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Pain‐perceptual Nociceptors (PPNs) in the biological sensory system are critical for the human body to perceive noxious stimuli from the outside world and start appropriate motor responses to minimize potential physical damage. Realization artificial nociceptors with unique synaptic and pain‐perceptual functions of the human nervous system is a key step to develop the next‐generation artificial intelligence systems. Here, an artificial pain‐perceptual device based on an ionic liquid‐polymer solid‐state electrolyte‐gated poly(3‐hexylthiophene) (P3HT) transistor is reported. With the drift motion of mobile ions in the electrolyte layer and the formation of an electric double layer (EDL) at electrolyte/semiconductor interface under an applied electric field, the channel conductance can be tuned progressively to exhibit synaptic weight modulation function. On top of the artificial synaptic functions, the P3HT/electrolyte‐based transistor successfully emulates the pain‐perception process in a biological nociceptor, with all unique features of threshold, no adaptation, sensitization/desensitization, and relaxation. Moreover, the pain conditioning process (i.e., hyperalgesic response, and pain extinction effect) through associative learning is demonstrated using the artificial synaptic transistor, indicating its potential application in bio‐inspired neural systems. [ABSTRACT FROM AUTHOR]

Many advanced materials have been developed for organic field‐effect transistors (OFETs) or thin‐film transistors (TFTs) based on organic and organic hybrid materials. However, although many new OFETs exhibit superior characteristic parameters (such as high mobility), most of them show nonideal performances that have strongly limited progress in the design of molecules, the understanding of transport mechanisms, and the circuit applications of OFETs. In this review, the device physics of ideal and nonideal OFETs is discussed first to understand the factors that limit effective mobility in semiconducting channels, distort the potential distribution, or reduce the drift electric field. Then, recent advances in optimizing the material combinations, device structures, and fabrications of OFETs toward ideal transistors are discussed. Based on the good control of materials and interfaces, some new and novel concepts to utilize the nonideal properties of OFETs to build low‐power circuits and integrated sensors are also discussed. [ABSTRACT FROM AUTHOR]

The rapid sintering of printable metal nanoparticle inks is vital for the industrial mass production of electronic devices. In this paper, we report a rapid laser annealing method for printed Ag nanoparticle-based inks. We also fabricate Ag circuits and organic thin-film transistors (OTFTs) on flexible plastic substrates through spontaneous patterning under deep ultraviolet (DUV) exposure. Compared to the conventional thermal annealing, laser annealing significantly reduces the processing time from 3600 to 10 s while preventing damage caused by excessive heat. The OTFT with laser-annealed Ag source/drain electrodes achieved good performance with saturated mobility of 1.68 cm $^{{2}}\cdot \text{V}^{-{1}}\cdot \text{s}^{-{1}}$ , high-reliability factor of 86.75%, and large saturated drain current resulting from the small channel resistance. This rapid laser annealing method is feasible for printing flexible electronics using metal nanoparticle-based inks in industrial mass production. [ABSTRACT FROM AUTHOR]

Abstract: Precise patterning of solution‐processed oxide semiconductors is critical for cost‐effective, large‐scale, and high throughput fabrication of circuits and display application. In this paper, demonstration and comparison are made using the additive and subtractive patterning strategies to precisely fabricate wafer‐scale thin film transistor arrays (1600 devices), which are based on high‐quality solution‐processed indium zinc oxide (IZO) and indium gallium zinc oxide (IGZO). The IZO and IGZO TFTs exhibit field‐effect mobility up to 8.0 and 5.2 cm2 V−1 s−1 when using the additive method, whereas the highest mobility of 24.2 and 13.7 cm2 V−1 s−1 for IZO and IGZO TFTs is achieved when using the subtractive method. The X‐ray photoelectronic spectroscopy studies and quantitative 2D device simulations together reveal that good device performance is attributed to moderate shallow donor‐like states (providing electrons) from oxygen vacancy and few accepter‐like states (trapping electrons) resulted from the dense structural framework of MO bonds. After examining the uniformity and reliability of the devices, the solution‐patterned inverters are demonstrated using negative‐channel metal oxide semiconductors, which show full swing output transfer characteristics and thus provide a promising method for solution‐based fabrications of circuits. [ABSTRACT FROM AUTHOR]

Abstract: A diode-pumped passively Q-switched Nd:YAG/SrWO4/KTP yellow laser is presented for the first time. As high as 1.02W average output power was obtained at a pump power of 14.0W with a pulse repetition frequency of 21.9kHz and the corresponding diode-to-yellow conversion efficiency was 7.29%. The highest pulse energy of 56.2μJ was obtained at a pump power of 7.2W. [Copyright &y& Elsevier]

2,2′-Position aryl-substituted tetracarboxylic dianhydrides including 2,2′-bis(biphenyl)-4,4′,5,5′-biphenyl tetracarboxylic dianhydride and 2,2′-bis[4-(naphthalen-1-yl)phenyl)]-4,4′,5,5′-biphenyl tetracarboxylic dianhydride were synthesized. A new series of aromatic polyimides (PIs) were synthesized via a two-step procedure from 3,3′,4,4′-biphenyl tetracarboxylic dianhydride and the newly synthesized tetracarboxylic dianhydrides monomers reacting with 2,2′-bis[4′-(3″,4″,5″-trifluorophenyl)phenyl]-4,4′-biphenyl diamine. The resulting polymers exhibited excellent organosolubility and thermal properties associated with Tg at 264 °C and high initial thermal decomposition temperatures ( T5%) exceeding 500 °C in argon. Moreover, the fabricated sandwich structured memory devices of Al/PI-a/ITO was determined to present a flash-type memory behaviour, while Al/PI-b/ITO and Al/PI-c/ITO exhibited write-once read-many-times memory capability with different threshold voltages. In addition, Al/polymer/ITO devices showed high stability under a constant stress or continuous read pulse voltage of − 1.0 V. Copyright © 2011 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The rate equations for the quasi-three-level actively Q-switched lasers are obtained by considering the reabsorption of the lower laser level and the spatial distributions of the intracavity photon density and the population inversion density. These rate equations are normalized by introducing three new parameters. By solving the normalized rate equation numerically, a group of general curves is generated. These curves can give a good understanding of the dependences of the laser pulse characteristics on the new parameters. The curves and the related formulae can also be used to estimate the laser pulse characteristics of any quasi-three-level actively Q-switched laser. A sample calculation for a 946-nm actively Q-switched Nd:YAG ceramic laser is presented to demonstrate the use of the related formulae. [ABSTRACT FROM AUTHOR]

Ionic hydrogels with intrinsic conductivity and stretchability show great potential in flexible electronics. However, it remains a great challenge to achieve hydrogels with mechanical stretchability, ionic conductivity, optical transparency, and a self-healing ability at the same time. In this paper, we developed a hydroxyethylidene diphosphonic acid (HEDP) assisted poly(vinyl alcohol) (PVA) composite hydrogel to achieve high-performance stretch-sensitive sensor. Through a facile freeze–thaw strategy, the hydrogel could achieve large stretchability (up to 950% strain), good conductivity (10.88 S/m), excellent linear sensitivity (GF = 2.72, within 100% strain), high transparency, and significant self-healing ability. The PVA-HEDP hydrogel-based strain sensor is capable of monitoring various human movements from small scale (e.g., laryngeal vibration while speaking) to large scale (e.g., knee joint movement). Moreover, the multisite sensor array is capable of detecting the subtle differences between the pulse wave features from Cun, Guan and Chi positions, mimicking the three-finger palpation in Traditional Chinese Medicine. This work demonstrates that the composite hydrogel-based flexible sensor provides a promising solution for multifunctional human activities and health monitoring. [ABSTRACT FROM AUTHOR]

Nonideal Transistors: Understanding, Optimizing, and Utilizing Nonideal Transistors Based on Organic or Organic Hybrid Semiconductors (Adv. Funct. Keywords: device physics; field-effect transistor; organic semiconductor; reliability; thin-film transistor EN device physics field-effect transistor organic semiconductor reliability thin-film transistor 1 1 1 05/18/20 20200515 NES 200515 In article number 1903889, Chuan Liu and co-workers review the origins and critical factors that lead to organic field-effect transistors (OFETs) with deviations from the ideal device models in terms of device physics. Device physics, field-effect transistor, organic semiconductor, reliability, thin-film transistor. [Extracted from the article]

In this paper, a high‐performance pressure sensor that imitates the sensing functions of human skin is proposed. A rough poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) film transferred from abrasive paper acts as the sensing layer, while silver nanowires deposited on the bottom Ecoflex film with a 3D microstructure serve as the electrodes. Because of the bionic hierarchical structure, the resulting sensor exhibits a high pressure sensitivity of 6.13 kPa−1, low limit of detection (20 Pa), low operating voltage (0.1 V), and broad sensing range (up to 90 kPa). Furthermore, as the sensor is ultrathin, ultraflexible, and stretchable, it can easily conform to the uneven surface of human skin to allow monitoring of physical signals from the human body or detect the tactile stimulation of objects. In addition, a sensor array consisting of 4 × 4 pixels is assembled to realize the precise mapping of spatial pressure distribution. By virtue of its superior performance and low‐cost fabrication, the proposed pressure sensor may potentially be applied to next‐generation wearable devices such as e‐skin, soft robotics, and human–machine interaction systems. [ABSTRACT FROM AUTHOR]

A continuous roll-to-roll microcontact printing (MCP) platform promises large-area nanoscale patterning with significantly improved throughput and a great variety of applications, e.g. precision patterning of metals, bio-molecules, colloidal nanocrystals, etc. Compared with nanoimprint lithography, MCP does not require a thermal imprinting step (which limits the speed and material choices), but instead, extreme precision with multi-axis positioning and misalignment correction capabilities for large area adaptation. In this work, we exploit a flexure-based mechanism that enables continuous MCP with 500 nm precision and 0.05 N force control. The fully automated roll-to-roll platform is coupled with a new backfilling MCP chemistry optimized for high-speed patterning of gold and silver. Gratings of 300, 400, 600 nm line-width at various locations on a 4-inch plastic substrate are fabricated at a speed of 60 cm/min. Our work represents the first example of roll-to-roll MCP with high reproducibility, wafer scale production capability at nanometer resolution. The precision roll-to-roll platform can be readily applied to other material systems. [ABSTRACT FROM AUTHOR]

Abstract: A new ternary samarium complex Sm(β-NBM)3·(PD) has been synthesized by the reaction of SmCl3·6H2O with β-naphthoylbenzoylmethane (β-HNBM) and 1,10-phenanthroline-5,6-dione (PD) in stoichiometry. The new samarium complex obtained was characterized by elemental analysis, 1H NMR, and FT-IR spectroscopy. The absorption and emission of this complex were systematically investigated. Photoluminescence studies indicated that the energy absorbed by the organic ligands was efficiently transferred to the central Sm3+ ions and the complex showed intensely and characteristically orange emission due to the 4 G 5/2→6 H j transitions of the central Sm3+ ions. The energy levels (HOMO and LUMO) of the ligands and the complex were further confirmed by computer simulation and cyclic voltammetry, respectively. All the results suggested that the synthesized Sm(β-NBM)3·(PD) would have the potential application for organic light-emitting diodes. [Copyright &y& Elsevier]