Carbon nanocoils (CNCs) are employed to fabricate fast, high-resolution, and reversible humidity sensor based on a flexible liquid crystal polymer (LCP) substrate. The humidity sensor displays fast-response (1.9 s) and recovery time (1.5 s), a broad relative humidity (RH) detection range (4−95%), linearity, repeatability, and stability. The rapid response and recovery are considered to benefit from the hydrophobic effect of the LCP substrate and high purity of the CNCs, which give rise to weak physical adsorption. Meanwhile, the high sensitivity results from both the unique helical structure of CNCs and the microporous structure of the LCP substrate. The distinctive structure-related properties enable the sensor to reliably perceive an extremely small RH variation of 0.8%, which is too small to be detected by most humidity sensors reported previously. These features allow the sensor to monitor a variety of important human activities, such as respiration, speaking, blowing, and noncontact fingertip sensation, accurately. Furthermore, different human physical conditions can be distinguished by recognizing the respiration response patterns. In addition, the long-term operation and mechanical bending do not adversely affect the sensing performance.

A series of new organic semiconductors for organic thin‐film transistors (OTFTs) using dithieno[3,2‐b:2′,3′‐d]thiophene as the core are synthesized. Their electronic and optical properties are investigated using scanning electron microscopy (SEM), X‐ray diffraction (XRD), UV‐vis and photoluminescence spectroscopies, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). The compounds exhibit an excellent field‐effect performance with a high mobility of 0.42 cm2 V–1 s–1 and an on/off ratio of 5 × 106. XRD patterns reveal these films, grown by vacuum deposition, to be highly crystalline, and SEM reveals well‐interconnected, microcrystalline domains in these films at room temperature. TGA and DSC demonstrate that the phenyl‐substituted compounds possess excellent thermal stability. Furthermore, weekly shelf‐life tests (under ambient conditions) of the OTFTs based on the phenyl‐substituted compounds show that the mobility for the bis(diphenyl)‐substituted thiophene was almost unchanged for more than two months, indicating a high environmental stability.

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