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According to the United Nations, around 53 million metric tons of electronic waste is produced every year, worldwide, the big majority of which goes unprocessed. With the rapid advances in AI technologies and adoption of smart gadgets, the demand for powerful logic and memory chips is expected to boom. Therefore, the development of green electronics is crucial to minimizing the impact of the alarmingly increasing e‐waste. Here, it is shown the application of a green synthesized, chemically stable, carbonyl‐decorated 2D organic, and biocompatible polymer as an active layer in a memristor device, sandwiched between potentially fully recyclable electrodes. The 2D polymer's ultramicro channels, decorated with C═O and O─H groups, efficiently promote the formation of copper nanofilaments. As a result, the device shows excellent bipolar resistive switching behavior with the potential to mimic synaptic plasticity. A large resistive switching window (103), low SET/RESET voltage of ≈0.5/−1.5 V), excellent device‐to‐device stability and synaptic features are demonstrated. Leveraging the device's synaptic characteristics, its applications in image denoising and edge detection is examined. The results show a reduction in power consumption by a factor of 103 compared to a traditional Tesla P40 graphics processing unit, indicating great promise for future sustainable AI‐based applications. [ABSTRACT FROM AUTHOR]

Cobalt is considered an essential element for layered cathode active materials supporting enhanced lithium‐ion conductivity and structural stability. Herein, we investigated the influence of Co concentration on the physicochemical properties and electrochemical performance of lithium‐rich layered oxides (LRLOs) with different Co content (Li1.2Ni0.2‐x/2Mn0.6‐x/2CoxO2, x=0, 0.04, and 0.08). Though the presence of Co grants structural stability to LRLOs, superior long‐term cycling stability is achieved with the Co‐free LRLO retaining 88.1 % of the initial specific capacity (vs. 75.9 % of Li1.2Ni0.16Mn0.56Co0.08O2) after 300 galvanostatic cycles at 250 mA g−1 (1 C). The chemical stability on the surface of LRLOs containing Co declines faster, indicating a higher bulk structural stability not being the primary determinant of the LRLOs' cycling performance. Ex‐situ investigations indicate that the superior cycling stability of Co‐free LRLO is obtained by reducing the Mn‐related redox at discharge, which contributes to the large degree of polarization and low energy efficiency. Finally, the full‐cell configured with the optimized LRLO as cathode and graphite anode delivers an energy density of 464 Wh kg−1 at C/10, and 74.4 % and 94.3 % of retention in discharge specific capacity and average voltage at the 1000th cycle, demonstrating the applicability of Co‐free LRLO for sustainable LIBs. [ABSTRACT FROM AUTHOR]

Zeolites hold importance as catalysts and membranes across numerous industrial processes that produce most of the world's fuels and chemicals. In zeolite catalysis, the rate of molecular diffusion inside the micropore channels defines the catalyst's longevity and selectivity, thereby influencing the catalytic efficiency. Decreasing the diffusion pathlengths of zeolites to the nanoscopic level by fabricating well‐organized hierarchically porous architecture can efficiently overcome their intrinsic mass‐transfer limitations without losing hydrothermal stability. We report a rational post‐synthetic design for synthesizing hierarchically ordered FAU‐type zeolites exhibiting 2D‐hexagonal (P6mm) and 3D‐cubic (Ia3‾ ${\bar{3}}$ d) mesopore channels. The synthesis involves methodical incision of the parent zeolite into unit‐cell level zeolitic fragments by in situ generated base and bulky surfactants. The micellar ensembles formed by these surfactant‐zeolite interactions are subsequently reorganized into various ordered mesophases by tuning the micellar curvature with ion‐specific interactions (Hofmeister effect). Unlike conventional crystallization, which offers poor control over mesophase formation due to kinetic constraints, crystalline mesostructures can be developed under dilute, mild alkaline conditions by controlled reassembly. The prepared zeolites with nanometric diffusion pathlengths have demonstrated excellent yields of naphtha and middle‐distillates in vacuum gas oil hydrocracking with decreased coke deposition. [ABSTRACT FROM AUTHOR]

In recent years, all‐solid‐state batteries (ASSBs) with metal anodes have witnessed significant developments due to their high energy and power density as well as their excellent safety record. While intergranular dendritic lithium growth in inorganic solid electrolytes (SEs) has been extensively studied for lithium ASSBs, comparable knowledge is missing for sodium‐based ASSBs. Therefore, polycrystalline Na‐β″‐alumina is employed as a SE model material to investigate the microstructural influence on sodium filament growth during deposition of sodium metal at the anode. The research focuses on the relationship between the microstructure, in particular grain boundary (GB) type and orientation, sodium filament growth, and sodium ion transport, utilizing in situ transmission electron microscopy (TEM) measurements in combination with crystal orientation analysis. The effect of the anisotropic sodium ion transport at/across GBs depending on the orientation of the sodium ion transport planes and the applied electric field on the current distribution and the position of sodium filament growth is explored. The in situ TEM analysis is validated by large field of view post‐mortem secondary ion mass spectrometer (SIMS) analysis, in which sodium filament growth within voids and along grain boundaries is observed, contributing to the sodium network formation potentially leading to failure of batteries. [ABSTRACT FROM AUTHOR]

The development of commercially viable fuel cells and metal‐air batteries requires effective and cheap bifunctional catalysts for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). Multi‐component Pt−Fe−Co−Ni nanoparticles on multi‐walled carbon nanotubes (MWCNTs) were synthesized by wet chemistry route via NaBH4 reduction of metal salts, followed by sintering at different temperatures. The catalyst demonstrates an excellent ORR activity and a promising OER activity in 0.1 m KOH, with a bi‐functional over‐potential, ΔE of 0.83 V, which is comparable to the values of Pt/C or RuO2. Furthermore, it shows outstanding long‐term stability in ORR and OER, namely diffusion limited current density at a potential of 0.3 V decreased just by 5.5 % after 10000 cycles in ORR. The results of the PFCN@NT300 indicate a significant effect of the substitution of Pt by the transition metal (TM) and the formation of nanoparticles on the catalytic performance, especially in the OER. [ABSTRACT FROM AUTHOR]

Sodium‐ion and potassium‐ion batteries (NIBs and KIBs) are considered promising alternatives to replace lithium‐ion batteries (LIBs) in energy storage applications due to the natural abundance and low cost of Na and K. Nevertheless, a critical challenge is that the large size of Na+/K+ leads to a huge volume change of the hosting material during electrochemical cycling, resulting in rapid capacity decay. Among negative candidates for alkali‐metal‐ion batteries, SnS2 is attractive due to the competitively high specific capacity, low redox potential and high abundance. Porous few‐layer SnS2 nanosheets are in situ grown on reduced graphene oxide, forming a SnS2‐rGO sandwich structure via strong C−O−Sn bonds. This nano‐scaled sandwich structure not only shortens Na+/K+ and electron transport pathways but also accommodates volume expansion, thereby enabling high and stable electrochemical cycling performance of SnS2‐rGO. This work explores the influence of different conductive carbons (Super P and C65) on the SnS2‐rGO electrode. In addition, the effects of the electrolyte additive fluoroethylene carbonate (FEC) on the electrochemical performance in NIBs and KIBs is evaluated. This work provides guidelines for optimized electrode structure design, electrolyte additives and carbon additives for the realization of better NIBs and KIBs. [ABSTRACT FROM AUTHOR]

Upon cycling, Li‐rich Mn‐based disordered rocksalt (DRS) oxyfluoride cathode materials undergo unwanted degradation processes, which are triggered by chemical side reactions or irreversible oxygen redox activity, especially at high voltages and in contact with the electrolyte. A surface coating can be an effective strategy to mitigate these parasitic reactions. However, oxyfluorides generally experience limited stability, which makes the application of coatings requiring high temperatures challenging. For this purpose, this study is dealing with the implementation of a chemically inert and Li ion conducting borate‐based coating at mild‐temperature (300 °C), following a dry process on the Li2Mn2/3Ti1/3O2F particles. Electrochemical characterization, as function of the amount of coating, C‐rate and temperature, indicate that the coated samples possess considerably improved capacity retention and reduced Mn‐dissolution, however, at the cost of a measurable initial capacity loss. The authors further demonstrate that the presence of the coating reduces the interfacial resistance, which is beneficial for Li ion transfer. The 3 wt%‐coated sample loses only 27% of the capacity, where around 130 mAh g−1 after 100 cycles is retained. The utilization of surface modification can open up a path for further development of DRS cathode materials with high performance for Li‐ion batteries. [ABSTRACT FROM AUTHOR]

LiNi0.5Mn1.5O4 (LNMO) is a promising cathode in lithium‐ion batteries (LIBs) due to its high operating voltage and open Li+ diffusion framework. However, the instability of the electrode–electrolyte interface and the negative environmental impact of electrode fabrication processes limit its practical application. Therefore, switching electrode processing conditions to aqueous and understanding the accompanying surface structural evolution are imperative. Here, water‐treated, poly(acrylic acid) (PAA)‐treated, and H3PO4‐treated LNMO, labeled as W‐LNMO, A‐LNMO, and H‐LNMO, are studied systematically. W‐LNMO shows a high concentration of Mn3+ induced by Li loss while a conformal PAA layer formed on A‐LNMO reduces this phenomenon. H‐LNMO displays a second MnPO4∙H2O phase. Upon cycling, a fast capacity decay is observed in W‐LNMO while an extra plateau at ≈2.7 V appears in the initial charging, corresponding to a two‐phase transition. A surface reconstruction layer from a spinel to a rock‐salt phase with a reductive Mn2+ segregation is observed in W‐LNMO after 105 cycles. The PAA layer persists on A‐LNMO and alleviates the capacity decay. H‐LNMO delivers a relatively low capacity due to the formation of a MnPO4∙H2O phase. This study provides new insights into manipulating the surface chemistry of LNMO cathodes to enable aqueous, large‐scale processingin LIBs. [ABSTRACT FROM AUTHOR]

Hierarchical zeolites are regarded as promising catalysts due to their well‐developed porosity, increased accessible surface area, and minimal diffusion constraints. Thus far, the focus has been on the creation of mesopores in zeolites, however, little is known about a microporosity upgrading and its effect on the diffusion and catalytic performance. Here the authors show that the "birth" of mesopore formation in faujasite (FAU) type zeolite starts by removing framework T atoms from the sodalite (SOD) cages followed by propagation throughout the crystals. This is evidenced by following the diffusion of xenon (Xe) in the mesoporous FAU zeolite prepared by unbiased leaching with NH4F in comparison to the pristine FAU zeolite. A new diffusion pathway for the Xe in the mesoporous zeolite is proposed. Xenon first penetrates through the opened SOD cages and then diffuses to supercages of the mesoporous zeolite. Density functional theory (DFT) calculations indicate that Xe diffusion between SOD cage and supercage occurs only in hierarchical FAU structure with defect‐contained six‐member‐ring separating these two types of cages. The catalytic performance of the mesoporous FAU zeolite further indicates that the upgraded microporosity facilitates the intracrystalline molecular traffic and increases the catalytic performance. [ABSTRACT FROM AUTHOR]

Abstract: Here the thermal behaviour and the surface reactivity of cobalt catalysts supported by alumina‐silica and promoted by platinum were investigated by in situ transmission electron microscopy (in situ TEM) in a syngas environment. At the standard operating temperature of 220 °C, atomic diffusion and sintering processes onto the support are quite limited on the time scale of the TEM experiment. At temperatures between 350 and 450 °C, particles encapsulation occurred due to a higher CO dissociation and conversion into graphitic layers. Beyond 500 °C, carbon nanotubes (CNTs) growth is activated and the particles undergo (i) morphological changes through continuous elongation and contraction; and (ii) microstructural changes with the appearance of cobalt carbide. By comparing reactions under pure CO and a mixture CO−H2, it was shown that the addition of dihydrogen to CO increased the rate of CNTs growth and modified the structure of the nanotubes. These results clearly demonstrate the strong ability of the in situ TEM to provide the main lines of the reactivity synopsis of nanocatalysts at a nanometric scale under temperature and reactive gas. [ABSTRACT FROM AUTHOR]

The C66(COOH)12 hexa-adduct has been successfully used as a building block to construct carboxylate bridged 3D networks with very homogeneous sub-1.8 nm ruthenium nanoparticles. The obtained nanostructures are active in nitrobenzene selective hydrogenation. [ABSTRACT FROM AUTHOR]

Zeolites are widely used in many commercial processes, mostly as catalysts or adsorbents. Understanding their intimate structure at the nanoscale is the key to control their properties and design the best materials for their ever increasing uses. Herein, we report a new and controllable fluoride treatment for the non-discriminate extraction of zeolite framework cations. This sheds new light on the sub-structure of commercially relevant zeolite crystals: they are segmented along defect zones exposing numerous nanometer-sized crystalline domains, separated by low-angle boundaries, in what were apparent single-crystals. The concentration, morphology, and distribution of such domains analyzed by electron tomography indicate that this is a common phenomenon in zeolites, independent of their structure and chemical composition. This is a milestone to better understand their growth mechanism and rationally design superior catalysts and adsorbents. [ABSTRACT FROM AUTHOR]

The principle aspects and constraints of the dynamics and kinetics of zeolite nucleation in hydrogel systems are analyzed on the basis of a model Na-rich aluminosilicate system. A detailed time-series EMT-type zeolite crystallization study in the model hydrogel system was performed to elucidate the topological and temporal aspects of zeolite nucleation. A comprehensive set of analytical tools and methods was employed to analyze the gel evolution and complement the primary methods of transmission electron microscopy (TEM) and nuclear magnetic resonance (NMR) spectroscopy. TEM tomography reveals that the initial gel particles exhibit a core-shell structure. Zeolite nucleation is topologically limited to this shell structure and the kinetics of nucleation is controlled by the shell integrity. The induction period extends to the moment when the shell is consumed and the bulk solution can react with the core of the gel particles. These new findings, in particular the importance of the gel particle shell in zeolite nucleation, can be used to control the growth process and properties of zeolites formed in hydrogels. [ABSTRACT FROM AUTHOR]

The technological exploitation of the extraordinary properties of graphene relies on the ability to achieve full control over the production of a high-quality material and its processing by up-scalable approaches in order to fabricate large-area films with single-layer or a few atomic-layer thickness, which might be integrated in working devices. A simple method is reported for producing homogenous dispersions of unfunctionalized and non-oxidized graphene nanosheets in Nmethyl- 2-pyrrolidone (NMP) by using simple molecular modules, which act as dispersion-stabilizing compounds during the liquid-phase exfoliation (LPE) process, leading to an increase in the concentration of graphene in dispersions. The LPE-processed graphene dispersion was shown to be a conductive ink. This approach opens up new avenues for the technological applications of this graphene ink as low-cost electrodes and conducting nanocomposite for electronics. [ABSTRACT FROM AUTHOR]

A correction to the article "3D Study of the Morphology and Dynamics of Zeolite Nucleation" that was published in a 2015 is presented.