Highly sensitive and transparent flexible temperature sensor based on nematic liquid crystals

ABSTRACT

In this paper, a highly sensitive and transparent flexible temperature sensor fabricated from the polyethylene terephthalate flexible substrate and the nematic liquid crystal (1M0921900-000) is proposed, which simultaneously has low power consumption. Using the relaxation time (τ = RC) as an intrinsic variable to characterise temperature, a better linear fitting with temperature can be obtained at low voltage, high precision and more stable temperature monitoring can be achieved. The maximum sensitivity is −4.05%/°C at 0.1 V and 200 Hz. The transmittance of the sensor can reach 62.36–81.13% in the visible light range. Compared with the rigid liquid crystal temperature sensor, the rise time and the decay time of the sensor are reduced by 97.104% and 90.313%, respectively. In addition, it also has good stability, recovery, and durability, which shows potential applicability to electronic skin, prostheses, robots, and biomedical by accurately monitoring the change of external temperature.

Graphical abstract

KEYWORDS:

• Liquid crystal temperature sensor
• flexible
• relaxation time
• thermal effect
• electronic skin

Disclosure statement

No potential conflict of interest was reported by the authors.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This research is supported by the National Natural Science Foundation of China (NSFC) [11374087, 11504080]; the Natural Science Foundation of Hebei Province of China [A2019202235, A2022202004]; the Key Subject Construction Project of Hebei Province University; Science and Technology Project of Guannan County [GN202101].