Quantitative Study of the Resolving Power of Arrays of Carbon Black−Polymer Composites in Various Vapor-Sensing Tasks

Abstract

A statistical metric, based on the magnitude and standard deviations along linear projections of clustered array response data, was utilized to facilitate an evaluation of the performance of detector arrays in various vapor classification tasks. This approach allowed quantification of the ability of a 14-element array of carbon black-insulating polymer composite chemiresistors to distinguish between members of a set of 19 solvent vapors, some of which vary widely in chemical properties (e.g., methanol and benzene) and others of which are very similar (e.g., n-pentane and n-heptane). The data also facilitated evaluation of questions such as the optimal number of detectors required for a specific task, whether improved performance is obtained by increasing the number of detectors in a detector array, and how to assess statistically the diversity of a collection of detectors in order to understand more fully which properties are underrepresented in a particular set of array elements. In addition, the resolving power of arrays of carbon black-polymer composites was compared to the resolving power of specific collections of bulk conducting organic polymer or tin oxide detector arrays in a common set of vapor classification tasks.

Combinatorial Approaches to the Synthesis of Vapor Detector Arrays for Use in an Electronic Nose

“…14 The detector films were spray coated onto the surface of a glass slide onto * Authors to whom correspondence should be addressed. which Au lines had been deposited by thermal evaporation.…”

In-Situ Chemiresistor Sensor Package for Real-Time Detection of Volatile Organic Compounds in Soil and Groundwater

“…First, the architecture of the microsensor integrates an array of chemiresistors with a temperature sensor and heating elements (Figure 2) [6]. The array of differing sensors can be used to identify different VOCs by comparing the resulting chemical signatures with calibration (or training) sets and pattern-recognition methods [7][8][9][10][11][12]. The chemiresistor array has been shown to detect a variety of VOCs including aromatic hydrocarbons (e.g., benzene), chlorinated solvents (e.g., trichloroethylene (TCE), carbon tetrachloride), aliphatic hydrocarbons (e.g., hexane, iso-octane), alcohols, and ketones (e.g., acetone) [12][13].…”

Assessing the ability to predict human percepts of odor quality from the detector responses of a conducting polymer composite-based electronic nose

“…A total of 20 insulating polymers were used to form the carbon black/ polymer composite detectors in the electronic nose (Table 2). Detectors were fabricated as described previously [12].…”

“…The electrical output signals from an array of such detectors are then transferred to a central processing unit for odorant analysis and classi®cation. This implementation of an electronic nose was chosen for study because it is readily investigated experimentally [11], allows inclusion of a chemically diverse set of detectors [12], has been shown to parallel mean human olfactory detection threshold behavior for several classes of organic vapors [10], and has been shown in selected test cases to parallel human and monkey olfaction in the positive correlation between its discrimination ability and the chemical dissimilarity between members of a pair of odorants [13].…”