Harnessing screw dislocations in shell-lattice metamaterials for efficient, stable electrocatalysts.

Developing highly active and robust catalysts remains a critical challenge for the industrial realization and implementation of nitrate reduction. Here, we proposed a screw dislocation-mediated three-dimensional (3D) printing strategy for scalable, integrated manufacturing of metamaterial catalysts. Specifically, screw dislocation was introduced into the 3D printing process to mediate the simultaneous synthesis of 3D architecture and chiral surface nanostructures, effectively eliminating conventional heterointerfaces.

The structural origin of extraordinary plasticity in polycrystalline semiconductors with low symmetry.

Ductile polycrystals are usually metals with high-symmetry structures that provide multiple slip systems to coordinate the synergetic deformation of adjacent grains. However, while exceptional plasticity was recently discovered in a series of low-symmetry semiconductors, their deformation mechanism remains mysterious. Here, taking monoclinic AgSSe as a case study, we show that the inherent high-symmetry anion sublattice with a quasi-body-centered cubic (bcc) structure is embedded in the monoclinic matrix.

Effect of Grain Geometry on the Stability of Polycrystalline Pt at the Nanoscale.

Kelvin polycrystals with geometrical packing of tetrakaidecahedra grains were regarded as the only possible stable polycrystalline structures in solids. By intensive plastic straining of Pt, we identified the existence of Kelvin polycrystals with 4 nm grains and Schwarz crystals of 2-3 nm in size connected by minimal-surface grain boundaries, both constrained by twins. We found Schwarz crystals remained stable up to 1923 K, nearly 94% of the melting point of Pt, well above the stability limit of the Kelvin polycrystals (1373 K).