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Thermoset polymers are known for their superior thermomechanical properties, but the chemical crosslinking typically leads to intractability. This is reflected in the great differences between thermoset and thermoplastic shape-memory polymers; the former exhibit a robust shape memory but are not capable of redefining the permanent shape. Contrary to current knowledge, we reveal here that a classical thermoset shape-memory polyurethane is readily capable of permanent reshaping (plasticity) after a topological network rearrangement that is induced by transcarbamoylation. By employing the Jianzhi technique (also known as kirigami), unexpected shape-shifting versatility was observed for this otherwise classical material. As the essential carbamate moiety in polyurethanes is one of the most common polymer building units, we anticipate that our finding will have significant benefits beyond shape shifting. [ABSTRACT FROM AUTHOR]

Alkaline water electrolysis (AWE) plays a crucial role in the realization of a hydrogen economy. The design and development of efficient and stable bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal to achieving high‐efficiency AWE. Herein, WC1‐x/Mo2C nanoparticle‐embedded carbon nanofiber (WC1‐x/Mo2C@CNF) with abundant interfaces is successfully designed and synthesized. Benefiting from the electron transfer behavior from Mo2C to WC1‐x, the electrocatalysts of WC1‐x/Mo2C@CNF exhibit superior HER and OER performance. Furthermore, when employed as anode and cathode in membrane electrode assembly devices, the WC1‐x/Mo2C@CNF catalyst exhibits enhanced catalytic activity and remarkable stability for 100 hours at a high current density of 200 mA cm−2 towards overall water splitting. The experimental characterizations and theoretical simulation reveal that modulation of the d‐band center for WC1‐x/Mo2C@CNF, achieved through the asymmetric charge distribution resulting from the built‐in electric field induced by work function, enables optimization of adsorption strength for hydrogen/oxygen intermediates, thereby promoting the catalytic kinetics for overall water splitting. This work provides promising strategies for designing highly active catalysts in energy conversion fields. [ABSTRACT FROM AUTHOR]

Die traditionelle chinesische Kunst des Scherenschnitts, Jianzhi, führt zu wunderschönen und komplexen Mustern. In der Zuschrift auf S. 11593 ff. verwenden Q. Zhao, T. Xie et al. die Jianzhi ‐ Technik, um klassische duroplastische Polyurethane mit komplexen dreidimensionalen Formen zu erhalten. Das duroplastische Polymer zeichnet sich durch seine intrinsische Plastizität aus und kann durch eine topologische Netzwerk ‐ Reorganisation, die durch Transcarbamoylierung ausgelöst wird, permanent und wiederholt umgeformt werden. [ABSTRACT FROM AUTHOR]