain and Thumb Interaction, Say Researchers

Reuters - Innovations Video Online (Mar. 25, 2015) European researchers say our smartphone use offers scientists an ideal testing ground for human brain plasticity. Dr Ako Ghosh&apos;s team discovered that the brains and thumbs of smartphone users interact differently from those who use old-fashioned handsets. Jim Drury went to meet him. Video provided by Reuters
Powered by NewsLook.com
China Wants to Export Its Steel Problem

China Wants to Export Its Steel Problem

Reuters - Business Video Online (Mar. 25, 2015) China is facing a crisis with a glut of steel and growing public anger over the pollution created by production. In a move to solve the problem, some steel mills are looking to relocate overseas. Jane Lanhee Lee reports. Video provided by Reuters
Powered by NewsLook.com
Robot Stays on Its Feet Despite Punishment

Robot Stays on Its Feet Despite Punishment

Reuters - Innovations Video Online (Mar. 24, 2015) Robotic engineers have modelled a two-legged robot to be fast and agile like an ostrich. The design is more efficient and stable than bipedal robots built to move like humans, according to its creators who abuse the poor machine to test its skills. Ben Gruber has more. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins