Patchy metal nanoparticles with polymers: controllable growth and two-way self-assembly
Patchy metal nanoparticles with polymers: controllable growth and two-way self-assembly
复制标题
具有聚合物的片状金属纳米颗粒：可控生长和双向自组装
作者：
Duan, Hanyi;Malesky, Tessa;Wang, Janet;Liu, Chung-Hao;Tan, Haiyan;Nieh, Mu-Ping;Lin, Yao;He, Jie
我们报道了一种新设计的聚合物贴片金纳米颗粒（AuNPs），在它们的方向和强度方面具有可控的粒子间相互作用。在配体交换不足的条件下，通过疏水性驱动表面脱湿制备了片状AuNPs （pAuNPs）。利用pAuNPs的暴露表面作为种子，在保持聚合物结构域大小的同时，通过种子介导的方式进行了高度可控的AuNPs生长。在配体的引导下，这些pAuNPs可以沿暴露表面（头对头）或聚合物贴片表面（尾对尾）定向自组装。控制pAuNPs的表面不对称/覆盖为平衡粒子间相互作用（吸引与排斥）提供了一个重要的工具，从而进一步将组装的纳米结构调整为簇和纳米链。自组装途径在确定pAuNPs的粒子间距离和等离子体耦合中起关键作用。我们的研究结果为具有有趣光学性质的分层纳米材料的各向异性构建块的定向自组装提供了新的范例。
We report a new design of polymer-patched gold nanoparticles (AuNPs) with controllable interparticle interactions in terms of their direction and strength. Patchy AuNPs (pAuNPs) are prepared through hydrophobicity-driven surface dewetting under deficient ligand exchange conditions. Using the exposed surface on pAuNPs as seeds, a highly controllable growth of AuNPs is carried out via seed-mediated growth while retaining the size of polymer domains. As guided by ligands, these pAuNPs can self-assemble directionally in two ways along the exposed surface (head-to-head) or the polymer-patched surface of pAuNPs (tail-to-tail). Control of the surface asymmetry/coverage on pAuNPs provides an important tool in balancing interparticle interactions (attraction vs. repulsion) that further tunes assembled nanostructures as clusters and nanochains. The self-assembly pathway plays a key role in determining the interparticle distance and therefore plasmon coupling of pAuNPs. Our results demonstrate a new paradigm in the directional self-assembly of anisotropic building blocks for hierarchical nanomaterials with interesting optical properties.