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Comprehensive Summary: Considering their oriented crystalline structure and high luminescent efficiency, the exploration of multi‐component organic cocrystal systems with tunable supramolecular nanostructures and potential RGB light emission has emerged as a captivating but challenging subject. Here, we propose a straightforward synthetic strategy to precisely govern the assembly, structure and structure‐property relationship of organic cocrystals. By employing the single‐crystalline template‐assisted epitaxial growth (SCT‐EG) method, the two‐dimensional (2D) highly‐aligned cocrystal nanomeshes are firstly developed to afford an exceptional RGB trichromatic system, triggering cross‐modulation white light emission (WLE) with remarkable stability and regeneration capacity over six months. The transformation from random 1D microstructures to uniformly‐oriented 2D nanomeshes can be attributed to the regulatory competitive intermolecular π‐π, CT interactions, and partial H bond interactions among cocrystals. Moreover, the successful construction of 2D RGB trichromatic cocrystal nanomeshes system holds promise to generate full‐color display, which can function as multicolor inks for photonic dynamic recognition, information encryption, and decryption. [ABSTRACT FROM AUTHOR]

The time‐dependent mechanism underlying the formation of Co0.8Fe0.2(OH)x‐t nanomesh (nanomesh having 80 % Co and 20 % Fe, “t” represents materials synthesis time) has been identified towards the development of a highly effective catalyst for the oxygen evolution reaction (OER). Utilizing 2‐ethyl imidazole (2‐HEIM) as an etching reagent and the Ostwald ripening process enabled the evolution of nanomesh formation with a precise pore size of ink‐bottle shape. Characterization techniques, including N2‐adsorption/desorption, and transmission electron microscopy (TEM) analyses, confirmed the evolution of pore structure from layered double hydroxide‐like structure to hierarchical slit‐pores to uniform ink‐bottle pores after 24 h of synthesis with limited pore shrinkage attributable to iron redeposition at the pore entrances. Atomic force microscopy (AFM) showed a gradual reduction in nanomesh thickness with an increase in synthesis time up to 24 h, indicative of successful exfoliation. The best catalyst (Co0.8Fe0.2(OH)x‐24 h) was developed after 24 h of synthesis, having 3.8 nm ink‐bottle‐shaped pores on the basal plane of nanosheets with only 3–4 layers. Co0.8Fe0.2(OH)x‐24 h nanomesh exhibited the best catalytic performance, characterized by a 330 mV overpotential, a mass activity of 309.1 A/g, and a turnover frequency of 2.28 s−1. Furthermore, electrochemical impedance spectroscopy indicated a low charge transfer resistance (5.9 Ω) and pseudoresistance (35.3 Ω), highlighting efficient electron transfer at the electrode/electrolyte interface and enhanced oxygen evolution reaction kinetics, respectively. An increased electrochemical surface area (70.74 cm2) and a high roughness factor of approximately 1010 underlined the importance of narrow mesopores in facilitating catalyst‐electrolyte interactions and improving mass transport. The best material demonstrated remarkable stability during 25 h of electrolysis with a high average current density of 14.5 mA/cm2. Hence, this research underscores the critical role of pore morphology in nanomeshes for optimizing catalytic performance and providing stability under vigorous gas evolution due to catalysis. [ABSTRACT FROM AUTHOR]

Flexible hydrogel film sensors have great advantages as human–machine interfaces for conformal contact with bio‐tissues, but suffer from weakness and dehydration, compromising flexibility and performance. Here, a breathable, highly stretchable, and anti‐dehydrating ultrathin organohydrogel film as a skin‐attachable strain sensor for long‐term motion monitoring is developed. An electrospun TPU (eTPU) nanomesh with hidden strength is used as skeleton to host in situ free radical polymerization of 2‐acrylamido‐2‐methyl propane sulfonic acid (AMPS) and acrylamide (AAm) to form an interpenetrating double network organohydrogel with glycerol and water as solvent. Extensive hydrogen bonding between eTPU nanomesh and P(AMPS‐co‐AAm) network yields ultrathin organohydrogel film (≈200 µm) with synergetic deformation and energy dissipation upon stretching, leading to record‐high stretchability up to 920%, fracture toughness of 20.14 MJ m−3, fracture energy of 10 000 J m−2, and robustness over 4000 notched stretching cylcles to 50% strain. The binary glycerol/water solvent imparts excellent anti‐dehydration at room temperature for 10 d, and stable sensory performance from −20 to 60 °C. With a high water vapor transmission rate of 1.3 kg m−2 d−1, the film sensor ensures comfortable skin contact for continuous knee flexion monitoring throughout the day with stable signals. These organohydrogel film strain sensors are promising for wearable and long‐term motion monitoring applications. [ABSTRACT FROM AUTHOR]

Touch serves as an important medium for human–environment interaction. The piezoresistive tactile sensor has attracted much attention due to its convenient technology, simple principle, and convenient signal acquisition and analysis. In this paper, conductive beads-on-string polyvinyl alcohol (PVA)/polyaniline doped with dodecyl benzene sulfonic acid (PANI-DBSA) nanofibers were fabricated via the electrospinning technique. Due to the special nanostructure of PVA-coated PANI-DBSA, the tactile sensor presented a wide measuring range of 12 Pa–121 kPa and appreciable sensitivity of 8.576 kPa−1 at 12 Pa~484 Pa. In addition, the response time and recovery time of the sensor were approximately 500 ms, demonstrating promising prospects in the field of tactile sensing for active upper limb prostheses. [ABSTRACT FROM AUTHOR]

• Addressing the restacking issue of MXene. • Pushing the theoretical proton storage limits of MXenes. • Enhancing ion transport rates in harsh environments. 2D MXenes have attracted great attention in portable flexible supercapacitors owing to their high volumetric capacitances, excellent electrical conductivity, tunable surface terminations, and good flexibility. However, the low gravimetric capacitances due to the tortuous ion transport in restacked nanosheets may limit the possible applications. Herein, we propose an atomic tailoring strategy to produce nitrogen-doped porous films assembled by Ti 3 C 2 T z MXene nanomesh. The introduced Ti-N-O/Ti-N-OH terminations greatly improve the electrochemical activity, and the rich in-plane pores in Ti 3 C 2 T z nanomesh provide abundant pathways and new active sites for ion transfer/adsorption. Benefiting these surface modifications and structural engineering, the obtained freestanding films achieve ultrahigh gravimetric and volumetric capacitances (700F g−1 or 2023F cm−3 at 1 A g−1) and superior rate performance (550F g−1 or 1860F cm−3 at 100 A g−1). When assembling into symmetric supercapacitors, high energy densities, and good cycling stability are achieved at room temperature and −40 °C, respectively, demonstrating great promise for practical applications. [ABSTRACT FROM AUTHOR]

We analyzed the structures formed by 3,3',5,5'-tetrabromobiphenyl (TBBP) on the Au(111) surface under ultra-high vacuum (UHV) conditions using scanning tunneling microscopy. TBBP, which contains two phenyls, is expected to form the same structure after combining with other molecules with different orientations. Islands composed of three types of dimers were obtained at room temperature. Annealing of the dimers at temperatures above 423 K formed a porous nanostructure with neighboring nanohole distances of 0.7 nm, consistent with our expectations. The porous nanostructure was composed of combinations of dimers with various orientations, indicating the flexibility of the precursor molecule in forming the obtained structure. [Display omitted] • Tetrabromobiphenyl molecules formed a porous nanostructure by orientation adaptation. • The molecules on Au(111) surface formed islands composed of three types of dimers without additional annealing. • The annealing time influenced the formation of oligomers. • Annealing at 423 K can balance the on-surface reaction and conformational changes. [ABSTRACT FROM AUTHOR]

Silicone-based devices have the potential to achieve an ideal interface with nervous tissue but suffer from scalability, primarily due to the mechanical mismatch between established electronic materials and soft elastomer substrates. This study presents a novel approach using conventional electrode materials through multifunctional nanomesh to achieve reliable elastic microelectrodes directly on polydimethylsiloxane (PDMS) silicone with an unprecedented cellular resolution. This engineered nanomesh features an in-plane nanoscale mesh pattern, physically embodied by a stack of three thin-film materials by design, namely Parylene-C for mechanical buffering, gold (Au) for electrical conduction, and Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) for improved electrochemical interfacing. Nanomesh elastic neuroelectronics are validated using single-unit recording from the small and curvilinear epidural surface of mouse dorsal root ganglia (DRG) with device self-conformed and superior recording quality compared to plastic control devices requiring manual pressing is demonstrated. Electrode scaling studies from in vivo epidural recording further revealed the need for cellular resolution for high-fidelity recording of single-unit activities and compound action potentials. In addition to creating a minimally invasive device to effectively interface with DRG sensory afferents at a single-cell resolution, this study establishes nanomeshing as a practical pathway to leverage traditional electrode materials for a new class of elastic neuroelectronics., (© 2024 Wiley‐VCH GmbH.)

Graphene has attracted wide attentions since its successfully exfoliation. Honeycomb sp 2 ) and argon (Ar) plasma. With different parameter and feeding gas, hydrogenated graphene, graphene nanomesh and graphene with vacancies can be well obtained. The defect density can be precisely controlled by tuning plasma power and irradiation time. Morphological, spectroscopic, and electrical characterizations are performed to systematically investigate the defect evolution. Graphene nanomesh and graphene with vacancies show obvious difference for roughness and coverage, whereas the morphology of hydrogenated graphene remains similar with that of as-prepared graphene. For hydrogenated graphene, an opened bandgap of ∼20 meV is detected. For graphene nanomesh and graphene with vacancies, the semiconductive on/off behaviors are observed. We believe this work can provide more details of plasma-induced defects and assist the application of graphene in semiconductor industry.2 ) and argon (Ar) plasma. With different parameter and feeding gas, hydrogenated graphene, graphene nanomesh and graphene with vacancies can be well obtained. The defect density can be precisely controlled by tuning plasma power and irradiation time. Morphological, spectroscopic, and electrical characterizations are performed to systematically investigate the defect evolution. Graphene nanomesh and graphene with vacancies show obvious difference for roughness and coverage, whereas the morphology of hydrogenated graphene remains similar with that of as-prepared graphene. For hydrogenated graphene, an opened bandgap of ∼20 meV is detected. For graphene nanomesh and graphene with vacancies, the semiconductive on/off behaviors are observed. We believe this work can provide more details of plasma-induced defects and assist the application of graphene in semiconductor industry., (© 2024 IOP Publishing Ltd.)

The merits of excellent electrical conductivity, good hydrophilicity, and large specific capacitances render MXene film electrodes attractive in supercapacitors (SCs). However, the tortuous ion transfer in restacked nanosheets limits the electrochemical performance of dense film electrodes. To solve the ion transfer issue, we propose a strategy to produce porous films assembled by Ti 3 C 2 nanomesh via the chemical oxidation-etching process. The rich in-plane pores in Ti 3 C 2 nanomesh provide abundant pathways and new active sites for ion transfer/adsorption, greatly improving the electrochemical activity. Specifically, the obtained Ti 3 C 2 nanomesh films exhibit high specific capacitances of 235 F g-1 at 1 A g-1 and 184 F g-1 at 10 A g-1 in 6 M KOH, which are ∼2 times higher than the pristine Ti 3 C 2 films (118 F g-1 at 1 A g-1 and 90 F g-1 at 10 A g-1). Furthermore, hybrid capacitors, composed of the Ti 3 C 2 nanomesh films as the negative electrodes and Ni-Co layered double hydroxides as the positive electrodes, in KOH electrolytes, are also demonstrated to show practicability. This work provides an opportunity to develop high-performance energy storage devices with the 2D nanomesh. • Ti 3 C 2 MXene nanomesh was constructed by chemical oxidation and etching. • The restacking issue was solved by the rich in-plane pores in MXene nanomesh. • Our design provides a promising way for high performance supercapacitors. [ABSTRACT FROM AUTHOR]