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Phosphorene nanoribbons (PNRs) have inspired strong research interests to explore their exciting properties that are associated with the unique two‐dimensional (2D) structure of phosphorene as well as the additional quantum confinement of the nanoribbon morphology, providing new materials strategy for electronic and optoelectronic applications. Despite several important properties of PNRs, the production of these structures with narrow widths is still a great challenge. Here, a facile and straightforward approach to synthesize PNRs via an electrochemical process that utilize the anisotropic Na⁺diffusion barrier in black phosphorus (BP) along the [001] zigzag direction against the [100] armchair direction, is reported. The produced PNRs display widths of good uniformity (10.3 ± 3.8 nm) observed by high‐resolution transmission electron microscopy, and the suppressedB_2gvibrational mode from Raman spectroscopy results. More interestingly, when used in field‐effect transistors, synthesized bundles exhibit the n‐type behavior, which is dramatically different from bulk BP flakes which are p‐type. This work provides insights into a new synthesis approach of PNRs with confined widths, paving the way toward the development of phosphorene and other highly anisotropic nanoribbon materials for high‐quality electronic applications.

Chalcogenide superionic sodium (Na) conductors have great potential as solid electrolytes (SEs) in all‐solid‐state Na batteries with advantages of high energy density, safety, and cost effectiveness. The crystal structures and ionically conductive properties of solid Na‐ion conductors are strongly influenced by synthetic approaches and processing parameters. Thus, understanding the synthesis process is essential to control the structures and phases and to obtain Na‐ion conductors with desirable properties. Thanks to the high‐flux and deep‐penetrating time‐of‐flight neutron diffraction (ND), in‐situ experiments were able to track real‐time structural changes of two chalcogenide SEs (Na₃SbS₄and Na₃SbS_3.5Se_0.5) during the solid‐state synthesis. For these two conductors, the ND results revealed a fast one‐step reaction for the synthesis and the molten process when heating up, and the recrystallization as well as the cubic‐to‐tetragonal phase transition up on cooling. Moreover, Se‐doping was found to influence the reaction temperatures, lattice parameter, and structure stability based on neutron experimental observations and theoretical simulation. This work presents a detailed structural study using in‐situ ND technology for the solid synthesis process of chalcogenide Na‐ion conductors, beneficial for the design and synthesis of new solid‐state conductors.

Mesoporous TiO₂coating on carbon–sulfur cathode with simple electrical contact for high capacity Li–S battery.