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The use of nanoporous metals as catalysts has attracted significant interest in recent years. Their high‐curvature, nanoscale ligaments provide not only high surface area but also a high density of undercoordinated step edge and kink sites. However, their long‐term stability, especially at higher temperatures, is often limited by thermal coarsening and the associated loss of surface area. Herein, it is demonstrated that the nanoscale morphology of nanoporous Cu can be regenerated by applying oxidation/reduction cycles at 250 °C. Specifically, the morphological evolution and H₂dissociation activity of hierarchical nanoporous Cu catalysts doped with Ti during structural rearrangement triggered by oxidative and reductive atmospheres at elevated temperatures are studied. In addition to coarsening of the structure at elevated temperatures, oxidation at 400 °C causes an expansion of the ligaments. Subsequent reduction at 400 °C leads to the formation of particles and a drop in the H₂dissociation activity compared the fresh catalyst. However, performing the redox cycle at 250 °C reverses coarsening and boosts the H₂dissociation activity for the hydrogen–deuterium (H₂–D₂) reaction. Herein, the possibility to reverse coarsening is demonstrated, thereby mitigating the loss of activity frequently observed in nanoporous catalysts. 

Abstract The exploration of 1D magnetism, frequently portrayed as spin chains, constitutes an actively pursued research field that illuminates fundamental principles in many‐body problems and applications in magnonics and spintronics. The inherent reduction in dimensionality often leads to robust spin fluctuations, impacting magnetic ordering and resulting in novel magnetic phenomena. Here, structural, magnetic, and optical properties of highly anisotropic 2D van der Waals antiferromagnets that uniquely host spin chains are explored. First‐principle calculations reveal that the weakest interaction is interchain, leading to essentially 1D magnetic behavior in each layer. With the additional degree of freedom arising from its anisotropic structure, the structure is engineered by alloying, varying the 1D spin chain lengths using electron beam irradiation, or twisting for localized patterning, and spin textures are calculated, predicting robust stability of the antiferromagnetic ordering. Comparing with other spin chain magnets, these materials are anticipated to bring fresh perspectives on harvesting low‐dimensional magnetism. 

Abstract The manipulation of carbon nitride (CN) structures is one main avenue to enhance the activity of CN‐based photocatalysts. Increasing the efficiency of photocatalytic heterogeneous materials is a critical step toward the realistic implementation of sustainable schemes for organic synthesis. However, limited knowledge of the structure/activity relationship in relation to subtle structural variations prevents a fully rational design of new photocatalytic materials, limiting practical applications. Here, the CN structure is engineered by means of a microwave treatment, and the structure of the material is shaped around its suitable functionality for Ni dual photocatalysis, with a resulting boosting of the reaction efficiency toward many CX (X = N, S, O) couplings. The combination of advanced characterization techniques and first‐principle simulations reveals that this enhanced reactivity is due to the formation of carbon vacancies that evolve into triazole and imine N species able to suitably bind Ni complexes and harness highly efficient dual catalysis. The cost‐effective microwave treatment proposed here appears as a versatile and sustainable approach to the design of CN‐based photocatalysts for a wide range of industrially relevant organic synthetic reactions.