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Mimicking the real‐time sensing and processing capabilities of human retina opens up a promising pathway for achieving vision chips with high‐efficient image processing. The development of retina‐inspired vision chip also requires hardware with high sensitivity, fast image capture, and the ability to sense under various lighting conditions. Herein, a high‐performance phototransistor based on graphene/organic heterojunction is demonstrated with a superior responsivity (2.86 × 106 A W−1), an outstanding respond speed (rise time/fall time is 20 µs/8.4 ms), and a remarkable detectivity (1.47 × 1014 Jones) at 650 nm. The phototransistor combines weak‐light detection capability (minimum detectable light intensity down to 2.8 nW cm−2) with gate‐tunable bi‐directional photoresponse capable of simultaneously sensing and processing visual images for light intensities ranging over six orders magnitude (10–107nW cm−2). Moreover, the phototransistor also exhibits an intriguing feature undiscovered in other retina‐inspired devices, namely that it can real‐time monitor the human pulse signal and heart rate by using photoplethysmography technology, and the measured heart rate error is only 0.87% compared with a commercially available sensor. This study paves the way for the development of low‐light and bio‐signal sensitive artificial retinas in the future. [ABSTRACT FROM AUTHOR]

Optoelectronic synaptic devices, which combine the functions of photosensitivity and information processing, are essential for the development of artificial visual perception systems. Nevertheless, improving the paired pulse facilitation (PPF) index of optoelectronic synaptic devices, which is an urgent problem in the construction of high‐precision artificial visual perception systems, has received less attention so far. Herein, a light‐stimulated synaptic transistor (LSST) device with an ultra‐high PPF index (≈196%) is presented by introducing an ultra‐thin carrier regulator layer hexagonal boron nitride (h‐BN) into a classic graphene‐based hybrid transistor frame (graphene/CsPbBr3 quantum dots). Crucially, analysis of the rate‐limiting effect of h‐BN on photogenerated carriers reveals the mechanism behind the LSST ultra‐high PPF index. Furthermore, a two‐layer artificial neural network connected by LSST devices demonstrate ≈91.5% recognition accuracy of handwritten digits. This work provides an effective method for constructing artificial visual perception systems using a hybrid transistor frame in the future. [ABSTRACT FROM AUTHOR]

Furthermore, the benefit from the outstanding photoelectric detection performance of the device, real-time pulse signals, and heart rate monitoring applications are explored and realized. Keywords: gate-tunable bi-directional photoresponses; graphene/organic phototransistors; in-chip processing; pulse monitoring; weak-light detection EN gate-tunable bi-directional photoresponses graphene/organic phototransistors in-chip processing pulse monitoring weak-light detection 1 1 1 12/27/22 20221222 NES 221222 B Graphene/Organic Hybrid Phototransistor b In article number 2209680, Jun Wang, Xianchao Liu, and co-workers present a graphene/organic hybrid phototransistor with a novel gate-tunable bi-directional photoresponse capable of simulating visual preprocessing of the human retina. High-Performance Phototransistor Based on Graphene/Organic Heterostructure for In-Chip Visual Processing and Pulse Monitoring (Adv. Funct. [Extracted from the article]

Artificial neural network, hexagonal boron nitride, light-stimulated synaptic transistors, paired pulse facilitation index, visual perception system Keywords: artificial neural network; hexagonal boron nitride; light-stimulated synaptic transistors; paired pulse facilitation index; visual perception system EN artificial neural network hexagonal boron nitride light-stimulated synaptic transistors paired pulse facilitation index visual perception system 1 1 1 05/30/22 20220525 NES 220525 B Light-Stimulated Synaptic Transistors b Optoelectronic synaptic devices with a high paired pulse facilitation index are essential for constructing high-precision artificial visual perception systems. Light-Stimulated Synaptic Transistor with High PPF Feature for Artificial Visual Perception System Application (Adv. Funct. [Extracted from the article]

Anode‐free sodium metal batteries (AFSMBs) as one new battery configuration, have attracted more attention in recent years and considered as the promising next‐generation energy storage systems, owing to the advantages of high theoretical energy density, high safety, cost‐saving, and simplified fabrication process. The practical application of AFSMBs, however, is impeded by their poor cycle life arising from the low coulombic efficiency (CE), the growth of metal dendrite, and unstable solid electrolyte interphase (SEI). Recently, some works are reported to dissolve the above‐mentioned issues. In this review, it provides a comprehensive summary of AFSMBs including their origin, mechanism, advantages, challenges, strategies, and perspectives. First, the intrinsic issues of conventional sodium metal batteries are summarized as safety concerns and manufacturing difficulty, which is the background of promoting AFSMBs' birth. Subsequently, the mechanism, construction requirement, advantages, and challenges of AFSMBs are discussed. Furthermore, the strategies for improving AFSMBs performance in terms of the current collector, electrolyte, and protocols, are summarized based on an extensive literature survey. Finally, the summary and outlook on this emerging field are further discussed briefly. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐ion batteries with mild acidic electrolytes are considered the promising energy storage solutions due to their outstanding merits of high energy density and cost‐effectiveness. However, the rampant dendrite growth and severe parasitic reactions caused by a series of factors such as irregular Zn2+ transport pathway and pH variation would result in poor cycling stability. Herein, a self‐regulated interface strategy implemented by ammonium persulfate ((NH4)2S2O8, denoted as APS) multifunctional additive is proposed to simultaneously address the above issues. The zincophilic NH4+ preferentially adsorbs on the Zn protuberance to exclude water molecules and shield the "tip effect," thus inhibiting side‐reactions and inducing uniform Zn deposition. Moreover, NH4+ and S2O82− can dynamically adjust H+ and OH− concentrations in a pH self‐buffer manner, thus effectively mitigating hydrogen evolution reaction and formation of by‐products. Consequently, with the existence of APS additive, Zn anode exhibits ultrahigh coulombic efficiency (CE) of 99.9% over 9000 cycles and ultra‐long lifespan of 4300 h at 5 mA cm−2. Furthermore, even under high NH4V4O10 mass loading (9.4 mg cm−2) and thin zinc foil (10 µm), the assembled NH4V4O10//Zn pouch cell with APS additive can still maintain stably over 210 cycles, demonstrating its excellent value for application. [ABSTRACT FROM AUTHOR]

Dendritic growth and severe side reactions remain challenging problems for advancing aqueous zinc‐ion batteries. Those critical issues are closely related to the interfacial chemistry, solvation structure, and transportation kinetics of zinc ions. Herein, a regulated ion‐conductive electrode–electrolyte interface (PVA‐Zn(CF3SO3)2‐Si3N4, denoted as PZS) on Zn metal has been in situ constructed, which simultaneously solves the above‐mentioned issues. PZS can effectively accelerate ion transportation and extrude interfacial water, thus endowing dendrite‐free Zn deposition and eliminating side reactions. Benefiting from these features, the PZS‐Zn exhibits stable and reversible Zn stripping/plating with an ultralong cycling life of 3800 h, and an ultrahigh Coulombi efficiency of 99.8%. The full cell paired with the NH4V4O10 cathode runs stably over 1000 cycles at 5 A g−1 with near 100% capacity retention and is demonstrated to cycle up to 200 times along with 71.94% capacity retention in a practical cathode‐anode coupling configuration pouch cell. With this interfacial design, the assembled zinc batteries display excellent cycling stability, paving a practical way for aqueous Zn‐storage systems. [ABSTRACT FROM AUTHOR]

Lithium metal anodes are promising for application in new‐type secondary batteries. Unfortunately, low cycle life and safety peril induced by uncontrollable dendrites growth and weak solid electrolyte interface (SEI) have blocked their utilization. In this work, an interlamellar lithium‐ion conductor of lithium‐montmorillonite (Li‐MMT) is applied to enhance the SEI properties, inhibit dendrites‐germination, and thus significantly enhance electrochemical performance. Such a well‐designed Li‐MMT SEI not only possesses inherent fast lithium‐ion channels, but also works as a reservoir to supply adequate lithium‐ions in the interlaminations and periphery of Li‐MMT nanosheets, offering fast lithium‐ion transfer in interlaminations and sheet‐to‐sheet. Furthermore, the strong trend of lithium‐ion absorption of Li‐MMT is confirmed by density functional theory calculations and stable lithium deposition under Li‐MMT SEI layer at 10 mA cm−2 is verified via finite element modeling. As a result, a steady lithium deposition process without dendrites is achieved. Coulombic efficiency of the half‐cell accomplishes a mean value of 99.1% over 400 cycles at 1 mA cm−2, while Li‐LiFePO4 full cells show a stable capacity up to 120 mAh g−1 and steady circulation over 400 loops at 1C. This work offers a novel strategy to design a high‐performance SEI layer and suppress dendrite growth. [ABSTRACT FROM AUTHOR]

Realizing compact dendrite‐free zinc (Zn) plating is crucial to avoiding premature battery failure caused by internal short‐circuits, which is highly determined by the interface electric field (ψi) distribution. Herein, a concept of "potential compensating" is shown on Zn anodes to stimulate its self‐smoothing deposition behavior for durable batteries. A homogeneous ψi with elevated potential intensity is successfully built at the Zn/electrolyte interface via the selective adsorption of highly polarized propylene glycol (PG) molecules, which facilitate the formation of dense and uniform Zn electroplating patterns. Moreover, the PG additive can simultaneously reshape the structure of Zn2+‐solvation sheath and immobilize the H‐bonding networks in bulk electrolyte, enabling Zn anodes with exceptional electrochemical reversibility (99.6%) and ultralong calendar life (3500 h), as revealed by joint spectroscopic and electrochemical analyses. More importantly, full cells with PG safeguard can deliver desirable cycling stability even at an elevated temperature (50 °C) and low N/P ratios (cathode mass loading up to 14.38 mg cm−2). This study presents new insight into the rational design of stable practical electrolytes and interfacial chemistry regulation for sustainable zinc batteries. [ABSTRACT FROM AUTHOR]

Bi‐directional photodetection with positive and negative photoconductance (PPC/NPC) plays a critical role in building next‐generation artificial neuromorphic systems, visual information processing and optoelectronic logic gates of the future. However, the typical device configuration based on heterostructures with strict working principles restricts the diversity of material selection. In this work, a novel strategy is proposed to fabricate bi‐directional photoresponse devices based on PtSe2−x films with precisely controllable selenization engineering. It is found that the PtSe2−x films are composed of Pt and PtSe2 components. The direction of the photocurrent can be reversibly modulated in a broadband range by tuning the ratio of PtSe2 in the film, which is ascribed to the synergistic mechanism of bolometric effect of Pt and photoconductive effect of PtSe2. The polarity switching wavelength from NPC to PPC can be further modulated through tuning the components of the film for specific demand. The tunable bi‐directional photoresponse enables the device to mimic the fundamental functions of artificial synapses all optically, such as aversion learning capability and logical functions, with high paired pulse facilitation index. This work potentially opens an opportunity for the development of advanced artificial neuromorphic systems and optoelectronic logic gates. [ABSTRACT FROM AUTHOR]

Bi-directional, photoresponse, selenization engineering, artificial synapses Keywords: artificial synapses; bi-directional; photoresponse; selenization engineering EN artificial synapses bi-directional photoresponse selenization engineering 1 1 1 08/29/22 20220825 NES 220825 B Tunable Bidirectional Photoresponses b In article number 2205709, Yulong Liao, He Yu, Jun Wang, and co-workers report the first observation of a tunable bidirectional photoresponse in hybrid PtSe SB 2- I x i sb films based on precisely controllable selenization engineering. Tunable Bi-directional Photoresponse in Hybrid PtSe2-x Thin Films Based on Precisely Controllable Selenization Engineering (Adv. Funct. [Extracted from the article]