Vertical transistors have attracted enormous attention in the next-generation electronic devices due to their high working frequency, low operation voltage and large current density, while a major scientific and technological challenge for high performance vertical transistor is to find suitable source electrode. Herein, an MXene material, Ti3C2Tx, is introduced as source electrode of organic vertical transistors. The porous MXene films take the advantage of both partially shielding effect of graphene and the direct modulation of the Schottky barrier at the mesh electrode, which significantly enhances the ability of gate modulation and reduces the subthreshold swing to 73 mV/dec. More importantly, the saturation of output current which is essential for all transistor-based applications but remains a great challenge for vertical transistors, is easily achieved in our device due to the ultra-thin thickness and native oxidation of MXene, as verified by finite-element simulations. Finally, our device also possesses great potential for being used as wide-spectrum photodetector with fast response speed without complex material and structure design. This work demonstrates that MXene as source electrode offers plenty of opportunities for high performance vertical transistors and photoelectric devices.

Organic field-effect transistor (OFET) memory has received widespread attention due to its easy integration, precise charge modulation, and multi-level memory. However, the performance of organic memory still needs to be improved for its practical application, and the reported technologies are strongly dependent on an additional charge-trapping layer, which increases the complexity of the device. Here, we report a heterostructured vertical organic memory transistor, which uses a p/n semiconductor bulk heterojunction as a semiconductor layer without using any additional charge-trapping layers. The device exhibits a large memory window of 52 V, and the memory ratio reaches 10 5 through electrical operation. Benefiting from the formation of the p/n semiconductor interface and the nanometer-scale transmission length, under the stimulation of visible light, the device achieved a 58 V memory window, high memory ratio 10 5 , and retention characteristics of over 10 years, which is better than those of most reported optical organic memory devices. More interestingly, we found that as the level of the doping in the n-type semiconductor increased, the device could transform from nonvolatile memory to artificial synapse, which is associated with the morphology of a heterojunction structure. Hence, we demonstrate a novel technique to manufacture high-performance nonvolatile optoelectronic memory and artificial synapse, which shows great potential in OFET-based memory and neuromorphic devices.

Devices with sensing-memory-computing capability for the detection, recognition and memorization of real time sensory information could simplify data conversion, transmission, storage, and operations between different blocks in conventional chips, which are invaluable and sought-after to offer critical benefits of accomplishing diverse functions, simple design, and efficient computing simultaneously in the internet of things (IOT) era. Here, we develop a self-powered vertical tribo-transistor (VTT) based on MXenes for multi-sensing-memory-computing function and multi-task emotion recognition, which integrates triboelectric nanogenerator (TENG) and transistor in a single device with the simple configuration of vertical organic field effect transistor (VOFET). The tribo-potential is found to be able to tune ionic migration in insulating layer and Schottky barrier height at the MXene/semiconductor interface, and thus modulate the conductive channel between MXene and drain electrode. Meanwhile, the sensing sensitivity can be significantly improved by 711 times over the single TENG device, and the VTT exhibits excellent multi-sensing-memory-computing function. Importantly, based on this function, the multi-sensing integration and multi-model emotion recognition are constructed, which improves the emotion recognition accuracy up to 94.05% with reliability. This simple structure and self-powered VTT device exhibits high sensitivity, high efficiency and high accuracy, which provides application prospects in future human-mechanical interaction, IOT and high-level intelligence.

Selective attention is an efficient processing strategy to allocate computational resources for pivotal optical information. However, the hardware implementation of selective visual attention in conventional intelligent system is usually bulky and complex along with high computational cost. Here, programmable ferroelectric bionic vision hardware to emulate the selective attention is proposed. The tunneling effect of photogenerated carriers are controlled by dynamic variation of energy barrier, enabling the modulation of memory strength from 9.1% to 47.1% without peripheral storage unit. The molecular polarization of ferroelectric P(VDF-TrFE) layer enables a single device not only multiple nonvolatile states but also the implementation of selective attention. With these ferroelectric devices are arrayed together, UV light information can be selectively recorded and suppressed the with high current decibel level. Furthermore, the device with positive polarization exhibits high wavelength dependence in the image attention processing, and the fabricated ferroelectric sensory network exhibits high accuracy of 95.7% in the pattern classification for multi-wavelength images. This study can enrich the neuromorphic functions of bioinspired sensing devices and pave the way for profound implications of future bioinspired optoelectronics.

RNF8 (ring finger protein 8), a RING finger E3 ligase best characterized for its role in DNA repair and sperm formation via ubiquitination, has been found to promote tumor metastasis in breast cancer recently. However, whether RNF8 also plays a role in other types of cancer, especially in the lung cancer, remains unknown. We show here that RNF8 expression levels are markedly increased in human lung cancer tissues and negatively correlated with the survival time of patients. Overexpression of RNF8 promotes the EMT process and migration ability of lung cancer cells, while knockdown of RNF8 demonstrates the opposite effects. In addition, overexpression of RNF8 activates the PI3K/Akt signaling pathway, knockdown of RNF8 by siRNA inhibits this activation, and pharmacological inhibition of PI3K/Akt in RNF8 overexpressing cells also reduces the expression of EMT markers and the ability of migration. Furthermore, RNF8 is found to directly interact with Slug and promoted the K63-Ub of Slug, and knockdown of Slug disrupts RNF8dependent EMT in A549 cells whereas overexpression of Slug rescues RNF8-dependent MET in H1299 cells. And depletion of RNF8 expression by shRNA inhibits metastasis of lung cancer cells in vivo. Taken together, these results indicate that RNF8 is a key regulator of EMT process in lung cancer and suggest that inhibition of RNF8 could be a useful strategy for lung cancer treatment. Implications: This study provides a new mechanistic insight into the noval role of RNF8 and identifies RNF8 as a potential new therapeutic target for the treatment of lung cancer.

addressing probabilistic, and unstructured problems, thus is anticipated to solve the von Neumann bottleneck and become the mainstay of contemporary computing systems. [1,2] Synapses serve a crucial function in signal transmission in the biological neural system. [3] They transmit signals through neurotransmitters in a manner similar to that of field-effect transistors, where source-drain current changing in response to changes in gate voltage. In addition, organic materials are solutionprocessable, [4][5][6][7] thus simulating the functions of biological synapses by organic field-effect transistors has received intensive attention. [8,9] Most recently, higher performance requirements for devices are put forward to support practical applications, including fast switching speed, low energy consumption, low operating voltage, and strong compatibility with flexible substrate. Traditional planar field effect transistors struggle to accomplish these functions. Conversely, vertical organic field-effect transistors (VOFETs) have a more stable sourcedrain current and a changeable channel length that depends Organic field-effect transistors with parallel transmission and learning functions are of interest in the development of brain-inspired neuromorphic computing. However, the poor performance and high power consumption are the two main issues limiting their practical applications. Herein, an ultralowpower vertical transistor is demonstrated based on transition-metal carbides/ nitrides (MXene) and organic single crystal. The transistor exhibits a high J ON of 16.6 mA cm −2 and a high J ON /J OFF ratio of 9.12 × 10 5 under an ultralow working voltage of −1 mV. Furthermore, it can successfully simulate the functions of biological synapse under electrical modulation along with consuming only 8.7 aJ of power per spike. It also permits multilevel information decoding modes with a significant gap between the readable time of professionals and nonprofessionals, producing a high signal-to-noise ratio up to 114.15 dB. This work encourages the use of vertical transistors and organic single crystal in decoding information and advances the development of low-power neuromorphic systems.

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Light‐stimulated optoelectronic synaptic devices are fundamental compositions of the neuromorphic vision system. However, there are still huge challenges to achieving both bidirectional synaptic behaviors under light stimuli and high performance. Herein, a bilayer 2D molecular crystal (2DMC) p‐n heterojunction is developed to achieve high‐performance bidirectional synaptic behaviors. The 2DMC heterojunction‐based field effect transistor (FET) devices exhibit typical ambipolar properties and remarkable responsivity (R) of 3.58×104 A W−1 under weak light as low as 0.008 mW cm−2. Excitatory and inhibitory synaptic behaviors are successfully realized by the same light stimuli under different gate voltages. Moreover, a superior contrast ratio (CR) of 1.53×103 is demonstrated by the ultrathin and high‐quality 2DMC heterojunction, which transcends previous optoelectronic synapses and enables application for the motion detection of the pendulum. Furthermore, a motion detection network based on the device is developed to detect and recognize classic motion vehicles in road traffic with an accuracy exceeding 90%. This work provides an effective strategy for developing high‐contrast bidirectional optoelectronic synapses and shows great potential in the intelligent bionic device and future artificial vision.