Electrospining Machine: Prof Guozhen Shen et al, Beijing Institute of Technology, Nano Research: multi-attribute wearable pressure sensors for high constant sensitivity

Background

Flexible pressure sensors capable of monitoring a wide range of physiological signals and body movements have attracted significant attention in wearable electronic devices. Among them, high constant sensitivity over a wide pressure range combined with breathability, biocompatibility, and biodegradability is the key to fabricate reliable pressure sensors in practical sensing applications.

Recently, inspired by the multilayered structure of skin epidermis, a team of Prof Guozhen Shen from Beijing Institute of Technology and Prof Yang Li from Jinan University proposed and demonstrated a multi-attribute wearable piezoresistive pressure sensor consisting of a multilayered gradient-conducting poly (ε-caprolactone) Nanofiber Membrane composite. The related research is published under the title ‘Multi-attribute wearable pressure sensor based on multilayered modulation with high constant sensitivity over a wide range ‘The research was published in the journal Nano Research.

The main points of this paper

1. This study proposes and demonstrates a multi-attribute wearable piezoresistive pressure sensor consisting of a multilayer gradient conductive poly (ε-caprolactone) Nanofiber Membrane composite.

2. Under the effect of externally applied pressure, the layer-by-layer current pathway inside the multilayer membrane composite is activated, which has the highest constant sensitivity of 33.955 kPa-1 sensing performance in the pressure range of 0-80 kPa.

3. The pressure sensor features fast response relaxation time, low detection limit, and good stability, which can be successfully used for human physiological signal measurement.

4. Finally, an integrated sensor array system capable of locating the position of an object was constructed and applied to simulated sitting posture monitoring.

Structural design of pressure sensors

1. Firstly, PCL Electrospun Nanofbers with high porosity and permeability were prepared by electrostatic spinning technique;

2. Then, the conductive Ag NWs/PCL NFs were prepared by spraying Ag nanowires on the PCL Electrospun Nanofbers; the oxygen plasma treatment promoted the hydrophilicity enhancement of polyaniline, so that the polyaniline could be easily deposited on the NFs of the PCL, and the conductive PANI-PCL NFs composites with core-shell structure were formed.

(a) Structural diagram of a multi-attribute pressure sensor with high constant sensitivity over a wide range. (b) Schematic diagram of wearable pressure sensor for human physiological signal monitoring. (c) Preparation process of piezoresistive layer. (d) Preparation process of electrode

Originallink:https://doi.org/10.1007/s12274-022-5371-6