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Fine‐tuning the interfacial sites within heterogeneous catalysts is pivotal for unravelling the intricate structure–property relationship and optimizing their catalytic performance. Herein, a simple and versatile mixed‐dimensional assembly approach is proposed to create nanocrystal‐on‐nanowire superstructures with precisely adjustable numbers of biphasic interfaces. This method leverages an efficient self‐assembly process in which colloidal nanocrystals spontaneously organize onto Ag nanowires, driven by the solvophobic effect. Importantly, varying the ratio of the two components during assembly allows for accurate control over both the quantity and contact perimeter of biphasic interfaces. As a proof‐of‐concept demonstration, a series of Au‐on‐Ag superstructures with varying numbers of Au/Ag interfaces are constructed and employed as electrocatalysts for electrochemical CO2‐to‐CO conversion. Experimental results reveal a logarithmic linear relationship between catalytic activity and the number of Au/Ag interfaces per unit mass of Au‐on‐Ag superstructures. This work presents a straightforward approach for precise interface engineering, paving the way for systematic exploration of interface‐dependent catalytic behaviors in heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

To address the inherent limitations of conventional carbon nanotubes (CNTs), such as their tendency to agglomerate and scarcity of catalytic sites, the development of branched carbon nanotubes (BCNTs) with a unique hierarchical structure has emerged as a promising solution. Herein, gram scale quantities of densely branched and structurally consistent Ni−Fe decorated branched CNTs (Ni−Fe@BCNT) have been prepared. This uniform and densely branched architecture ensures excellent dispersibility and superior electrical conductivity. Additionally, each branched tip is equipped with Ni−Fe particles, thereby providing numerous catalytic sites which endow them with exceptional catalytic activity for the conversion of polysulfides. The polypropylene (PP) separator modified with Ni−Fe@BCNT interlayer is fabricated as a multifunctional barrier for Li–S batteries. The experimental results demonstrate that Ni−Fe@BCNT interlayer can effectively suppress the shuttle effect of polysulfides and enhance their redox kinetics. The outstanding catalytic ability of Ni−Fe@BCNT interlayer enables batteries with high specific capacities, outstanding rate performance, and remarkable cycling stability. This approach proposed in this work paves a new path for synthesizing BCNTs and shows great potential for scaling up the production of BCNTs to address more demanding applications. [ABSTRACT FROM AUTHOR]

The binder, a critical electrode component, significantly influences lithium‐ion batteries (LIB) performance, yet remains an under‐researched area. The widespread use of polyvinylidene fluoride (PVDF) as a commercial binder is challenged by its surging cost, attributed to limited production and increased demand, highlighting the necessity for alternatives. Here, we synthesize poly (trifluoroethyl methacrylate) (PTFEMA), a polymer with a molecular weight in the million range, through a straightforward radical solution polymerization method, aiming to use it as a cathode binder for LIBs. PTFEMA demonstrate good stability across the typical operating temperatures and voltages, along with robust adhesion to the current collector. Moreover, the PTFEMA outperforms PVDF in terms of electrolyte affinity and lithium‐ion conductivity, thereby achieving capacity and stability comparable to those of its PVDF counterparts. This investigation confirms the homopolymer form of PTFEMA as a compelling alternative to PVDF, representing a valuable exploration of binder technology for LIBs. [ABSTRACT FROM AUTHOR]

We present a novel approach to adjust the symmetry of Au octahedral nanocrystals in two-dimensional superlattices. By modifying the content of free polymeric ligands added in the nanocrystal solution, we achieve Au nanocrystal superlattices with tip-on-tip arrangements that significantly enhance the surface-enhanced Raman spectroscopy performance. [ABSTRACT FROM AUTHOR]

Silicon, serving as an anode material of Li‐ion batteries, offers a theoretical capacity significantly higher than graphite, but its practical application is hindered by poor conductivity, low lithium ion diffusivity, and severe volumetric expansion. Here, a simple and eco‐friendly methodology is proposed to synthesize precisely prelithiated polyacrylic acid binder, optimizing the interface between the binder and micron Si particles. The incorporation of these binders not only mitigates the detrimental effects of volumetric expansion but also enhances mechanical strength, and ionic conductivity of the anode, significantly improving the initial Coulombic efficiency (ICE), cycling stability, and rate performance of micron‐sized Si anodes. This study not only highlights the potential of prelithiated binders in overcoming the limitations of micron‐sized Si anodes but also sets a new benchmark for the development of high‐capacity, eco‐friendly Li‐ion batteries. [ABSTRACT FROM AUTHOR]

The inclusion of colloidal particles into 3D porous constructs to realize heterostructure ensembles enhances surface interactions and energy transfer that can transform the catalytic properties of conventional catalysts. However, assembling hydrophobic colloidal nanoparticles within hydrophilic 3D porous matrices to create tailored heterostructures and catalytic properties is particularly challenging. Here, a modified ligand grafting method is presented to spontaneously assemble CdS inorganic colloidal quantum dots within a metal‐organic framework (MOF) derived porous framework for efficient photocatalytic CO2 reduction. The grafted long chain molecular ligands effectively suppress phase separation and endow a molecular‐recognition effect to form ordered assembly microstructures. The proof‐of‐concept assembly of CdS and Prussian blue analogues (PBA) derived Co3O4 facilitates a high density of heterojunctions formation, improving charge transfer and extended lifetimes of photo‐induced electrons. Consequently, CdS/Co3O4 assembly exhibits exceptionally active and stable photocatalytic CO2 reduction activity, with a CO production rate of 73.9 µmol g−1 h−1 and CO selectivity of 98.9%. Importantly, the ligand grafting method can be generalized to achieve spontaneous assembly of quantum dots within various metal organic framework derived porous scaffolds. This work provides a rational strategy for precise self‐assembly of colloidal nanoparticles within porous microstructures, allowing tailored heterointerfaces for functional materials and applications. [ABSTRACT FROM AUTHOR]

We present a novel method for synthesizing monodisperse, star-shaped FeCoMnOx nanocrystals with tunable concavity. Through liquid–air interfacial assembly, these colloidal nanostars can form two-dimensional superlattices, which are characterized by low packing densities. Notably, the ability to adjust the degree of concavity of nanostars allows for the tuning of the packing symmetry of the assembled superlattices. [ABSTRACT FROM AUTHOR]

Incorporating conductive and porous components as pillaring materials into the interlayers of two‐dimensional (2D) materials offers a solution to the restacking issue and enables the creation of multifunctional hetero‐superstructures. Here, multilayer MXene superlattices intercalated with monolayer mesoporous carbon frameworks (MMCFs) are synthesized by colloidal co‐assembly of MXene Ti3C2Tx nanosheets and Fe3O4 nanoparticles. The intercalated MMCFs not only increase interlayer spacing and create porous channels for fast mass transport but also act as conductive pillars to facilitate electron transfer along the z‐direction. These unique structural features allow for the full utilization of unilamellar MXene, making the resulting Ti3C2Tx/MMCF superlattices particularly suitable for capacitive energy storage in organic electrolytes containing bulky ions. As a demonstration, supercapacitors made from Ti3C2Tx/MMCFs exhibit a volumetric capacitance of 317 F cm−3 in a tetraethylammonium tetrafluoroborate/propylene carbonate electrolyte. Furthermore, on‐chip micro‐supercapacitors (MSCs) fabricated from Ti3C2Tx/MMCFs, using the ionic liquid 1‐ethyl‐3‐methylimidazolium tetrafluoroborate as an electrolyte, achieve an areal energy density of 0.10 mWh cm−2, surpassing that of most state‐of‐the‐art MXene‐based MSCs developed to date. This study not only highlights the significant potential of Ti3C2Tx/MMCFs for efficient capacitive energy storage in organic electrolytes but also introduces a new method for synthesizing 2D porous hetero‐superstructures for various applications. [ABSTRACT FROM AUTHOR]

Members of transition metal dichalcogenides, particularly molybdenum disulfide, have been recognized as promising efficient and durable earth‐abundant catalysts for the hydrogen evolution reaction (HER). Despite the recent significant progress, the HER performance of MoS2 is still far from satisfactory, especially at high current densities. Here, a simultaneous multilevel structural control strategy is reported to cooperatively boost hydrogen evolution on 2H‐MoS2, unlocking its potential for practical hydrogen evolution at ampere‐level current densities. By confining the epitaxial growth of few‐layered, curved MoS2 nanosheets within a tubular mesoporous graphitic framework, one can achieve deliberate structural control of MoS2 across seven orders of magnitude on the length scale. The resulting MoS2@C supertubes, benefiting from their unique structural features across atomic‐to‐microscopic scales, are characterized by abundant edge sites and sulfur vacancies, facilitated charge and mass transport, and rapid gas bubble removal. As a consequence, such MoS2@C supertubes exhibit exceptional high‐current‐density HER activity surpassing previously reported 2H‐MoS2 catalysts and even commercial Pt/C catalysts. This work demonstrates the validity of multilevel structural engineering of 2H‐MoS2 by confinement growth, opening a viable route of developing low‐cost catalysts toward practical hydrogen evolution. [ABSTRACT FROM AUTHOR]