LIBS analysis of lead and cadmium in a water jet is fast and sensitive

April 1, 2011
Fast and effective detection of lead (Pb) and cadmium (Cd) metals in water is the goal of M. Sadegh Cheri and S.H. Tavassoli of Shahid Beheshti University (Tehran, Iran); they have created a laser-induced-breakdown spectroscopy (LIBS) system relying on a laminar water jet to eliminate problems of splashing.

Fast and effective detection of lead (Pb) and cadmium (Cd) metals in water is the goal of M. Sadegh Cheri and S.H. Tavassoli of Shahid Beheshti University (Tehran, Iran); they have created a laser-induced-breakdown spectroscopy (LIBS) system relying on a laminar water jet to eliminate problems of splashing. Because the water position is well known, only small amounts of liquid are vaporized and the repeatability is improved. As a result, the researchers found that the limit of detection (LOD) for Pb was three times better than for other studies.

A Q-switched Nd:YAG laser emitting pulses of 150 mJ energy, 6 ns duration, and 5 Hz repetition rate created the required plasma when focused on a 5-cm-long downward vertical laminar water jet generated from a 1-mm-diameter nozzle. Light emitted by the plasma is channeled by an optical fiber to an echelle spectrometer with an intensified CCD and a fast photodiode to generate a trigger signal. With delay times of 1 to 5 μs, output from 50 pulses are accumulated to produce one spectrum and three such spectra measured. To eliminate experimental fluctuations, the spectra of Pb and Cd were normalized to that of hydrogen (Hß). The LODs measured for Pb and Cd were 4 and 68 parts per million, respectively. Contact S. H. Tavassoli at [email protected].

About the Author

John Wallace | Senior Technical Editor (1998-2022)

John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.

Sponsored Recommendations

March 31, 2025
Enhance your remote sensing capabilities with Chroma's precision-engineered optical filters, designed for applications such as environmental monitoring, geospatial mapping, and...
March 31, 2025
Designed for compatibility with a wide range of systems, Chroma's UV filters are engineered to feature high transmission, superior out-of-band blocking, steep edge transitions...
March 31, 2025
Discover strategies to balance component performance and system design, reducing development time and costs while maximizing efficiency.
March 31, 2025
Explore the essential role of optical filters in enhancing Raman spectroscopy measurements including the various filter types and their applications in improving signal-to-noise...

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!