Artificial reconstruction of fibre-shaped cellular constructs could greatly contribute to tissue assembly in vitro. Here we show that, by using a microfluidic device with double-coaxial laminar flow, metre-long core-shell hydrogel microfibres encapsulating ECM proteins and differentiated cells or somatic stem cells can be fabricated, and that the microfibres reconstitute intrinsic morphologies and functions of living tissues. We also show that these functional fibres can be assembled, by weaving and reeling, into macroscopic cellular structures with various spatial patterns. Moreover, fibres encapsulating primary pancreatic islet cells and transplanted through a microcatheter into the subrenal capsular space of diabetic mice normalized blood glucose concentrations for about two weeks. These microfibres may find use as templates for the reconstruction of fibre-shaped functional tissues that mimic muscle fibres, blood vessels or nerve networks in vivo.

Polycondensation via Pd-catalyzed cross-dehydrogenativecoupling reaction of 2,2′,3,3′,5,5′,6,6′-octafluorobiphenyl with thiophene analogues was studied. The synthetic protocol, in which employment of prefunctionalized starting monomers was fully avoided, allowed straightforward access to an alternating π-conjugated polymer. The addition of K 2 CO 3 to the catalytic system promotes the cross-coupling reaction and suppresses the undesired homocoupling reaction, producing the corresponding donor− acceptor type π-conjugated polymers with minor homocoupling defects. The reaction also proceeded using O 2 as the terminal oxidant, resulting in lower loading of the Ag oxidant. The obtained polymer was evaluated as an emitting material for an organic light-emitting diode.

The mechanism of the Pd/Ag-dual-catalyzed cross dehydrogenative coupling (CDC) between perfluoroarenes and thiophenes was clarified. The exact role of the catalytic resting state of the homo biaryl-Pd(II) complex, which was previously overlooked in Pd/Ag-dualcatalyzed CDC, was carefully investigated. Detailed experimental studies indicated that a homo biaryl-Pd(II) complex occurred in the catalytic off-cycle as a resting state and prevented the homocoupling of perfluoroarenes. In addition, these studies indicated that the C-H bond activation steps of perfluoroarenes and thiophenes proceeded by different mechanisms. While the C-H bond

Jacketed supramolecular strand: Meter‐long supramolecular strands were obtained by encapsulating them in polymer gels using a microfluidic channel (see picture). The nanofibers in the strands are self‐assembled and aligned under the laminar flow conditions. Their mechanical strength was sufficiently high to allow their patterning onto a substrate and use them as a template for synthesizing an insoluble, conductive polymer.

The introduction of pyridinic nitrogen (pyri-N) into carbon-based electrocatalysts for the oxygen reduction reaction is considered to create new active sites. Herein, the role of pyri-N in such catalysts was investigated from a mechanistic viewpoint using carbon black (CB)-supported pyri-N-containing molecules as model catalysts; the highest activity was observed for 1,10-phenanthroline/CB. X-ray photoemission spectroscopy showed that in acidic electrolytes, both pyri-N atoms of 1,10-phenanthroline could be protonated to form pyridinium ions (pyri-NH +). In O 2-saturated electrolytes, one of the pyri-NH + species was reduced to pyri-NH upon the application of a potential; no such reduction was observed in N 2-saturated electrolytes. This behavior was ascribed to electrochemical reduction of pyri-NH + occurring simultaneously with the thermal adsorption of O 2 , as supported by DFT calculations. According to these calculations, the coupled reduction was promoted by hydrophobic environments.

Considerable efforts have been devoted to developing oxygen evolution reaction (OER) catalysts based on transition metal oxides. Polyoxometalates (POMs) can be regarded as model compounds of transition metal oxides, and cobalt-containing POMs (Co-POMs) have received significant interest as candidates. Nanocomposites based on Co-POMs have been reported to show high OER activities due to synergistic effects among the components; however, the role of each component is unclear due to its complex structure. Herein, we utilize porous ionic crystals (PICs) based on Co-POMs, which enable a composition–structure–function relationship to be established to understand the origin of the synergistic catalysis. Specifically, a Keggin-type POM [α-CoW12O40]6– and a Cr complex [Cr3O­(OOCCH2CN)6(H2O)3]+ are implemented as PIC building blocks for the OER under nonbasic conditions. The potentially OER-active but highly soluble [α-CoW12O40]6– was successfully anchored in the crystalline PIC matrix via Coulomb interactions and hydrogen bonding induced by polar cyano groups of the Cr complex. The PIC exhibits efficient and sustained OER catalytic activity, while each building block is inactive. The Tafel slope of the linear sweep voltammetry curve and the relatively large kinetic isotope effect value suggest that elementary steps closely related to the OER rate involve single-electron and proton transfer reactions. Electrochemical and spectroscopic studies clearly show that the synergistic catalysis originates from the charge transfer from the Cr complex to [α-CoW12O40]6–; the increased electron density of [α-CoW12O40]6– may increase its basicity and accelerate proton abstraction as well as enhance electron transfer to stabilize the reaction intermediates adsorbed on [α-CoW12O40]6–.

is an associate professor at the department of basic science, The University of Tokyo. She received her PhD in applied chemistry from The University of Tokyo (2002). She has worked as a postdoc and assistant professor at the department of applied chemistry, The University of Tokyo (Prof. Mizuno group) and moved to the current position (2009 Oct). She has also worked as a JST-PRESTO researcher "Hyper-nanospace design toward innovative functionality" (20132017). Her work focuses on the synthesis of functional solid-state materials based on polyoxometalates. Yuto Shimoyama is a PhD student at The University of Tokyo. He received his Bachelor's degree (2017, catalyst and surface science group) and master's degree (2019, Prof. Kanbara group) in engineering from University of Tsukuba. His current research focuses on the synthesis of porous ionic crystals and their catalytic applications at the Uchida group.

A redox‐active ionic crystal based on a Dawson‐type polyoxometalate (POM) [α‐P2WVI18O62]6− is utilized to form and stabilize small mixed‐valence luminescent silver clusters without the aid of protecting ligands at room temperature. A reduced ionic crystal of Cs3H5[Cr3O(OOCH)6(etpy)3]3[α‐P2WV5WVI13O62] ⋅ 5H2O (etpy=4‐ethylpyridine) is formed by a cation‐coupled electron‐transfer (CCET) reaction with sodium ascorbate as a reducing reagent to provide electrons and Cs+ as counter cations of POM. Then, silver is introduced via ion‐exchange between Cs+ and Ag+ jointly with CCET reaction: X‐ray photoelectron spectroscopy and elemental analysis show that the ionic crystal is oxidized via electron‐transfer from the POM (W5+) to Ag+, and [Ag01.5AgI1.5]H4.5[Cr3O(OOCH)6(etpy)3]3[α‐P2WV3WVI15O62] ⋅ 7H2O is formed. Photoluminescence and X‐ray absorption fine structure suggest that the silver species exist as mixed‐valence luminescent clusters with an average formula of [Ag4]2+ probably in a tetrahedral geometry.