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Highly stable and patterned silver nanowire (AgNW) networks are essential and challenging for flexible or wearable electronics. In this work, TiO2 coatings by atomic layer deposition (ALD) technique were introduced for the fabrication of highly stable and patterned AgNW/TiO2 composites for flexible transparent conductive electrodes (TCEs). It was found that TiO2 coating could not only enhance the adhesion of AgNWs to the substrate, but also improve the flexibility of AgNW networks. This phenomenon was owed to the stability enhancement by the three-dimensional conformal deposition of TiO2 coatings. What's more, the thermal and oxidation stabilities of AgNW networks could be greatly improved because of the barrier performance of TiO2 coating layer. Based on the stability enhancement by TiO2 coatings, a novelty patterning method of the AgNW networks was implemented by cooperating with photolithography and ultrasonic concussion process. AgNW networks with the strip width of 200 μm were well patterned without defects. Finally, highly stable and patterned AgNW/TiO2 composites were applied as flexible TCEs for alternating current electroluminescent (ACEL) devices. The whole ACEL device showed a high transparency of around 40%, and the flexibility and the lifetime of ACEL devices were correspondingly improved owe to the enhancement by TiO2 coatings. These results indicated the prospects of the AgNW/TiO2 composites on the applications to flexible or wearable electronics. TiO2 coatings by atomic layer deposition (ALD) technique were introduced for the fabrication of highly stable and patterned AgNW/TiO2 composites for flexible transparent conductive electrodes (TCEs). [ABSTRACT FROM AUTHOR]

Recently, artificial neurons have attracted much attention due to their excellent energy efficiency and scalability. However, there are still few reports on the regulation of the performance of artificial neuron based on single device. In the letter, we present an artificial neuron device based on Ag/TaOx/Si that not only has excellent turn-on and turn-off performance, but also exhibits sustained stability under multiple cycle tests. Moreover, the Integrate -and-Fire (IF) neuron model is successfully simulated at room temperature. More importantly, we find that an increase of temperature could reduce the threshold voltage and reset voltage of neurons, improve the probability of neuronal firing, and promote the transformation of neurons from nonvolatile to volatile. This work provides an effective method for regulating artificial neurons and has important implications for studying information transfer in biology and adapting complex computations in a memory computing framework. [ABSTRACT FROM AUTHOR]

Since the luminance of Micro-LEDs is highly dependent on the injected current density, inevitable voltage fluctuations will lead to luminance fluctuations and weak luminance robustness. In this work, Micro-LED chips working in non-electrical contact and non-carrier injection (NEC and NCI) mode is proposed, which is totally different from the current-injected mode. The luminance of NEC and NCI Micro-LEDs first increases with the increase of the voltage, and the saturation luminance can be obtained during a relatively large voltage range, which is defined as an operating voltage window. Then the luminance decreases when the voltage is further increased. It is demonstrated that the operating voltage windows can enhance luminance robustness. Finally, the insulating layer that is crucial for the operating voltage windows is optimized. And the working mechanisms related to the existence of operating voltage windows are discussed. [ABSTRACT FROM AUTHOR]

A noise detection system (INDS) composed of an acoustic triboelectric nano-generator (TENG) and an electrical bilayer synaptic transistor (EDLT) is proposed. As a self-powered sound sensor, TENG converts the sound signal directly into a voltage signal output. EDLT is used as a neuromorphic device to simulate synaptic behavior in organisms and has the ability to store and process signals simultaneously. In this letter, a kind of intelligent, simple structure and humanized noise detection system is developed. [ABSTRACT FROM AUTHOR]

Memristors based on organic–inorganic halide perovskite have received intensive attention because of its solution-processability and defect-tolerant characteristics. But the lead element in perovskite is inevitably harmful to human body and environment. Herein, we report an e-synapse based on lead-free organic halide perovskite (CH3NH3)3Sb2Cl9 (MA3Sb2Cl9), which exhibits excellent mimic of biological synaptic characteristics, such as excitatory postsynaptic currents (EPSCs), inhibitory postsynaptic currents (IPSCs), and paired-pulse facilitation (PPF). Furthermore, the synaptic weight of the e-synapse is found to be dependent on the frequency of pulse stimulation. The charge conduction mechanism of the e-synapse is proposed based on the in-depth investigation of the electrical characteristics of the devices. This work demonstrates that lead-free organic perovskite MA3Sb2Cl9 provide a new perspective on engineering e-synapses for neuromorphic computing and have a great potential for environment-friendly artificial intelligence applications. [ABSTRACT FROM AUTHOR]

Noncarrier injection (NCI) mode is an emerging driving mode for nanoscale light-emitting diodes (LEDs). Here, we demonstrate that a single light pulse from NCI-LEDs can be split into multiple pulses with small pulse widths that cannot be obtained by using traditional driving technology. Light-pulse splitting is achieved by using a combined signal that is a superposition of a basic signal and a signal with small amplitude and high frequency. Theoretical equations regarding the conduction current and current-pulse splitting are provided to explain light-pulse splitting theoretically. Then, light-pulse splitting is experimentally proven with a capacitor–LED–capacitor construction that is used to simulate the luminescence in NCI mode physically. Finally, we demonstrate light-pulse splitting from nanorod GaN-LEDs and discuss the working mechanisms related to electron multiple-frequency oscillation. This work can deepen the understanding of the NCI mode and provides a potential approach for advanced light-pulse-based technology. [ABSTRACT FROM AUTHOR]

In this paper, a novel vertical phototransistor was reported and compared with planar phototransistors for the first time. As compared with the planar phototransistors, the vertical ones exhibited much better photoelectric performance, which is attributed to an ultrashort photo-generated holes transfer distance and a stronger excitons dissociating electrical field due to their ultrashort channel length (tens of nanometers). Moreover, in order to examine the transport and trapping of different carrier charges separately, the impact of [6,6]-phenyl C61-butyric acid methyl ester (PCBM) dopant on the performance of planar and vertical phototransistors was investigated. The vertical devices exhibited an ultrahigh responsivity (~6600 A/W) as well as an excellent detectivity ($\sim 7\times 10^{15}~\text{Jones}$) and a fast photoresponse (rise time of 0.28 s), whereas slight changes were observed in the planar ones with doping of PCBM. The high performance of the blend vertical phototransistors is due to the trapping of the photo-generated electrons with PCBM and the effective transport of holes due to the ultrashort channel length. This paper provided a promising pathway for low-cost, high-performance phototransistors. [ABSTRACT FROM AUTHOR]

The electrical properties of a resistive-switching memory based on a single graphene sheet suspended on a patterned indium-tin-oxide electrode pair were investigated. Current-voltage measurements on the planar device showed a large ON/OFF ratio (∼106) and excellent retention ability in ambient conditions. Data storage of the device can be realized by applying voltage bias and rewritten after simple heat treatment. Switching mechanisms for the graphene-based memory device were found to be related to the local oxidation of graphene sheet at the graphene/electrode interface. [ABSTRACT FROM AUTHOR]

Non-volatile memory (NVM) devices using graphene quantum dots (GQDs) as charge trapping sites were fabricated with silver nanowires as top electrodes using solution process. The stacking structure consists of GQDs embedded between polymethylsilsesquioxane layers constructed on transparent flexible substrate. Hysteresis window was observed in the current–voltage plots, and the NVM devices are reprogrammable and stable up to 1\times 10^4 s with a distinct ON/OFF ratio of 10^4 . In addition, the memory device shows the stable hysteresis window without obvious degradation upon bending under different curvature radii. [ABSTRACT FROM PUBLISHER]

Abstract: Three-layer structured hybrid bistable devices (HBDs) utilizing graphene sheets sandwiched between polymer layers were fabricated by laminating two glass substrates coated with patterned electrodes and spacers. The hybrid devices using polystyrene (PS) and poly(vinyl-carbazole) (PVK) as matrix layer for graphene sheets demonstrated write-once-read-many-time and volatile memory effects, respectively. It is found that the memory properties of the HBDs can be tailored by varying the depth of the charge traps formed between the polymer matrix and graphene sheets. The possible operating mechanisms of the HBDs were analyzed based on the investigation of current–voltage characteristics for the hybrid devices. [Copyright &y& Elsevier]

In this paper, we reported a low temperature processed planar heterojunction perovskite solar cell employing silver nanowires as the top electrode and ZnO nanoparticles as the electron transport layer. The CH 3 NH 3 PbI 3 perovskite was grown as the light absorber via two-step spin-coating technique. The as-fabricated perovskite solar cell exhibited the highest power conversion efficiency of 9.21% with short circuit current density of 19.75 mA cm −2 , open circuit voltage of 1.02, and fill factor value of 0.457. The solar cell's performance showed negligible difference between the forward and reverse bias scan. This work paves a way for realizing low cost solution processable solar cells. [ABSTRACT FROM AUTHOR]

An electrically tunable large aperture liquid crystal (LALC) lens consisting of dual hole-patterned electrodes with different diameters is demonstrated. The proposed LALC lens can realize a tunable focal length and a switchable optical aperture by changing the driving models (DM). The experimental results show that the focal length of the LALC lens ranges from 325 mm to 220 mm when the operating voltage is changed from 24 V to 66 V by DM1, and it varies from 310 mm to 200 mm with the supplied voltages of 24–59 V by DM2. The optical aperture of the LALC lens can be switched between 4 mm-diameter and 5 mm-diameter. Furthermore, the turn-on time is significantly decreased by the over-driving method. Because of its low root mean square (RMS) error (<0.08 λ), the LALC lens, as an ideal optical lens, can exhibit excellent imaging performance in the optical imaging system. These results demonstrate that the proposed LALC lens has potential applications in the fields of imaging, biometrics and optical data storage because of its tunable focal length and switchable optical apertures. • The LALC lens with dual hole-patterned electrodes have been successfully fabricated. • The LALC lens can realize a switchable optical aperture by changing the driving models. • The LALC lens with tunable focal length and low RMS error is used as an ideal optical lens. • The proposed LALC lens has potential applications in the light field imaging system. [ABSTRACT FROM AUTHOR]

Abstract: Multilayer transparent electrode based on Al-doped zinc oxide (AZO)/Ag/Al-doped zinc oxide (AZO) was fabricated by sputtering, and a green organic light-emitting diode (OLED) device utilizing AZO/Ag/AZO as anode was fabricated. The AZO/Ag/AZO multilayer film exhibited superior square resistance and optical transmittance to those of commercial indium tin oxide (ITO). In comparison with the green OLEDs based on ITO and pure AZO anode, the green OLED based on AZO/Ag/AZO showed the highest light-emitting efficiency. The results indicate that AZO/Ag/AZO multilayer electrodes are a promising low-cost， low-toxic and low-temperature processing electrode scheme for OLED application. [Copyright &y& Elsevier]