Nanostructured Porous Silicon and Luminescent Polysiloles as Chemical Sensors for Carcinogenic Chromium(VI) and Arsenic(V)EPA Grant Number: R829619
Title: Nanostructured Porous Silicon and Luminescent Polysiloles as Chemical Sensors for Carcinogenic Chromium(VI) and Arsenic(V)
Investigators: Trogler, William C. , Sailor, Michael J.
Institution: University of California - San Diego
EPA Project Officer: Savage, Nora
Project Period: January 1, 2002 through December 31, 2004
Project Amount: $400,000
RFA: Exploratory Research: Nanotechnology (2001) RFA Text | Recipients Lists
Research Category: Nanotechnology , Safer Chemicals
Description:The chief goal is to develop new selective solid state sensors for carcinogenic and toxic chromium(VI) and arsenic(V) in water based on redox quenching of the luminescence from nanostructured porous silicon and polysiloles.
Approach:Nanostructured porous silicon, as well as polysilole nanowire coatings, will be chemically modified to enhance binding of the chromate and arsenate anions. Chemical modification to vary the redox potential of the polysilole excited state will also be used as a way to impart chemical selectivity. Both sensor approaches will be combined by encapsulating the polysilole in a nanotextured microcavity between two Bragg stacks constructed from porous silicon. Such optical devices have been shown to provide significant detection sensitivity enhancements. The nanoporous material will readily admit small inorganic analytes, such as chromate and arsenate, and exclude biomolecules that might confound the measurements. Sensors based on silicon wafer and polymer technologies are also readily adaptable to fabrication. The fluorescence quenching detection modality is also manufacturable. The essential electronics requires a blue or UV LED as the excitation source and an inexpensive photodiode detector.
Expected Results:Potential applications of such real time solid state sensors include remote sensing and industrial process control. The focus on chromium(VI) and arsenic(V) detection is dictated by the redox quenching mechanism that is being used, as well as by the importance of chromium(VI) and arsenic(V) as regulated chemicals under the Safe Drinking Water Act. The results address the needs identified in the solicitation as nanotechnology is applied to the development of solid state sensors that can be used to monitor pollutants in water that are currently of great concern to the EPA's regulatory mission.
Publications and Presentations:Publications have been submitted on this project: View all 25 publications for this project
Journal Articles:Journal Articles have been submitted on this project: View all 6 journal articles for this project
Supplemental Keywords:water, drinking water, groundwater, carcinogen, toxics, heavy metals, effluent, discharge, innovative technology, monitoring, analytical, measurement methods, remote sensing, industry., RFA, Scientific Discipline, Toxics, Water, Ecosystem Protection/Environmental Exposure & Risk, POLLUTANTS/TOXICS, Sustainable Industry/Business, National Recommended Water Quality, Sustainable Environment, Physics, Environmental Chemistry, Chemistry, Arsenic, Technology for Sustainable Environment, Analytical Chemistry, Monitoring/Modeling, Biochemistry, New/Innovative technologies, Chemistry and Materials Science, Water Pollutants, Engineering, Environmental Engineering, 33/50, biosensing, nanosensors, environmental monitoring, chemical sensors, chromium & chromium compounds, nanotechnology, environmental sustainability, polysiloles, environmentally applicable nanoparticles, chemical sensor, nanostructured porous silicon, carcinogens, sustainability, water quality, innovative technologies
Progress and Final Reports:2002 Progress Report
2003 Progress Report