Multi‐Parametric Sensing Platforms Based on Nanoparticles

Abstract

(2) Humanoid robotics: detection and monitoring of static and dynamic changes in pressure, vibration and temperature, were reported for tactile sensing in robotics. [8] (3) Structural health monitoring: data from a range of sensors, including inclinometers, accelerometers, temperature and strain sensors were produced and associated with health monitoring features. [9] (4) Precision agriculture: a multi-parametric sensing platform that consist of real-time measurements of pH, electrical conductivity and temperature was established. [10] In general, distinct attempts have been conducted using both solid state [10] and flexible and/or stretchable sensors for fabrication and utilization of multi-parametric sensing platforms. [4,11] Nanomaterial-based sensors for multi-parametric sensing provide adjustable building blocks due to a number of synthesis and fabrication routes; thus, size, shape and functionalization groups can be predetermined and designed to fit specific stimuli. [12] Combining the power of nanomaterials (e.g., Si nanowires [13,14] and nanocomposites [15] ) with field effect transistor (FET) platforms provides the ability to extract several device features (e.g., for threshold voltage, charge carrier mobility) from a single measurement, each of which could be linked to different stimuli. The main drawback of this approach is usually the high voltages required, especially for organic FETs. [16] Electrically resistive technology, as opposed to FET fabrication processes, usually provide a low voltage operating platform that usually require fewer fabrication steps. Electrically resistive nanomaterial-based sensors for a multi-parametric sensing platform have also been reported with sensing components, such as nanowires, [17] carbon nanotubes, [18][19][20][21] organic films, [22,23] nanoparticles [24,25] and nanocomposite inks. [18] Figure 1 depicts the main approaches used for the realization of the multi-parametric sensing platform concept. One approach is based on the diversification of sensors placed in a single platform, where each sensor is sensitive to a specific stimulus. Such a platform usually has a relatively large number of sensing pixels, since each pixel is dedicated to a defined task, i.e., sensing a specific stimulus. Figure 1a gives an example of different sensors integrated on a 50 µm thick polyimide (PI) wafer: (i) metal oxide-based chemiresistive films that rely Multi-parametric sensing platforms offer the possibility to measure simultaneously several stimuli, and potentially to differentiate between the different signals. They have advantages in fields that include wearable systems, humanoid robotics, structural health monitoring and precision agriculture, since a complex stimuli from the environment is usually an integrated component in these examples. In the current progress report, we present and discuss new avenues in nanoparticle-based multi-parametric sensing platforms for the detection, classification and separation of common stimuli, e.g., temperature, humidity, strain/pressure ...

Electrostatically Actuated Membranes of Cross-Linked Gold Nanoparticles: Novel Concepts for Electromechanical Gas Sensors

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Time‐Resolved and Self‐Adjusting Hybrid Functional Fabric Sensor for Decoupling Multiple Stimuli from Bending

“…Multi‐parametric sensing fabrics that decouple different stimuli in a complex mixture or environment can be achieved usually by diversification of sensors placed on a single platform, where each sensor is sensitive to a certain stimulus, or a couple of stimuli, with signal variance in multiple dimensions . However, this approach could suffer from several obstacles, which include the need for numerous steps to fabricate such devices, cross‐talk between micrometer‐scale separated sensing elements,3,12b and difficulties in reducing the effect of confounding factors . Other approaches for decoupling the various stimuli include one or combination of the following: choosing an appropriate substrate; altering the functional groups of the sensing material or the fabrication parameters (e.g., by employing a layer‐by‐layer deposition technique) or controlling the layer's morphology (e.g., perforated vs continuous morphology); controlling the protective interface between the sensing layer and targeted environment; and using a post‐measurement algorithm 13a.…”

“…However, this approach could suffer from several obstacles, which include the need for numerous steps to fabricate such devices, cross‐talk between micrometer‐scale separated sensing elements,3,12b and difficulties in reducing the effect of confounding factors . Other approaches for decoupling the various stimuli include one or combination of the following: choosing an appropriate substrate; altering the functional groups of the sensing material or the fabrication parameters (e.g., by employing a layer‐by‐layer deposition technique) or controlling the layer's morphology (e.g., perforated vs continuous morphology); controlling the protective interface between the sensing layer and targeted environment; and using a post‐measurement algorithm 13a. Although much progress has been made with these approaches, considerable cost and sophisticated design—with adequate chemical diversity to differentiate stimuli—are often required in fabricating most planar sensor arrays.…”