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In the context of human active response to exponentially increasing data volumes, memristors have emerged as a focal point in systematic problem‐solving approaches. Particularly, organic memristors, characterized by excellent scalability, flexibility, and 3D stacking capabilities, have shown its tremendous potential in innovative electronic applications. However, the modulation of molecular assembly and interface interaction at the electrode surface poses a challenging task, despite their crucial role in determining the memristive performance. Herein, a collaborative method involving hydrophobic molecular design and interface engineering is proposed to generate high‐quality nanofilms with optimal photoelectric and electrochemical properties. By subjecting the bottom electrode to O2 plasma treatment and chemical modification using a hydrophobic ionic liquid poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide (PTFSI), the hydrophobic compound DN demonstrates exceptional affinity and stronger intermolecular interactions with the electrode surface. Consequently, the two‐terminal device array comprising Al/DN@PTFSI/ITO exhibits robust non‐volatile write‐once‐read‐many times (WORM) memory behavior, resulting in a tripling production yield from 30% to 92% along with a lower threshold voltage of 1.5 V, higher ON/OFF current ratio of 103 and excellent stability. This study presents a versatile approach to optimize the film assembly and material/electrode interface, thereby accelerating the development of organic memristors toward future applications. [ABSTRACT FROM AUTHOR]

2D orthorhombic palladium diselenide is attracting rapidly increased interest by virtue of its fascinating physical properties and feasibility of phase transformation. However, it remains a major challenge to produce ultrathin PdSe2 through a facile chemical route and control phase transformation because of its anisotropic structure with strong interlayer coupling. Here, the efficient synthesis of few‐layer PdSe2 nanosheets with large sizes using an electrochemical exfoliation approach is reported. Upon thermal annealing at 300–350 °C, the as‐exfoliated PdSe2 nanosheets transform into metallic phase PdSe2‐x, as verified by scanning transmission electron microscopy, Raman spectroscopy, and electrical characterizations. Simple encapsulation using hexagonal boron nitride (h‐BN) can effectively suppress the Se‐loss triggered phase transformation, so that a metal‐semiconductor junction is formed by local phase modification. The fabricated PdSe2 field‐effect transistors exhibit p‐type transport property, which is in stark contrast to electron‐dominated ambipolar transport of pristine PdSe2 devices. The combination of high‐resolution X‐ray photoelectron spectroscopy and cross‐sectional transmission electron microscopy analysis reveals that the modulation of carrier polarity in h‐BN encapsulated PdSe2 should arise from the p‐doping effect associated with the impact of interfacial condition. The study opens up a new route for future phase‐engineered electronics in PdSe2 and other 2D noble metal dichalcogenides materials. [ABSTRACT FROM AUTHOR]

The unique morphology of 2D van der Waals materials enables them to withstand large deformations and significant nonuniform strain, potentially inducing a strong flexoelectric effect. Despite the size‐dependent flexoelectric effect showing potential for modulating the optoelectronic performance of 2D van der Waals materials, it is far from being fully exploited owing to various challenges. Herein, the use of nanowires with different diameters as the bending media to fabricate 2D α‐In2Se3/β‐InSe heterojunctions with large curvatures of 0.1–1 µm−1 is proposed. The significant band alignment modulation in α‐In2Se3 resulting from the bending‐induced flexoelectric effect is verified through Kelvin probe force microscopy. The strain‐induced piezoelectric effect can be negated because of the weak vdW forces at the interface. The flexoelectric polarization in β‐InSe is screened via the accumulated electrons in the unilateral depleted heterojunction. Compared to the flat heterojunction, the curved heterojunction with an average curvature of 0.9 µm−1 shows 2.48‐fold and 7.62‐fold increases in open‐circuit voltage and zero‐biased responsivity, respectively. This study demonstrates the first successful modulation of photodetection in 2D heterojunctions by exploiting the flexoelectric effect, providing a new perspective for high‐performance 2D vdW optoelectronic devices. [ABSTRACT FROM AUTHOR]

Flexible electronics attract extensive interest in academic research and commercial markets. Fabrication of electronics on flexible substrates remains a great challenge though. Mostly, components of electronics including metal electrodes and functional materials are created via physical vapor deposition (PVD) in conjunction with photolithography. Nevertheless, ultrathin polymeric substrates are susceptible to environmental shocks during PVD. In this paper, a full‐solution process for fabricating copper (Cu) electrodes of micrometer (µm) scale on polymeric substrates is realized under ambient conditions via photolithography‐patterning polymer‐assisted metal deposition (pp‐PAMD). Apart from low fabrication costs from instruments capitals and energy inputs, these flexible Cu electrodes show superior mechanical durability. As a proof‐of‐concept application, large‐quantity and high‐quality indium selenide (InSe) nanoflakes, obtained by liquid electrochemical intercalation and ultrasonic exfoliation, are deposited on top of flexible Cu electrodes to construct all‐solution‐processed flexible photodetectors. The as‐fabricated flexible InSe photodetectors demonstrate excellent operational stability during 5000 continuous laser on‐off cycles, shelf stability under ambient storage conditions without encapsulation for 20 weeks, thermal viability from 90 to 360 K, and flexible stability upon mechanical bending at a radius (r) of 2 mm for 5000 cycles. This work implies the potential of pp‐PAMD technique and prospects of solution processes in fabricating flexible electronics. [ABSTRACT FROM AUTHOR]

Near infrared (NIR) photodetectors based on 2D materials are widely studied for their potential application in next generation sensing, thermal imaging, and optical communication. Construction of van der Waals (vdWs) heterostructure provides a tremendous degree of freedom to combine and extend the features of 2D materials, opening up new functionalities on photonic and optoelectronic devices. Herein, a type‐II InSe/PdSe2 vdWs heterostructure with strong interlayer transition for NIR photodetection is demonstrated. Strong interlayer transition between InSe and PdSe2 is predicted via density functional theory calculation and confirmed by photoluminance spectroscopy and Kelvin probe force microscopy. The heterostructure exhibits highly sensitive photodetection in NIR region up to 1650 nm. The photoresponsivity, detectivity, and external quantum efficiency at this wavelength respectively reaches up to 58.8 A W−1, 1 × 1010 Jones, and 4660%. The results suggest that the construction of vdWs heterostructure with strong interlayer transition is a promising strategy for infrared photodetection, and this work paves the way to developing high‐performance optoelectronic devices based on 2D vdWs heterostructures. [ABSTRACT FROM AUTHOR]

Expedited conversion of O2 to H2O with minimal amounts of Pt is essential for wide applicability of PEM fuel cells (PEMFCs). Therefore, it is imperative to develop a process for catalyst management to circumvent unnecessary catalyst loss while improving the Pt utilization, catalytic activity, and durability. Here, the fabrication of a self‐standing nanofiber electrode is demonstrated by employing electrospinning. This film‐type catalyst simultaneously contains Pt–Co alloy nanoparticles and Co embedded in an N‐doped graphitized carbon (Co–Nx) support derived from the electrospun zeolitic imidazolate frameworks. Notably, the flexible electrode is directly transferrable for the membrane‐electrode assembly of high temperature PEMFC. In addition, the electrodes exhibit excellent performance, maybe owing to the synergistic interaction between the Pt–Co and Co–Nx as revealed by the computational modeling study. This method simplifies the fabrication and operation of cell device with negligible Pt loss, compared to ink‐based conventional catalyst coating methods. [ABSTRACT FROM AUTHOR]

Designing high‐activity catalysts and revealing the in‐depth structure–property relationship is particularly important for Li–O2 batteries. Herein, the self‐boosting catalysis of LiCoO2 as an electrocatalyst for Li–O2 batteries and the investigation of its self‐adjustment mechanism using in situ X‐ray absorption spectroscopy and other operando characterization techniques is reported. The intercalation/extraction of Li+ in LiCoO2 not only induces the change in Co valence and modulates the electronic/crystal structure but also tunes the surface disorder degree, lattice strain, and local symmetry, which all affect the catalysis activity. In a discharge, highly ordered LiCoO2 acts as a catalyst to boost oxygen reduction reaction. During charging, the initial extraction of Li+ from LiCoO2 induces Li/oxygen vacancy and Co4+, which deforms CoO6 octahedron as well as lowers the symmetry, and accordingly promotes oxygen evolution reaction. This article offers insights into tuning the activity of catalysts for Li–O2 batteries with the intercalation/extraction of alkali metal ions in traditional cathodes. [ABSTRACT FROM AUTHOR]