Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
Nat Nanotechnol. 2013 Sep;8(9):676-81. doi: 10.1038/nnano.2013.158. Epub 2013 Aug 18.
When organic molecules are tethered onto non-spherical nanoparticles, their chemical properties depend on the particles' local curvature and shape. Based on this observation, we show here that it is possible to engineer chemical patchiness across the surface of a non-spherical nanoparticle using a single chemical species. In particular, when acidic ligands are used, regions of the particle surface with different curvature become charged at different pH values of the surrounding solution. This interplay between particle shape and local electrostatics allows for fine control over nanoscale self-assembly leading to structures with varying degrees of complexity. These structures range from particle cross-stacks to open-lattice crystals, the latter with pore sizes on the order of tens of nanometres, that is, at the lower synthetic limits of metallic mesoporous materials.
当有机分子被束缚在非球形纳米颗粒上时，它们的化学性质取决于颗粒的局部曲率和形状。基于这一观察，我们在这里表明，使用单一化学物质在非球形纳米颗粒的表面上实现化学不均匀性是可能的。具体来说，当使用酸性配体时，具有不同曲率的颗粒表面区域在周围溶液的不同 pH 值下带电荷。这种颗粒形状和局部静电之间的相互作用允许对纳米级自组装进行精细控制，从而导致具有不同复杂程度的结构。这些结构的范围从颗粒交叉堆叠到开放式晶格晶体，后者的孔径约为数十纳米，即处于金属介孔材料的较低合成极限。
