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Self‐assembly of nanomaterials, directed by molecular or supramolecular interactions, is a powerful strategy to build nanoscale devices. Despite many advantages of such solution‐based processes, a big challenge is to realize interparticle ohmic contacts toward facilitated charge transport over a long distance. We report a new concept of primed nanowelding to thread solution‐borne nanoparticles in prescribed assemblies. The process starts with a gap‐specific deposition of Ag2E (E=S, Se) materials in pre‐assembled gold structures, which spontaneously transform into AgAuE semiconductors via directional gold diffusion. Treatment with tributylphosphine generates alloyed Au/Ag welding spots that conductively wire‐up nanoparticles into discrete "molecules" and micron‐long "polymers". This method is compatible with DNA programming and delivers a possible way to solve the problem of the carrier‐transport dilemma in solution‐processed nanostructures for better‐functioning nanodevices. [ABSTRACT FROM AUTHOR]

The unique 2D-layered structure of tin (II) sulfide (SnS) compounds has led to the emergence of strong intensities, showcasing their significant potential in lithium (LIBs) and sodium (SIBs) ion batteries. However, the commercialization process of SnS compounds remain hindered due to the poor cycle stability caused by its substantial volume expansion during cycling in battery applications. In this study, a simple and scalable synthesis of ultra-thin composite with a well-connected structure SnS/N-doped carbon/SnS (SnS/NC/SnS) is reported. The structure is directly derived from layered tin chalcogenides (A 2 Sn 3 S 7 ·xH 2 O, where A represents an organic cation). Within this configuration, SnS nanosheets are decorated on the N-doped carbon material. The composite exhibits an expanded layer of 9.7 Å, enabling rapid movement of Na+ ions (approximately 7 times the diffusion coefficient of bulk SnS). This expansion also aids in accommodating volume changes during the discharging and charging processes. Concurrently, theoretical calculations demonstrate that the structure maintains a relatively stable state at the interlayer spacing mentioned. The SnS/NC/SnS composite material exhibited significant potential for application in both SIBs and LIBs. In SIBs, it demonstrated excellent long-term cyclic stability, maintaining a capacity of 190 mA h g−1 even under high current density conditions of 2.5 A g−1 after 300 cycles. In LIBs, it exhibit a superior discharge capacity of 990 mA h g−1 and retains 94.1 % of its capacity after 150 cycles at 0.2 A g−1. Notably, this synthesis method is versatile, as the interlayer spacing can be adjusted by varying the type of organic cations used in the process. • SnS/NC/SnS is synthesized in situ via directly derivation of layered tin chalcogenides. • N doped carbon functioning as "bridge" to enhance the electrical conductivity. • The enlarged interlayer buffers the volume expansion and improves the diffusion coefficient of Na+. • The interlayer can be accommodated by adjusting the kind of organic cations. • SnS/NC/SnS composite exhibits a tremendously boosted electrochemical performance. [ABSTRACT FROM AUTHOR]

One of the challenges in developing advanced dye-sensitized solar cells (DSSCs) is the pursuit of cost-effective and robust counter electrodes (CEs). We present here the successful synthesis of binary Pt x M 100−x (M = Ni, Co, Fe) alloy nanostructures on Ti foil by a facile and environmental-friendly strategy for utilization as CEs in liquid-junction DSSCs. Due to the reasonable charge-transfer ability and excellent electrocatalytic activity, the resultant DSSC yields a promising power conversion efficiency (PCE) of 6.42% with binary Pt 0.28 Ni 99.72 CE in comparison with 6.18% for pristine Pt CE based device. The easy synthesis, cost-effectiveness, and good electrocatalytic property may help the Pt 0.28 Ni 99.72 nanostructure stand out as an alternative CE electrocatalyst in a DSSC. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mesoporous TiO2 hierarchical tubular superstructure (MTNHTS) has been successfully synthesized. [•] The structure is 1–2μm in diameter and 6–10μm in length, which consists of mesoporous nanosheets. [•] The growth mechanism of such a unique structure has been discussed. [•] The photocatalytic activity and lithium ion batteries performance are investigated. [•] MTNHTS manifest enhanced performances of photocatalysis and Li-ion batteries superior to P25. [ABSTRACT FROM AUTHOR]

Highlights: [•] Controllable synthesis of core–shell structured Fe3O4@SiO2@TiO2-Ag magnetic nanocomposite. [•] The unique nanostructure of Fe3O4@SiO2@TiO2-Ag can improve the total photocatalytic performance. [•] An easy magnetically separable and recoverable process. [Copyright &y& Elsevier]

Abstract To develop efficient nonprecious electrocatalysts for the oxygen reduction reaction (ORR) on cathode in fuel cell is urgently required. Herein, a promising coral-like N,S-codoped hierarchical porous carbon with supported cobaltous sulfide nanoparticles (Co x S y /NS-HPC) with different molar ratio of S:Co was successfully fabricated via an economic method. The role of thiourea in the preparation process was found to be triplex. It is not only as a sulfur source, but also as sulfur-nitrogen dopant, and most importantly it participates in the formation of the hierarchical porous carbon which will reduce the diffusion resistance of the reactants and expose more active sites. Benefited from the carbon support, the hybrid architecture CoS 1.097 /NS-HPC (S:Co = 3:1) possesses high specific surface area (549 m2/g) and more active sites, as result it was developed as decent ORR electrocatalyst for fuel cell. Surprisingly, we found that CoS 1.097 /NS-HPC provides a more positive onset potential, higher cathodic current density and half-wave potential in alkaline media than CoS 1.097 NPs and CoS 1.097 supported on conventional mesoporous carbon (CoS 1.097 /MC). More importantly, compared with commercial Pt/C, CoS 1.097 /NS-HPC manifests higher current density, better durability, and more excellent methanol tolerance. Graphical abstract Image 1 Highlights • Nonprecious coral-like cobaltous sulfide/N,S-codoped carbon with hierarchical pores was synthesized. • The ORR activities of Co x S y /NS-HPC synthesized in different molar ratio of S:Co were investigated by CV and RRDE. • The catalyst CoS 1.097 /NS-HPC synthesized with S:Co of 3:1 exhibits the best ORR performance. • CoS 1.097 /NS-HPC is superior to Pt/C in limiting current density, durability and methonal tolerance. [ABSTRACT FROM AUTHOR]