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Prussian blue analogs (PBAs) featuring with 3D open framework are recognized as promising cathode candidates for Zinc‐ion batteries (ZIBs). However, challenges such as unsatisfactory active site utilization, low conductivity, and abundant structural vacancies have impeded fulfillment of their potential. In this work, a conductive in‐plane porous MXene is for the first time adopted as a multifunctional host material to enhance cobalt hexacyanoferrate (CoHCF) growth and crystallinity. Particularly, the uniform surface charges on MXene are identified to induce anisotropic and highly crystalline CoHCF, which are critical to alleviating the practical drawbacks associated with the PBAs family. Empowered by the targeted modification, the CoHCF nanotube/MXene composite realizes high surface area and low defectiveness, resulting in an impressive capacity of 197 mAh g−1 at 0.1 A g−1 and capacity retention of 95.3% over 3000 cycles at 2.0 A g−1. X‐ray spectroscopy and density functional theory (DFT) reveal that Co─C bonds in the heterostructure facilitate rapid electron/Zn‐ion transfer, enhancing Zn storage kinetics. To validate practical applicability, pouch cells incorporating Zn|CoHCF/MXene are further examined. This composition strategy, utilizing MXene as a multifunctional template, enhances the surface area, conductivity, and crystallinity of PBAs as cathodes for ZIBs, showcasing the significant potential for large‐scale energy storage applications. [ABSTRACT FROM AUTHOR]

Continuous discoveries in the field of metallic conductive MXenes have shown their feasibility as electrode materials, but their employment remains impeded by low surface area and inhomogeneous edge terminations generated by hazardous HF etching. To solve these problems, for the first time, a eutectic mixture etching strategy is utilized to accomplish one‐step synthesis of Cl‐terminated MXene (Ti3C2Cl2) with tunable in‐plane porosity from a MAX precursor (Ti3AlC2) through manipulating the phase transition of the selected salt melt. Specifically, the temperature and composition of the NaCl/ZnCl2 salt mixture are controlled to initiate a mechanism that creates and critically preserves the MXene pore structure, leading to substantial increment in material mesoporosity and a fourfold increase in surface area. Moreover, X‐ray spectroscopy analyses reveal increased TiC6 octahedral symmetry and density functional theory (DFT) modeling suggests a lower Li diffusion barrier, which imply high suitability for ion transport. Benefiting from these optimizations, mesoporous Ti3C2Cl2 delivers a high capacity of 382 mAh g−1 at 0.1 A g−1 as a dual‐ion battery anode, with capacity retention over 89% after 1000 cycles at 2.0 A g−1. Overall, this study presents a green chemistry approach that enables direct synthesis of MXenes with optimal porosity and surface termination for electrochemical applications, providing fresh insights for targeted structure modifications. [ABSTRACT FROM AUTHOR]

Nowadays, evolutions in wireless telecommunication industries, such as the emergence of complex 5G technology, occur together with massive development in portable electronics and wireless systems. This positive progress has come at the expense of significant electromagnetic interference (EMI) pollution, which requires the development of highly efficient shielding materials with low EM reflection. The manipulation of MXene surface functional groups and, subsequently, incorporation into engineered polymer matrices provide mechanisms to improve the electromechanical performance of conductive polymer composites (CPCs) and create a safe EM environment. Herein, Ti 3 C 2 T x MXene nanoflakes were first synthesized and then, taking advantage of their abundant surface functional groups, polyaniline (PA) nanofibers were grafted onto the MXene surface via oxidant-free oxidative polymerization at two different MXene to monomer ratios. The electrical conductivity, EMI shielding effectiveness (SE), and mechanical properties of poly (vinylidene fluoride) (PVDF)-based CPCs at different nanomaterial loadings were then thoroughly investigated. A very low percolation threshold of 1.8 vol % and outstanding electrical conductivities of 0.23, 0.195, and 0.17 S/cm were obtained at 6.9 vol % loading for PVDF-MXene, PVDF-MX 2 AN 1 , and PVDF-MX 1 AN 1 , respectively. Compared to the pristine MXene composite, surface modification significantly enhanced the EMI SE of the PVDF-MX 2 AN 1 and PVDF-MX 1 AN 1 composites by 19.6 and 32.7%, respectively. The remarkable EMI SE enhancement of the modified nanoflakes was attributed to (i) the intercalation of PA nanofibers between MXene layers, resulting in better nanoflake exfoliation, (ii) a large amount of dipole and interfacial polarization dissipation by constructing capacitor-like structures between nanoflakes and polymer chains, and (iii) augmented EMI attenuation via conducting PA nanofibers. The surface modification of the MXene nanoflakes also enhanced the interfacial interactions between PVDF chains and nanoflakes, which resulted in an improved Young's modulus of the PVDF matrix by about 67 and 46% at 6.9 vol % loading for PVDF-MX 2 AN 1 and PVDF-MX 1 AN 1 composites, respectively.