Highly Strain‐Stable Intrinsically Stretchable Olfactory Sensors for Imperceptible Health Monitoring

Abstract

Intrinsically stretchable gas sensors possess outstanding advantages in seamless conformability and high‐comfort wearability for real‐time detection toward skin/respiration gases, making them promising candidates for health monitoring and non‐invasive disease diagnosis and therapy. However, the strain‐induced deformation of the sensitive semiconductor layers possibly causes the sensing signal drift, resulting in failure in achievement of the reliable gas detection. Herein, a surprising result that the stretchable organic polymers present a universal strain‐insensitive gas sensing property is shown. All the stretchable polymers with different degrees of crystallinity, including indacenodithiophene‐benzothiadiazole (PIDTBT), diketo‐pyrrolo‐pyrrole bithiophene thienothiophene (DPPT‐TT) and poly[4‐(4,4‐dihexadecyl‐4H‐cyclopenta[1,2‐b:5,4‐b′]dithiophen‐2‐yl)‐alt‐[1,2,5]thiad‐iazolo [3,4‐c] pyridine] (PCDTPT), show almost unchanged gas response signals in the different stretching states. This outstanding advantage enables the intrinsically stretchable devices to imperceptibly adhere on human skin and well conform to the versatile deformations such as bending, twisting, and stretching, with the highly strain‐stable gas sensing property. The intrinsically stretchable PIDTBT sensor also demonstrates the excellent selectivity toward the skin‐emitted trimethylamine (TMA) gas, with a theoretical limit of detection as low as 0.3 ppb. The work provides new insights into the preparation of the reliable skin‐like gas sensors and highlights the potential applications in the real‐time detection of skin gas and respiration gas for non‐invasive medical treatment and disease diagnosis.

Highly Sensitive, Low-Energy-Consumption Biomimetic Olfactory Synaptic Transistors Based on the Aggregation of the Semiconductor Films

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Intrinsically stretchable organic field-effect transistors: progress and challenges

“…Tang et al addressed this need by preparing intrinsically stretchable FET-type gas sensors, employing IDTBT as the semiconductor layer, PDMS as the insulating layer, and PEDOT:PSS/SWCNT as the electrodes. 53 They found that the ultra-large molecular spacing of polymer semiconductors allowed gas molecules to diffuse, regardless of whether the semiconductor was stretched or not. Therefore, the stretchable polymer semiconductor had strain-insensitive gas-sensing properties.…”

A Dual-Mode Flexible Sensor Based on the Combination of Triboelectric and Piezoresistive Sensing to Simultaneously Monitor Non-Contact/Contact Pressure

“…The rapid development of sensing technology provides important technical support for human beings to effectively monitor the surrounding physical space, greatly enhancing their ability to cope with various emergencies. Various types of sensors have shown great potential for development in the fields of industrial production, intelligent medical care, , human–computer interaction systems, − as well as physiological signal perception − and motion pattern recognition. − Capacitive and piezoresistive sensors are the most commonly used in flexible pressure sensors. Both types of sensors have their unique advantages.…”