In this work, we report single-walled carbon nanotubes (SWCNTs) synaptic transistors with high photoresponsivity at 940 nm, achieved by functionalizing the channel with the narrow-bandgap photosensitive molecule-IEICO-4F. Under 940-nm pulsed illumination, the devices exhibit clear synaptic behaviors, including excitatory postsynaptic current (EPSC), paired-pulse facilitation, and a tunable transition from short-term to long-term plasticity. The optoelectronic synaptic transistors operate at VDS of -10 & micro;V with an ultra-low energy consumption of 54.8 aJ per synaptic event and maintain stable EPSCs after 30 days of ambient storage, demonstrating outstanding power efficiency and long-term reliability. Leveraging our device's performance, we demonstrate a covert, event-driven 940-nm Near-infrared (NIR) optical tripwire for monitoring indoor trajectories under near-dark conditions. Furthermore, we exploit the device's conductance states to emulate network weights, achieving 96.63% accuracy on MNIST with a spiking neural network and demonstrating its utility in covert imaging by attaining 91.37% aircraft recognition accuracy with a convolutional neural network under 940-nm NIR illumination.

The advent of flexible single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) has transformed electronics, providing significant benefits like low operating voltage, reduced power consumption, cost-effectiveness, and improved signal amplification. This study focuses on leveraging these attributes to develop a novel flexible high-sensitivity and energy-efficient chloride ion sensors based on printed flexible SWCNT-TFTs utilizing polymers-sorted semiconducting SWCNTs (sc-SWCNTs) as the active layers and ion liquids-poly(4-vinylphenol as dielectric layers along with the evaporated deposition of aluminum electrodes and printed silver electrodes as the gate and source-drain electrodes, respectively. The sensors exhibit several operational advantages, including low voltage requirements (≤1 V), rapid response speed (5.32 s), significant signal amplification (Up to 702.6%), low power consumption (0.31 μJ at 1 mmol chloride ion), good repeatability, high sensitivity for both low and high concentrations of chloride ion (up to 100 mmol/L) and excellent mechanical flexibility (No obvious changes after bending for 10,000 times with a 5 mm radius). The detection mechanism of chloride ions was analyzed using X-ray Photoelectron Spectroscopy (XPS). It was found that chloride ions react with silver nanoparticles (AgNPs) to form silver chloride (AgCl) on printed electrodes, impeding carrier transport and reducing the currents in SWCNT TFTs. Importantly, our sensors' compatibility with smart devices allows for real-time monitoring of chloride ion levels in human sweat, offering significant potential for daily health monitoring.

Radiation-tolerance and repairable flexible transistors and integrated circuits (ICs) with low power consumption have become hot topics due to their wide applications in outer space, nuclear power plants, and X-ray imaging. Here, we designed and developed novel flexible semiconducting single-walled carbon nanotube (sc-SWCNT) thin-film transistors (TFTs) and ICs. Sc-SWCNT solid-electrolyte-gate dielectric (SEGD) TFTs showcase symmetric ambipolar characteristics with flat-band voltages (VFB) of ∼0 V, high ION/IOFF ratios (>105), and the recorded irradiation resistance (up to 22 Mrad). Moreover, flexible sc-SWCNT ICs, including CMOS-like inverters and NAND and NOR logic gates, have excellent operating characteristics with low power consumption (≤8.4 pW) and excellent irradiation resistance. Significantly, sc-SWCNT SEGD TFTs and ICs after radiation with a total irradiation dose (TID) ≥ 11 Mrad can be repaired after thermal heating at 100 °C. These outstanding characteristics are attributed to the designed device structures and key core materials including SEGD and sc-SWCNT.

The threshold voltage (Vth ) adjustment of complementary metal-oxide-semiconductor (CMOS) thin film transistors (TFTs) is one of the research hotspots due to its key role in energy consumption control of CMOS circuits. Here, ultralow-power flexible CMOS circuits based on well-matched enhancement-mode (E-mode) CMOS single-walled carbon nanotube (SWCNT) TFTs are successfully achieved through tuning the work function of gate electrodes, electron doping, and printing techniques. E-mode P-type CMOS SWCNT TFTs with the full-solution procedure are first obtained through decreasing the work function of Ag gate electrodes directly caused by the deposition of bismuth iodide (BiI3 )-doped solid-state electrolyte dielectrics. After synthetic optimization of dielectric compositions and semiconductor printing process, the flexible printed E-mode SWCNT TFTs show the high Ion /Ioff ratios of ≈106 , small subthreshold swing (SS) of 70-85 mV dec-1 , low operating voltages of ≈0.5 to -1.5 V, good stability and excellent mechanical flexibility during 10 000 bending cycles. E-mode N-type SWCNT TFTs are then selectively achieved via printing the polarity conversion ink (2-Amino-2-methyl-1-propanol (AMP)  as electron  doping agent) in P- type TFT channels. Last, printed SWCNT CMOS inverters are successfully constructed with full rail-to-rail output characteristics and the record unit static power consumption of 6.75 fW µm-1 at VDD of 0.2 V.

A universal roll-to-roll (R2R) printing approach was developed to construct large area (8 cm × 14 cm) semiconducting single-walled carbon nanotube (sc-SWCNT) thin films on flexible substrates (such as polyethylene terephthalate (PET), paper, and Al foils) at a printing speed of 8 m min-1 using highly concentrated sc-SWCNT inks and crosslinked poly-4-vinylphenol (c-PVP) as the adhesion layer. Bottom-gated and top-gated flexible printed p-type TFTs based on R2R printed sc-SWCNT thin films exhibited good electrical properties with a carrier mobility of ∼11.9 cm2 V-1 s-1, Ion/Ioff ratios of ∼106, small hysteresis, and a subthreshold swing (SS) of 70-80 mV dec-1 at low gate operating voltages (±1 V), and excellent mechanical flexibility. Furthermore, the flexible printed complementary metal oxide semiconductor (CMOS) inverters demonstrated rail-to-rail voltage output characteristics under an operating voltage as low as VDD = -0.2 V, a voltage gain of 10.8 at VDD = -0.8 V, and power consumption as low as 0.056 nW at VDD = -0.2 V. To the best of our knowledge, the electrical properties of the printed SWCNT TFTs (such as Ion/Ioff ratio, mobility, operating voltage, and mechanical flexibility) and printed CMOS inverters based on the R2R printed sc-SWCNT active layer in this work are excellent compared to those of R2R printed SWCNT TFTs reported in the literature. Consequently, the universal R2R printing method reported in this work could promote the development of fully printed low-cost, large-area, high-output, and flexible carbon-based electronics.

High‐performance stretchable optoelectronic synaptic transistor arrays are key units for constructing and mimicking simulated neuromorphic vision systems. In this study, ultra‐low power consumption and low‐operation‐voltage stretchable all‐carbon optoelectronic synaptic thin film transistors (TFTs) using sorted semiconducting single‐walled carbon nanotubes (sc‐SWCNTs) modified with CdSe/ZnS quantum dots as active layers on ionic liquid‐based composite elastomer substrates are first reported. The resulting stretchable TFT devices show enhancement‐mode characteristics with excellent electrical properties (such as the record on/off ratios up to 10 5 , negligible hysteresis, and small subthreshold swing), excellent mechanical tensile properties (such as the only 12.4% and 6.4% degradations of the carrier mobility after 20% vertical and horizontal strain stretching), and optoelectronic synaptic plasticity (for the recognition of Morse codes) with ultra‐low power consumptions (15.38 aJ) at the operating voltage from −1 to 0.2 V. At the same time, the designed nonvolatile conductance of the stretchable SWCNT optoelectronic synapse thin film transistors (SSOSTFTs) stimulated by UV light and the bending angle are first used to simulate stretchable neuromorphic vision systems (including the functions of the crystalline lens and optic cone cells as bionic eyes) for detecting the atmospheric environment with a record accuracy of 95.1% as a bionic eye.

Flexible brain-inspired neuromorphic transistors are spring up in the scopes of artificial electronic skins and human-interactive electronics for wearable devices and robotic applications benefiting from the capability of synchronous recognition and processing of the external information. In this work, we reported the flexible printed single-walled carbon nanotube (SWCNT) synaptic thin film transistors (TFTs) with printed silver electrodes as source/drain and gate electrodes, and the solid state electrolyte blending ionic liquids with crosslinked-poly(4-vinylphenol) (c-PVP) as dielectric layers. Our flexible printed SWCNT synaptic transistors display excellent electrical properties, such as low operation voltages (between ±1 V), high on/off ratios (>106) and low off currents (∼10−12 A), as well good stability and good mechanical flexibility. These flexible printed SWCNT TFT devices can imitate some typical synaptic plasticities like excitatory postsynaptic current and paired-pulse facilitation. The results indicate that synaptic behaviors of flexible devices are related to weight concentrations of ionic liquids in ionic c-PVP insulators. Moreover, our synaptic transistors can imitate the olfactory neurons and show the inhibitory characteristic when triggered by under a series of electrical stimulations after exposure to NH3.

Flexible fully-printed single-walled carbon nanotube CMOS inverters with low operating voltage that exhibit excellent voltage gains, noise margins and static power consumption, and good mechanical flexibility have been achieved.

设计了一种多参数水质监测系统,它由可原位实时监测水质的多参数监测仪及远程监控中心组成.监测仪基于单片机和GP RS无线通讯模块,集成蓝藻荧光传感器、水温传感器及水体浊度传感器等,可实现长时间的现场水质监测,并可将数据无线传输到远程监控中心.实验表明,设计的水质监测仪对蓝藻浓度检测的线性相关系数达到了0.99,且成本低廉,运行性能可靠.远程监控中心可实时接收监测数据,并可远程控制监测仪的工作状态.

文中结合了柔性印刷电子技术与传统硅基电子技术优势,采用DA14580蓝牙模块、数字温度传感器TMP 100和心率传感器SON7015等元器件设计了一种柔性可弯曲的无线传输人体生理参数采集电路.通过优化导电银浆的设计,提高了柔性电路板的抗弯折性能;通过实验探索制作工艺,实现了柔性多层线路制备方法及其与硬质芯片的有效结合,最终制作出功能可靠、轻薄柔性的电子系统.该系统有望直接贴敷于皮肤表面,实时监测人体温度、心率等生理信号,并将信号实时的以蓝牙方式发送到手机显示端.该电路的信号监测对人体体温的分辨率为0.0625℃,心率差别在1次之内,其良好的可弯曲性能使其更适合应用在可穿戴电子产品中.

A printable elastic silver ink has been developed, which was made of silver flakes, dispersant, and a fluorine rubber and could be sintered at a low temperature. The printed elastic conductors showed low resistivity at 21 μΩ·cm, which is about 13.2 times of bulk silver (1.59 μΩ·cm). Their mechanical properties were investigated by bending, stretching, and cyclic endurance tests. It was found that upon stretching the resistance of printed conductors increased due to deformation and small cracks appeared in the conductor, but was almost reversible when the strain was removed, and the recovery of conductivity was found to be time dependent. Radio-frequency identification (RFID) tags were fabricated by screen printing the stretchable silver ink on a stretchable fabric (lycra). High performance of tag was maintained even with 1000 cycles of stretching. As a practical example of wearable electronics, an RFID tag was printed directly onto a T-shirt, which demonstrated its normal working order in a wearing state.

SID Symposium Digest of Technical PapersVolume 50, Issue S1 p. 107-107 Technical Sessions: Session 11: Flexible Electronics and Materials (E-paper and Flexible Displays) 11.1: Invited Paper: Roll-to-Roll Printed Flexible Electronics and Applications Weibing Gu, Weibing Gu Ningbo Flexo Electronics Technology Ltd., Ningbo, Zhejiang, ChinaSearch for more papers by this authorZheng Cui, Zheng Cui Printable Electronics Research Centre, Suzhou Institute of Nanotech and Nano-bionics, Chinese Academy of Sciences, Suzhou, 215123 PR ChinaSearch for more papers by this author Weibing Gu, Weibing Gu Ningbo Flexo Electronics Technology Ltd., Ningbo, Zhejiang, ChinaSearch for more papers by this authorZheng Cui, Zheng Cui Printable Electronics Research Centre, Suzhou Institute of Nanotech and Nano-bionics, Chinese Academy of Sciences, Suzhou, 215123 PR ChinaSearch for more papers by this author First published: 04 October 2019 https://doi.org/10.1002/sdtp.13403AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume50, IssueS1International Conference on Display Technology (ICDT 2019)September 2019Pages 107-107 RelatedInformation

Figure of merit (FOM), the ratio of electrical conductance to optical transparency, is an important metric to evaluate transparent conductive film (TCF). The conductivity of commonly used flexible TCF such as indium tin oxide is generally limited and their FOM is lower than 300. In this study, a high‐performance copper (Cu) metal‐mesh TCF with the highest FOM ever reported, up to 8 × 10 4 , is fabricated through an additive manufacturing process of blading a silver seed layer and selective electroplating of Cu. With this strategy, Cu metallic lines completely constrained in roll‐to‐roll imprinted microgrooves achieve high aspect ratio of 2 with 4 µm width and 8 µm depth, which has very clean and smooth edges. This embedded Cu metal mesh exhibits an ultralow sheet resistance down to 0.03 Ω □ −1 at 86% optical transmittance. It is demonstrated that the Cu metal mesh has remarkable mechanical flexibility, high environmental stability at high temperature and humidity, and durability over repeated heating cycles. The Cu metal mesh is employed as a flexible transparent heater to attach to the windshield of a car, showing rapid heating at low voltage and effective removal of snow.

目的:通过印刷法制作柔性U HF RFID标签,实现RFID标签的可拉伸性,将其应用到可穿戴电子领域.方法:通过ADS仿真分析和公式计算两种方法得出RFID标签芯片的输入阻抗,并根据标签芯片的输入阻抗值用H FSS设计出一款基于半波偶极子天线的U H F RFID标签天线,最后通过印刷法制作出了可拉伸RFID标签实物.结果:UHF RFID标签天线的中心频率为890 MHz,在全频带(860～960 MHz)范围内的S11小于-10 dB,符合设计要求.结论:柔性可拉伸RFID标签测试结果与仿真结果一致,且在反复拉伸1000次后仍能保持将近7 m的读取距离,故可以应用于可穿戴电子领域.

Designing artificial muscle actuators with diversely complex deformation and multifunction is crucial to the soft robots and their bioinspired applications. Herein, by combing the hygroexpansion and thermal expansion commonly existed in nature, electrically driven paper‐based bilayer actuator is fabricated by a simple printing method. This actuator exhibits large (270°) and anisotropic deformation coupled with features of low‐cost, superior stability, and additional reversible color‐change function. More importantly, the tailoring and heat setting are used to further design the actuator shape, thus obtain multiform deformation (bending, elongation, and folding), and more complicated deformation similar to the arm motion. Based on these actuators, variously bioinspired motions can be constructed. Inspired by the structure of the crystalline lens and ciliary muscle in human eyeball, a biomimetic lens which can change the focal length under electrical stimulation is fabricated. Moreover, W‐shaped robotic arm for manipulating microliquid in 3D direction and catapulting the object into air, in‐pipe spiral robotic arm for pushing objects out of the pipe, and artificial snake capable of deformation and color‐change simultaneously, are also fabricated. This paper‐based actuator together with bioinspired design may open new perspective on the multifunctional smart robots and biomimetic devices.

Near infrared(NIR) sintering technology is a photonic sintering approach for metal nanoparticle inks, which can selectively sinter metal nanoparticle inks more quickly and efficiently, and it is also compatible with high-throughput manufacturing processes. In this paper, silver nanoparticle (AgNP) ink sintered by near infrared light at a peak wavelength of 1100 nm was investigated. After only 8 seconds of exposure to NIR irradiation, resistivity of 2.78 μΩ cm was achieved for thin films printed with AgNP ink, which was only 1.7-fold higher than that of bulk silver (1.59 μΩ cm). The structure of the sintered silver film was examined by sintering printed silver nanoparticle ink samples having different thicknesses, and the results showed that AgNPs were homogeneously coalesced throughout the cross-sections of films, indicating the formation of dense silver layers. Furthermore, the morphology and electrical resistivity of the sintered AgNP film dried by NIR were compared with those of the film dried on a hot plate. It was found that drying conditions with a relatively long drying time rather than the drying temperature contributed to the reduction of voids in the film and to the improvement in its density and electrical performance. Finally, a flexible hybrid circuit integrated with a microcontroller chip on a poly(ethylene terephthalate)(PET) substrate was fabricated by screen printing with AgNP ink for interconnects, and its surface roughness and flexibility were investigated.

In this paper, a flexible and stretchable circuit has been fabricated by the printing method based on Ag NWs/PDMS composite. The randomly oriented Ag NWs were buried in PDMS to form a conductive and stretchable electrode. Stable conductivity was achieved with a large range of tensile strain (0-50%) after the initial stretching/releasing cycle. The stable electrical response is due to the buckling of the Ag NWs/PDMS composite layer. Furthermore, printed stretchable circuits integrated with commercial ICs have been demonstrated for wearable applications.

A high sensitivity formaldehyde sensor was designed and fabricated based on nano-material of NiO and screen printing technology.With high specific surface area of the sensitive material,the sensor can detect formaldehyde gas even at ppb level.Furthermore,a smart multi-parameter air quality monitor that can wirelessly communicate with external device was developed based on STM8S208 and Bluetooth module,and integrated with PM2.5 sensor,VOC sensor,temperature and humidity sensor.Ex-periments show that the results are accurate and stable,and the monitor is suitable to be used as an air quality monitoring node in smart home system with low cost.

In this work, we reported a valid method to sort large‐diameter semiconducting single‐walled carbon nanotubes (sc‐SWCNTs) from commercial arc discharge SWCNTs by different conjugated organic compounds. Seven kinds of high‐purity sc SWCNT inks were achieved. As‐prepared sc‐SWCNT inks were directly used to fabricate printed SWCNT TFT arrays and backplane circuits on rigid substrates. It was found that printed SWCNT TFT devices exhibited high‐performance with low operating voltage (±2 V), small subthreshold swing (ss), small hysteresis, high mobility (more than 20 cm2 /Vs) and high on/off ratios (up to 106 ). Printed 2T‐1C driving circuit exhibited high on/off ratio up to 105 and high output current up to 8×10‐5 μ A at Vdata, Vscan and Vdd of ‐2 V, respectively. Furthermore, 15×15 OLED pixel arrays were switched on with printed SWCNT driving circuits on glass substrates, suggesting printed SWCNT driving circuits have the potential as backplanes for active matrix OLED applications.

A direct inkjet printing process was developed to fabricate patterned elastic microstructures for pressure sensors using n-butyl acetate diluted polymethylsiloxane (PDMS). The diluted PDMS precursor mixture with a cross-linker exhibited a controllable viscosity below 14 cP in 48 h at 25 °C, and the PDMS film had lower elastic modulus and hardness values than the non-diluted PDMS precursor after curing. The capacitor using the printed PDMS film as the microstructured dielectric layer showed a very high pressure sensitivity of up to 10.4 kPa−1 under the pressure below 70 Pa, and the pressure sensitivity would be dramatically decreased to 0.043–0.052 kPa−1 under the pressure between 2 and 8 kPa. Furthermore, the triboelectric sensors could be structured with an inkjet printed PDMS film and controllably generate the voltage signals up to 1.23 V without any amplification. The results suggest that mechanical properties and patterned elastic microstructures play the key roles in PDMS-based sensor devices, and the PDMS dielectric layer with controlled mechanical properties and microstructures fabricated via directly inkjet printing opens up the applications of the PDMS and its composites in functional devices.