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Aluminum (Al)‐ion batteries have emerged as a potential alternative to conventional ion batteries that rely on less abundant and costly materials like lithium. Nonetheless, given the nascent stage of advancement in Al‐ion batteries (AIBs), attaining electrode materials that can leverage both intercalation capacity and structural stability remains challenging. Herein, we demonstrate a C3N4‐derived layered N,S heteroatom−doped carbon, obtained at different pyrolysis temperatures, as a cathode material for AIBs, encompassing the diffusion−controlled intercalation and surface‐induced capacity with ultrahigh reversibility. The developed layered N,S‐doped corbon (N,S‐C) cathode, synthesized at 900 °C, delivers a specific capacity of 330 mAh g−1 with a relatively high coulombic efficiency of ~85% after 500 cycles under a current density of 0.5 A g−1. Owing to its reinforced adsorption capability and enlarged interlayer spacing by doping N and S heteroatoms, the N,S‐C900 cathode demonstrates outstanding energy storage capacity with excellent rate performance (61 mAh g−1 at 20 A g−1) and ultrahigh reversibility (90 mAh g−1 at 5 A g−1 after 10 000 cycles). [ABSTRACT FROM AUTHOR]

Halide perovskite colloidal nanocrystals (NCs) have enabled considerable progress in light conversion applications. However, the presence of unavoidable defect states and phase transition effects can accelerate undesirable rapid charge recombination of the photogenerated charge carriers. To address this issue, chromophores with an anchoring moiety are often used to modify the surface of the NCs, promoting prolonged charge separation through electron or energy transfer processes for optoelectronic applications. Here, steady‐state and time‐resolved spectroscopy methods are combined with density functional theory (DFT) calculations to explore and decipher the excited‐state interaction in colloidal CsPbX3 (X = Br, I) NCs with a rhodamine 6G (Rh6G) hybrid assembly. The results show that Rh6G dimerizes even at low concentrations, as evidenced by DFT calculations. The binding of Rh6G on the NC surface is confirmed by FTIR and NMR spectroscopy techniques. In addition, transient absorption spectroscopy reveals directional sub‐ps electron transfer from Rh6G to CsPbI3 NCs, whereas energy transfer occurs from CsPbBr3 to Rh6G, which ultimately recombines in the µs time regime. The findings highlight the simplest and most practical approaches for studying and tailoring the excited‐state interaction in colloidal perovskite NCs and chromophore assembly. [ABSTRACT FROM AUTHOR]

Aqueous zinc (Zn) ion batteries (AZIBs) are regarded as one of the promising candidates for next‐generation electrochemical energy storage systems due to their low cost, high safety, and environmental friendliness. However, the commercialization of AZIBs has been severely restricted by the growth of dendrite at the Zn metal anode. Tailoring the planar‐structured Zn anodes into three‐dimensional (3D) structures has proven to be an effective way to modulate the plating/stripping behavior of Zn anodes, resulting in the suppression of dendrite formation. This review provides an up‐to‐date review of 3D structured Zn metal anodes, including working principles, design, current status, and future prospects. We aim to give the readers a comprehensive understanding of 3D‐structured Zn anodes and their effective usage to enhance AZIB performance. [ABSTRACT FROM AUTHOR]

Low ionic migration and compromised interfacial stability pose challenges for low‐temperature batteries. In this work, we discovered that even with the state‐of‐the‐art localized high‐concentration electrolytes (LHCEs), uncontrolled Na electrodeposition occurs with a huge overpotential of >1.2 V at −20 °C, leading to cell failure within tens of hours. To address this, we introduce a new electrolyte category that incorporates an ionic liquid as a key solvation species. Diverging from traditional LHCEs, the IL‐tailored LHCE facilitates an anion–solvent‐molecules exchange within the solvation sheath between Na+ and organic cations at low temperatures. This behavior reduces solvation cluster size and strengthens Na+–anion coordination, which proves instrumental in enabling fast ionic dynamics in both the bulk liquid and at the interface. Therefore, durable Na electrodeposition and shuttle‐free, 0.5 Ah sodium–sulfur pouch cells are achieved at −20 °C, for the first time, surpassing the limitations of typical LHCEs. This tailoring strategy opens a  new design direction for advanced batteries operating in fast‐charge and wide‐temperature scenarios. [ABSTRACT FROM AUTHOR]

The ever‐increasing prevalence of intelligent electronics underscores an escalating demand for sustainable power sources. Among the emerging energy harvesting technologies, triboelectric nanogenerators (TENGs) stand out as a promising solution for such pressing needs. To date, ongoing efforts have primarily focused on enhancing TENG output, particularly through the development of novel triboelectric materials. Among the potential candidates is the thriving class of two‐dimensional transition‐metal carbides, MXenes, which have predominantly been incorporated into triboelectric layers as nanofillers to enhance their triboelectric properties. Yet, the specific triboelectric characteristics of distinct MXenes remain marginally explored. Herein, the triboelectric properties of various metal carbide MXenes, i.e., V2CTx, Ti3C2Tx, and Nb2CTx, are investigated by assessing the performance of various MXene‐based TENGs combined with different polymers and analyzing their surface potential. According to the attained triboelectric polarities, a triboelectric series of the studied MXenes is determined, demonstrating their remarkable positive triboelectric properties. Further investigations preliminarily reveal the influence of the synthesis method, etchants, intercalating compounds, and postsynthesis procedures on the triboelectric properties of MXenes. Hence, beyond extending the conventional triboelectric series to different metal carbide MXenes, the findings present innovative perspectives on leveraging MXenes to develop high‐performance TENGs for flexible and wearable electronics. [ABSTRACT FROM AUTHOR]

We report the engineering and synthesis of peptide nucleic acid-functionalized Ti 3 C 2 T x MXene nanosheets as a novel transducing material for amplification-free, nanoparticle-free, and isothermal electrochemical detection of microRNA biomarkers. Through bio-orthogonal copper-free click chemistry, azido-modified MXene nanosheets are covalently functionalized with clickable peptide nucleic acid probes targeting prostate cancer biomarker hsa-miR-141. The platform demonstrates a wide dynamic range, single-nucleotide specificity, and 40 aM detection limit outperforming more complex, amplification-based methods. Its versatility, analytical performance, and stability under serum exposure highlight the immense potential of this first example of click-conjugated MXene in the next generation of amplification-free biosensors.

Solution-processable poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is an important polymeric conductor used extensively in organic flexible, wearable, and stretchable optoelectronics. However, further enhancing its conductivity and long-term stability while maintaining its superb mechanical properties remains challenging. Here, a novel post-treatment approach to enhance the electrical properties and stability of sub-20-nm-thin PEDOT:PSS films processed from solution is introduced. The approach involves a sequential post-treatment with HNO 3 and CsCl, resulting in a remarkable enhancement of the electrical conductivity of PEDOT:PSS films to over 5500 S cm -1 , along with improved carrier mobility. The post-treated films exhibit remarkable air stability, retaining over 85% of their initial conductivity even after 270 days of storage. Various characterization techniques, including X-ray photoelectron spectroscopy, atomic force microscopy, Raman spectroscopy, Hall effect measurements, and grazing incidence wide angle X-ray scattering, coupled with density functional theory calculations, provide insights into the structural changes and interactions responsible for these improvements. To demonstrate the potential for practical applications, the ultrathin PEDOT:PSS films are connected to an inorganic light-emitting diode with a battery, showcasing their suitability as transparent electrodes. This work presents a promising approach for enhancing the electrical conductivity of PEDOT:PSS while offering a comprehensive understanding of the underlying mechanisms that can guide further advances., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Aqueous ammonium ion batteries have garnered significant research interest due to their safety and sustainability advantages. However, the development of reliable ammonium-based full batteries with consistent electrochemical performance, particularly in terms of cycling stability, remains challenging. A primary issue stems from the lack of suitable anode materials, as the relatively large NH 4 + ions can cause structural damage and material dissolution during battery operation. To address this challenge, an Aza-based covalent organic framework (COF) material is introduced as an anode for aqueous ammonium ion batteries. This material exhibits superior ammonium storage capabilities compared to existing anode materials. It operates effectively within a negative potential range of 0.3 to‒1.0 V versus SCE, achieves high capacity even at elevated current densities (≈74 mAh g -1 at 10 A g -1 ), and demonstrates exceptional stability, retaining a capacity over 20 000 cycles at 1.0 A g -1 . Furthermore, by pairing this COF anode with a Prussian blue cathode, an ammonium rocking-chair full battery is developedd that maintains 89% capacity over 20 000 cycles at 1.0 A g -1 , surpassing all previously reported ammonium ion full batteries. This study offers insights for the design of future anodes for ammonium ion batteries and holds promise for high-energy storage solutions., (© 2024 Wiley‐VCH GmbH.)

Covalent organic frameworks (COFs) are viewed as promising organic electrode materials for metal-ion batteries due to their structural diversity and tailoring capabilities. In this work, firstly using the monomers N,N,N',N'-tetrakis(4-aminophenyl)-1,4-phenylenediamine (TPDA) and terephthaldehyde (TA), p-type phenylenediamine-based imine-linked TPDA-TA-COF is synthesized. To construct a bipolar redox-active, porous and highly crystalline polyimide-linked COF, i.e., TPDA-NDI-COF, n-type 1,4,5,8-naphthalene tetracarboxylic dianhydride (NDA) molecules are incorporated into p-type TPDA-TA-COF structure via postsynthetic linker exchange method. This tailored COF demonstrated a wide potential window (1.03.6 V vs Na + /Na) with dual redox-active centers, positioning it as a favorable cathode material for sodium-ion batteries (SIBs). Owing to the inheritance of multiple redox functionalities, TPDA-NDI-COF can deliver a specific capacity of 67 mAh g -1 at 0.05 A g -1 , which is double the capacity of TPDA-TA-COF (28 mAh g -1 ). The incorporation of carbon nanotube (CNT) into the TPDA-NDI-COF matrix resulted in an enhancement of specific capacity to 120 mAh g -1 at 0.02 A g -1 . TPDA-NDI-50%CNT demonstrated robust cyclic stability and retained a capacity of 92 mAh g -1 even after 10 000 cycles at 1.0 A g -1 . Furthermore, the COF cathode exhibited an average discharge voltage of 2.1 V, surpassing the performance of most reported COF as a host material., (© 2024 Wiley‐VCH GmbH.)

Wafer-scale transfer processes of 2D materials significantly expand their application space in scalable microelectronic devices with excellent and tunable properties through van der Waals (vdW) stacking. Unlike many 2D materials, wafer-scale transfer of MXene films for vdW contact engineering has not yet been reported. With their rich surface chemistry and tunable properties, the transfer of MXenes can enable enormous possibilities in electronic devices using interface engineering. Taking advantage of the MXene hydrophilic surface, a straightforward, green, and fast process for the transfer of MXene films at the wafer scale (4-inch) is developed. Uniform vdW stacking of several types of large-area heterojunctions including MXene/MXene (Ti 3 C 2 T x , Nb 2 CT x, and V 2 CT x ), MXene/MoS 2 , and MXene/Au is further demonstrated. Multilayer support is applied to minimize damage or deformation in the transfer process of patterned Ti 3 C 2 T x film. It allows us to fabricate thin film transistors and manipulate the MXene/MoS 2 interface through the intercalation of various 2D liquids. Particularly noteworthy is the significant enhancement of the interfacial carrier transfer efficiency by ≈2 orders of magnitude using hydrogen iodide (HI) intercalation. This finding indicates a wide range of possibilities for interface engineering by transferring MXene films and employing liquid-assisted interfacial intercalation., (© 2024 Wiley‐VCH GmbH.)

In advanced batteries, interphases serve as the key component in stabilizing the electrolyte with reactive electrode materials far beyond thermodynamic equilibria. While an active interphase facilitates the transport of working ions, an inactive interphase obstructs ion flow, constituting the primary barrier to the realization of battery chemistries. Here, a successful transformation of a traditionally inactive passivating layer on Mg-metal anode, characteristic of Mg-metal batteries with typical carbonate electrolytes, into an active and robust interphase in the Li-metal scenario is presented. By further strategically designing magnesiated Li + electrolytes, the in situ development of this resilient interphase on Li-metal anodes, imparting enduring stability to Li-metal batteries with nickel-rich cathodes is induced. It is identified that the strong affinity between Mg 2+ and anions in magnesiated Li + electrolytes assembles ionic clusters with a bias for reducibility, thereby catalyzing the creation of anion-derived interphases rich in inorganic constituents. The prevalence of ionic clusters induced by magnesiation of electrolytes has brought properties only available in high-concentration electrolytes, suggesting a fresh paradigm of tailing electrolytes for highly reversible LMBs., (© 2024 Wiley‐VCH GmbH.)

Superconductivty has recently been induced in MXenes through surface modification. However, the previous reports have mostly been based on powders or cold-pressed pellets, with no known reports on the intrinsic superconsucting properties of MXenes at the nanoale. Here, it is developed a high-temperature atomic exchange process in NH 3 atmosphere which induces superconductivity in either singleflakes or thin films of Nb 2 CT x MXene. The exchange process between nitrogen atoms and fluorine, carbon, and oxygen atoms in the MXene lattice and related structural adjustments are studied using both experiments and density functional theory. Using either single-flake or thin-film devices, an anisotropic magnetic response of the 2D superconducting transformation has been successfully revealed. The anisotropic superconductivity is further demonstrated using superconducting thin films uniformly deposited over a 4 in. wafers, which opens up the possibility of scalable MXene-based superconducting devices., (© 2023 Wiley-VCH GmbH.)