The development of organic thin-film transistors (OTFTs) with low power consumption and high gain will advance many flexible electronics. Here, by combining solution-processed monolayer organic crystal, ferroelectric HfZrOx gating and van der Waals fabrication, we realize flexible OTFTs that simultaneously deliver high transconductance and sub-60 mV/dec switching, under one-volt operating voltage. The overall optimization of transconductance, subthreshold swing and output resistance leads to transistor intrinsic gain and amplifier voltage gain over 5.3 × 104 and 1.1 × 104, respectively, which outperform existing technologies using organics, oxides and low-dimensional nanomaterials. We further demonstrate battery-powered, integrated wearable electrocardiogram (ECG) and pulse sensors that can amplify human physiological signal by 900 times with high fidelity. The sensors are capable of detecting weak ECG waves (undetectable even by clinical equipment) and diagnosing arrhythmia and atrial fibrillation. Our sub-thermionic OTFT is promising for battery/wireless powered yet performance demanding applications such as electronic skins and radio-frequency identification tags, among many others.

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Purpose -The purpose of this paper is to explore the long-term corrosion behavior of carbon steel in 3% NaCl solution and evaluate the effect of rust layer on the corrosion process. Design/methodology/approach -The corrosion behavior of rusted carbon steel in 3% NaCl solution was studied by means of infrared spectroscopy (IR) and electrochemical impedance spectroscopy (EIS). Findings -The results indicated that the corrosion of carbon steel was affected by chloride ion in initial immersion and then controlled by the rust layer. The rust layer consisted of a thin outer layer (g-FeOOH layer) and a thick inner layer (Fe 3 O 4 layer). The outer rust layer facilitated the cathodic process via reduction of g-FeOOH, while the inner rust layer provided a large cathode area and oxygen could be reduced on its surface. As a result, the corrosion rate of carbon steel was determined by the limiting diffusion rate of oxygen and stabilized at a high value. Originality/value -The corrosion model of rusted carbon steel in 3% NaCl solution was established. It is probable that the iron rust in all slightly acidic water with low alkalinity can promote the corrosion process via reduction of g-FeOOH. Anti-corrosion measures for iron in this type of solutions should be aimed to reduce the promoting effect of rust layer on the metal corrosion. The NaCl solution prepared from tap water is more suitable for the substitution of artificial water than that prepared from deionized water.

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Abstract-Life consumption monitoring is a prognostic method to assess the remaining life of a product in its actual life-cycle environment by continuously or periodically measuring the product's performance parameters and environmental conditions. This paper discusses a generic process to conduct a life consumption monitoring for electronic products. Two case studies on a circuit card assembly in an automobile under-hood environment are presented as application examples of the process. Temperature and vibration were identified as the dominant factors for the failure of the circuit card assembly. The environmental loads were monitored using a data recorder and the remaining life of the card assembly were estimated using physics-of-failure based stress and damage models. The predicted remaining life of the circuit card assembly correlated well with the measurement results.

The development of organic thin-film transistors (OTFTs) with low power consumption and high gain will advance many flexible electronics applications. Here, by combining solution-processed monolayer organic crystal, ferroelectric HfZrOx gating and van der Waals device fabrication, we realize flexible OTFTs that simultaneously deliver high transconductance and sub-60mV/dec switching, under one-volt operating voltage. The overall optimization of transconductance, subthreshold swing and output resistance leads to transistor intrinsic gain and amplifier voltage gain over 5.3×104 and 1.1×104, respectively, which outperform existing technologies using organics, oxides and low-dimensional nanomaterials. We further demonstrate battery-powered, integrated wearable electrocardiogram (ECG) and pulse sensors that can amplify human physiological signal by 900 times with high fidelity. The sensors are capable of detecting extremely weak ECG waves (undetectable even by clinical equipment) and diagnosing arrhythmia and atrial fibrillation. Our sub-thermionic OTFT is promising for battery/wireless powered yet performance demanding applications such as electronic skins, radio-frequency identification tags, among many others.