Search for: All records

Binary nanoparticle superlattices (BNSLs) comprised of polymer-grafted shaped nanoparticles enable the construction of new isotropic mesomaterial. 

Abstract Checkerboard lattices—where the resulting structure is open, porous, and highly symmetric—are difficult to create by self-assembly. Synthetic systems that adopt such structures typically rely on shape complementarity and site-specific chemical interactions that are only available to biomolecular systems (e.g., protein, DNA). Here we show the assembly of checkerboard lattices from colloidal nanocrystals that harness the effects of multiple, coupled physical forces at disparate length scales (interfacial, interparticle, and intermolecular) and that do not rely on chemical binding. Colloidal Ag nanocubes were bi-functionalized with mixtures of hydrophilic and hydrophobic surface ligands and subsequently assembled at an air–water interface. Using feedback between molecular dynamics simulations and interfacial assembly experiments, we achieve a periodic checkerboard mesostructure that represents a tiny fraction of the phase space associated with the polymer-grafted nanocrystals used in these experiments. In a broader context, this work expands our knowledge of non-specific nanocrystal interactions and presents a computation-guided strategy for designing self-assembling materials. 

Abstract Sodium all‐solid‐state batteries (NaSSBs) with an alloy‐type anode (e.g., Sn and Sb) offer superior capacity and energy density compared to hard carbon anode. However, the irreversible loss of Na⁺at the alloy anode during the initial cycle results in diminished capacity and stability, impairing full‐cell performance. This study presents an easy‐to‐implement cathode presodiation strategy by employing a Na‐rich material to address these challenges. Leveraging the high theoretical capacity and suitable voltage window, Na₂S is chosen as the Na donor, which is activated by creating a mixed electron‐ion conducting network, delivering a high capacity of 511.7 mAh g⁻¹. By adding a small amount (i.e., 3 wt.%) of Na₂S to the cathode composite, a NaCrO₂|| Sn full cell demonstrated capacity improvement from 90.8 to 118.2 mAh g⁻¹(based on cathode mass). The capacity‐balanced full cell can thus cycle to more than 300 times with >90% capacity retention. This work provides a practical solution to enhance the full‐cell performance and advance the transformation from half‐cell to full‐cell applications of NaSSBs.