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Abstract There are advantages to polymer/nanoparticle composite‐based volatile organic compounds (VOCs) sensors, such as high chemical and physical stability, operability under extreme conditions, flexible use in manufacturing, and low cost. Nevertheless, their lower limit of detection due to thickness‐dependent diffusion has constrained their application. Inspired by the metaxylem in vascular plants and its vertical conduits and horizontal pits that enable efficient transpiration, a polymer/nanoparticle composite‐based sensor is fabricated with a controllable, spontaneously formed, hollow core for inline VOCs transportation, and porous microstructure for radial direction diffusion. The hollow core is surrounded by an inner porous layer (thermoplastic polyurethane (TPU)), a middle sensing layer (TPU/graphene nanoplatelets/multiwalled carbon nanotubes), and an outer mechanically durable layer (TPU). This multilayered structure shows a 600% higher response rate compared to a single‐layered composite fiber sensor, with a low limit of detection (e.g., ≈15 ppm for xylene) and high selectivity based on the Flory–Huggins interaction parameter. This flexible and stretchable sensor also demonstrates a dual parameter sensing capability from VOC concentrations and uniaxial strain deformation. Via a one‐step fiber spinning procedure, this self‐induced hollow fiber offers a unique method of microstructural design, which enables the detection of low‐concentration VOCs by polymer/nanoparticle‐based sensors.
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Copper Phthalocyanine for Designing a Highly Selective and Disposable Electrochemical Volatile Organic Compound (VOC) Sensor
Abstract Formic acid (FA) is one of the very important organic acids that has been widely used in various industries. The highly corrosive FA can have severe adverse effects on the surrounding environment. Here, we developed an electrochemical sensor that utilizes the material properties of multi‐walled carbon nanotubes (MWCNTs), and copper phthalocyanine (CuPc) for the real‐time detection of FA gas. The response of FA has been compared with the responses of 9 common volatile organic compounds (VOCs). The chronoamperometry (CA) results revealed a high selectivity towards FA by showing an increase in the sensor current by about 25 %, in contrast to the decrease of the current in response to the other VOCs. The sensitivity of the CuPc device to FA was calculated to be 38.85 mAM−1. Material characterization (SEM, EDX, FTIR, Raman, and UV‐vis) also strongly suggests a protonation mechanism caused by the carboxylic acid group, which enhances the electrical conductivity.
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- PAR ID:
- 10641787
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Analysis & Sensing
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2629-2742
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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