Scope

The IIT Chemical Sensor Research Group (SRG) is located in the BCPS Department of the Armour College of Engineering and Science at Illinois Institute of Technology. The IIT SRG performs basic and applied research in Analytical Chemistry, Environmental Chemistry, and Electrochemistry. The projects are focused on understanding and developing chemical sensors and sensor array instrumental devices with novel structures and new materials. General physical, analytical, and bioanalytical chemistry problems are researched and applications that span various industrial and medical needs, from instrument development to sensor manufacturing, including microfabrication and nanofabrication, are addressed. This interdisciplinary work is accomplished through close collaborations with allied disciplines including biology, physics, and electrical and mechanical engineering. Senior personnel in the group have more than 50 years cumulative experience in chemical sensors, sensor arrays, and their applications. Typical projects have ranged from a study of the gas phase electrochemical reactions of CO, H₂, and NO on Pt and Au electrocatalysts to the development of a sensor fabrication process as a statistical process control tool for sensor manufacturing. The SRG has a unique Sensor Technology User Center for evaluation of critical specifications for Center members and for the sensor user community as well.

The Sensor Research Group [SRG]

The Sensor Research Group was organized by Dr. Joseph R. Stetter, Professor of Chemistry. The SRG is formed of professors, engineers, scientists, and postdoctoral associates, as well as graduate and undergraduate students, visiting scholars, and academic or industrial collaborators. Dr. Stetter has extensive experience in the development and manufacture of sensors and has held both research and management positions in industry, national laboratories, and academia as well as experience in mentoring and teaching.

The SRG is staffed by Dr. Stetter, Dr. W. R. Penrose (Sr. Research Associate), Dr. Sheng Yao (Sr. Research Associate) and graduate students (Mr. Chao, Mr. Roh, Ms. Lin, Ms. McEntegart). Additional Teaching Assistants and undergraduate students are from chemistry, biology, and chemical engineering disciplines and are complemented by an ever-present number of visiting engineers and scientists. The group is truly interdisciplinary in their interests and capabilities. A list of current and past group members can be found below.

Ongoing and Recent Projects

The IIT Sensor Research Group, while studying the basic analytical characteristics of sensors, focuses on real world applications. These projects include the following.

Remote Sensing of Non-Accidental Releases from Tank Cars

A Specialized chemical sensors and cellular telecommunications technology can be used to detect and locate leakage of dangerous or expensive products from tank cars anywhere and report via internet. The sensor-telecom technology has applications in worker safety, inventory management, security, and anti-terrorism.

High-Performance Sensors for Carbon Monoxide and Hydrogen

Ultra low cost sensors with high selectivity and fast response times are being developed to accommodate the needs of the automotive industry, both today’s technology and future fuel cell-driven vehicles. Novel nanoparticulate-catalyst formulations, novel high temperature electrolytes, and simple, integral designs are combined to yield high performance within a rugged and very low-cost outcome.

(Low-cost CO, H₂, and H₂S CP sensor package.)

Microfabricated Array (“ChemArrayChip”)

An array of over 93,000 capacitive sensors automatically detects small particles and many types of chemical reactions taking place within nanometers of its surface. It can image pollen particles the size of bacterial spores and living cells according to electrical impedance, and may be useful for selectively detecting micro-organisms and spores in air and liquids. The ChemArrayChip is currently being investigated as a biowarfare agent detector, as well as for bioanalytical and biomedical applications.

Sensor Technology User Facility

The user facility is a growing and extensible work center that will ultimately be capable of testing sensors for almost any application, under wide ranges of environmental conditions. Its first application is to monitor the development of process control sensors for automotive fuel cells, involving unusual gas mixtures, wide swings in temperature and pressure, and fast response times. For commercial users, confidentiality can be assured.

Sensor Array (Electronic Nose) Methods

The so-called “electronic nose” can distinguish disease-causing organisms from harmless ones, and dangerous chemicals like explosives from nonhazardous chemicals. We are pursuing a test for tuberculosis based on sensor analysis of the breath or cultured samples. Beyond infections and diagnosis, other applications such as food freshness, product quality, and product history have been shown to be viable and are being investigated. The unique heterogeneous array features many types of sensors allowing the best of them to be selected for a given application.

Cultures of tuberculosis bacteria grown for headspace gas collection.

Selective Sensors for Ammonia, Hydrogen Sulfide, Nitrogen Oxides, and Other Gases

Low cost sensors use molecular approaches to measure these important gases in environmental and process applications, in both mild and harsh environments. The use of low cost molded conductive plastic designs insure simplicity and long lifetime in sensors.

SRG Laboratory Facilities

The research laboratories for Dr. Stetter’s Sensor Research Group has a modern laboratory space of more than 3,000 ft² containing several gas chromatographs (HP5890 w/FID&ECD, Varian 3700, Carlo-Erba), GAMRY CMS-100 potentiostat and Cypress Systems bipotentiostat for electrochemistry research, custom-designed potentiostats for routine sensor work, 18-Mohm water filtration system, ionization detectors, optical microscopy, spot welding equipment, permeation and dilution systems for gas mixture preparation, environmental chamber, muffle furnaces, computerized data acquisition systems (including several LabView stations), Omnitherm SGA 1500 thermogravimetry apparatus, a vacuum vapor deposition system, computerized instrument control and operation systems, custom software, heat press, sensor assembly and test equipment, automated gas mixing equipment, regulators, pH meters, impedance meter, voltage supplies, signal generator and measuring instruments, power supplies, machine shop, electronic assembly area, library, and specialized electronic equipment such as two electronic noses. Chemical sensor design, fabrication, test and evaluation are routine activities of the laboratory.

Dr. Stetter and the IITSRG collaborates closely with several Chicagoland organizations, including Rush University and Medical Center, Cook County Hospital, the State of Illinois Department of Health Infectious Diseases Laboratory, the National Center for Food Safety Technology, IIT Research Institute, University of Illinois at Chicago, UIC’s Microfabrication Applications Laboratory, The University of Chicago, and Argonne National Laboratory. The close proximity of these institutions provides ready access to additional expertise, equipment, libraries, and resources. Since the resources of these institutions are located near IIT and easily accessed, sponsors are provided with unique research and development services generally available at only the largest research and development laboratories. These research services are provided with the speed, flexibility, and cost-effectiveness of the small research university environment.

Staff

Dr. Joseph Stetter (Professor) is Group Leader and Center Director. Other current [2/2002] members of the Center are Dr. William Penrose (Sr. Research Associate), Dr. Sheng Yao (Sr. Research Associate), Mr. Nathan Schattke (visiting industrial engineer), and graduate students (Mr. Chao (chem.), Mr. Roh (chem.), Ms. McEntegart (biology), Mr. Patel (Computer Science), and Ms. Shan Lin (chem.) as well as undergraduates (Ms. Lonergan, (Molecular Biology and Biophysics)). The team hails from chemistry, biology, computer science, and chemical engineering disciplines, making the group truly interdisciplinary in their interests and capabilities. Former visiting scientists have included: Dr. Nicolae Barsan (physicist, Institute for Theoretical and Physical Chemistry, University of Tübingen, Germany, 1998), Dr. L. Kwong (visiting Fulbright Scholar, electrochemistry, Xavier University, Phillipines, 1999), Mr. Stefan Strathmann (graduate student, physical chemistry, University of Tübingen, Germany, 1998), and Ms. Ulrike Göpel (medical student, University of Cologne, Germany, 2000). The staff is a growing and vibrant group of scientists and professionals.