The chiral Majorana fermion is a massless self-conjugate fermion which can arise as the edge state of certain 2D topological matters. It has been theoretically predicted and experimentally observed ...in a hybrid device of a quantum anomalous Hall insulator and a conventional superconductor. Its closely related cousin, the Majorana zero mode in the bulk of the corresponding topological matter, is known to be applicable in topological quantum computations. Here we show that the propagation of chiral Majorana fermions leads to the same unitary transformation as that in the braiding of Majorana zero modes and propose a platform to perform quantum computation with chiral Majorana fermions. A Corbino ring junction of the hybrid device can use quantum coherent chiral Majorana fermions to implement the Hadamard gate and the phase gate, and the junction conductance yields a natural readout for the qubit state.
The performance of electrode material is correlated with the choice of electrolyte, however, how the solvation has significant impact on electrochemical behavior is underdeveloped. Herein, ...N‐heteropentacenequinone (TAPQ) is investigated to reveal the solvation effect on the performance of sodium‐ion batteries in different electrolyte environment. TAPQ cycled in diglyme‐based electrolyte exhibits superior electrochemical performance, but experiences a rapid capacity fading in carbonate‐based electrolyte. The function of solvation effect is mainly embodied in two aspects: one is the stabilization of anion intermediate via the compatibility of electrode and electrolyte, the other is the interfacial electrochemical characteristics influenced by solvation sheath structure. By revealing the failure mechanism, this work presents an avenue for better understanding electrochemical behavior and enhancing performance from the angle of solvation effect.
N‐heteropentacenequinone (TAPQ) is studied as electrode material to investigate the solvation effect in different sodium‐ion battery electrolytes. By revealing the failure mechanism of TAPQ in carbonate‐based electrolytes, we discuss how the solvation effect influences interfacial electrochemical characteristics and attributed the electrolyte compatibility to the stabilization effect of reaction intermediate via solvation effect.
Exploring high‐efficiency and stable halide perovskite‐based photocatalysts for the selective reduction of CO2 to methane is a challenge because of the intrinsic photo‐ and chemical instability of ...halide perovskites. In this study, halide perovskites (Cs3Bi2Br9 and Cs2AgBiBr6) were grown in situ in mesoporous TiO2 frameworks for an efficient CO2 reduction. Benchmarked CH4 production rates of 32.9 and 24.2 μmol g−1 h−1 with selectivities of 88.7 % and 84.2 %, were achieved, respectively, which are better than most reported halide perovskite photocatalysts. Focused ion‐beam sliced‐imaging techniques were used to directly image the hyperdispersed perovskite nanodots confined in mesopores with tunable sizes ranging from 3.8 to 9.9 nm. In situ X‐ray photoelectronic spectroscopy and Kelvin probe force microscopy showed that the built‐in electric field between the perovskite nanodots and mesoporous titania channels efficiently promoted photo‐induced charge transfer. Density functional theory calculations indicate that the high methane selectivity was attributed to the Bi‐adsorption‐mediated hydrogenation of *CO to *HCO that dominates CO desorption.
Halide perovskites (Cs3Bi2Br9, Cs2AgBiBr6) are grown in situ in a mesoporous titania framework for efficient CO2 reduction reaction (CO2RR). A benchmarked production rate of CH4 (32.9 and 24.2 μmol g−1 h−1) is achieved with selectivity values of 88.7 % and 84.2 %, respectively. In situ X‐ray photoelectronic spectroscopy and Kelvin probe force microscopy reveal that the inner surface built‐in electric field between the perovskite nanodots and mesoporous titania channels can efficiently promote photo‐induced charge transfer.
Organic materials have attracted much attention in aqueous zinc‐ion batteries (AZIBs) due to their sustainability and structure‐designable, but their further development is hindered by the high ...solubility, poor conductivity, and low utilization of active groups, resulting in poor cycling stability, terrible rate capability, and low capacity. In order to solve these three major obstacles, a novel organic host, benzobnaphtho2’,3’:5,61,4dithiino2,3‐ithianthrene‐5,7,9,14,16,18‐hexone (BNDTH), with abundant electroactive groups and stable extended π‐conjugated structure is synthesized and composited with reduced graphene oxide (RGO) through a solvent exchange composition method to act as the cathode material for AZIBs. The well‐designed BNDTH/RGO composite exhibits a high capacity of 296 mAh g−1 (nearly a full utilization of the active groups), superior rate capability of 120 mAh g−1, and a long lifetime of 58 000 cycles with a capacity retention of 65% at 10 A g−1. Such excellent performance can be attributed to the ingenious structural design of the active molecule, as well as the unique solvent exchange composition strategy that enables effective dispersion of excess charge on the active molecule during discharge/charge process. This work provides important insights for the rational design of organic cathode materials and has significant guidance for realizing ideal high performance in AZIBs.
A fully composited benzobnaphtho2',3':5,61,4dithiino2,3‐ithianthrene‐5,7,9,14,16,18‐hexone/reduced graphene oxide (BNDTH/RGO) is designed to simultaneously conquer the low utilization of active sites, intrinsic poor conductivity, and strong solubility of organic electrode materials, realizing the construction of Zn‐organic batteries with record‐high cycling stability. This work brings new opportunities for the exploration of ultra‐stable organic cathode materials for Zn‐ion batteries.
The slow reaction kinetics and structural instability of organic electrode materials limit the further performance improvement of aqueous zinc‐organic batteries. Herein, we have synthesized a ...Z‐folded hydroxyl polymer polytetrafluorohydroquinone (PTFHQ) with inert hydroxyl groups that could be partially oxidized to the active carbonyl groups through the in situ activation process and then undertake the storage/release of Zn2+. In the activated PTFHQ, the hydroxyl groups and S atoms enlarge the electronegativity region near the electrochemically active carbonyl groups, enhancing their electrochemical activity. Simultaneously, the residual hydroxyl groups could act as hydrophilic groups to enhance the electrolyte wettability while ensuring the stability of the polymer chain in the electrolyte. Also, the Z‐folded structure of PTFHQ plays an important role in reversible binding with Zn2+ and fast ion diffusion. All these benefits make the activated PTFHQ exhibit a high specific capacity of 215 mAh g−1 at 0.1 A g−1, over 3400 stable cycles with a capacity retention of 92 %, and an outstanding rate capability of 196 mAh g−1 at 20 A g−1.
A hydroxyl polymer PTFHQ has been designed to obtain electrochemical activity through an in situ electrochemical activation process. The synergistic effects of the different functional groups (C=O, −OH, and −S−) and the unique Z‐folded structure of the activated PTFHQ effectively improve its electrochemical activity and contribute to the rapid reaction kinetics, realizing the construction of high‐performance zinc‐organic batteries.
Organic electrode materials (OEMs) have gathered extensive attention for aqueous zinc‐ion batteries (AZIBs) due to their structural diversity and molecular designability. However, the reported ...research mainly focuses on the design of the planar configuration of OEMs and does not take into account the important influence of the spatial structure on the electrochemical properties, which seriously hamper the further performance liberation of OEMs. Herein, this work has designed a series of thioether‐linked naphthoquinone‐derived isomers with tunable spatial structures and applied them as the cathodes in AZIBs. The incomplete conjugated structure of the elaborately engineered isomers can guarantee the independence of the redox reaction of active groups, which contributes to the full utilization of active sites and high redox reversibility. In addition, the position isomerization of naphthoquinones on the benzene rings changes the zincophilic activity and redox kinetics of the isomers, signifying the importance of spatial structure on the electrochemical performance. As a result, the 2,2′‐(1,4‐phenylenedithio) bis(1,4‐naphthoquinone) (p‐PNQ) with the smallest steric hindrance and the most independent redox of active sites exhibits a high specific capacity (279 mAh g−1), an outstanding rate capability (167 mAh g−1 at 100 A g−1), and a long‐term cycling lifetime (over 2800 h at 0.05 A g−1).
The naphthoquinone derivative isomers with nonplanar and partially conjugated structures have been designed to guarantee high structure stability and redox unit independence, realizing the construction of Zn‐organic batteries with high achievable capacity, stable cycling performance, and ultrarapid rate capability.
Due to their potential applications in physiological monitoring, diagnosis, human prosthetics, haptic perception, and human–machine interaction, flexible tactile sensors have attracted wide research ...interest in recent years. Thanks to the advances in material engineering, high performance flexible tactile sensors have been obtained. Among the representative pressure sensing materials, 2D layered nanomaterials have many properties that are superior to those of bulk nanomaterials and are more suitable for high performance flexible sensors. As a class of 2D inorganic compounds in materials science, MXene has excellent electrical, mechanical, and biological compatibility. MXene‐based composites have proven to be promising candidates for flexible tactile sensors due to their excellent stretchability and metallic conductivity. Therefore, great efforts have been devoted to the development of MXene‐based composites for flexible sensor applications. In this paper, the controllable preparation and characterization of MXene are introduced. Then, the recent progresses on fabrication strategies, operating mechanisms, and device performance of MXene composite‐based flexible tactile sensors, including flexible piezoresistive sensors, capacitive sensors, piezoelectric sensors, triboelectric sensors are reviewed. After that, the applications of MXene material‐based flexible electronics in human motion monitoring, healthcare, prosthetics, and artificial intelligence are discussed. Finally, the challenges and perspectives for MXene‐based tactile sensors are summarized.
The latest research advances in preparation strategies and characterization of MXene‐based tactile sensors are comprehensively introduced and discussed. Meanwhile, their applications in human motion monitoring, healthcare, prosthetics, and artificial intelligence are reviewed.
Abstract
The emergence of atomically thin van der Waals magnets provides a new platform for the studies of two-dimensional magnetism and its applications. However, the widely used measurement methods ...in recent studies cannot provide quantitative information of the magnetization nor achieve nanoscale spatial resolution. These capabilities are essential to explore the rich properties of magnetic domains and spin textures. Here, we employ cryogenic scanning magnetometry using a single-electron spin of a nitrogen-vacancy center in a diamond probe to unambiguously prove the existence of magnetic domains and study their dynamics in atomically thin CrBr
3
. By controlling the magnetic domain evolution as a function of magnetic field, we find that the pinning effect is a dominant coercivity mechanism and determine the magnetization of a CrBr
3
bilayer to be about 26 Bohr magnetons per square nanometer. The high spatial resolution of this technique enables imaging of magnetic domains and allows to locate the sites of defects that pin the domain walls and nucleate the reverse domains. Our work highlights scanning nitrogen-vacancy center magnetometry as a quantitative probe to explore nanoscale features in two-dimensional magnets.
Covalent organic frameworks (COFs) are an emerging class of functional nanostructures with intriguing properties, due to their unprecedented combination of high crystallinity, tunable pore size, ...large surface area, and unique molecular architecture. The range of properties characterized in COFs has rapidly expanded to include those of interest for numerous applications ranging from energy to environment. Here, a background overview is provided, consisting of a brief introduction of porous materials and the design feature of COFs. Then, recent advancements of COFs as a designer platform for a plethora of applications are emphasized together with discussions about the strategies and principles involved. Finally, challenges remaining for this type material for real applications are outlined.
Covalent organic frameworks (COFs) are porous crystalline polymers with tunable composition and structural architecture, enabling precise control over functionality, density, and spatial arrangement. This universal control makes them a particularly promising platform for task‐led design. Recent advancements of COFs for numerous applications are reviewed and the challenges and opportunities associated with processing and large‐scale synthesis are discussed.
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