Spontaneous Formation of Nanochains from Triangular Silver Nanoplates

Self-assembly represents an energy-efficient way toward the configurable design of functional nanomaterials. In this paper, triangular silver nanoplates are shown to spontaneously form anisotropic assemblies in the solution. Nanochains consisting of face-to-face aligned nanoplates can reach hundreds of nanometers long after the dispersion of triangular silver nanoplates is allowed to age at room temperature for 1 week. The preferred face-to-face attachment is attributed to the maximized van der Waals attraction for a thermodynamically stable configuration as opposed to side-by-side attachment. Time-dependent UV-vis spectra show a gradual blue-shift along with the increase of aging time, indicating a likely stepwise growth of nanochains. The peak shift is however found to be much smaller than the results of finite-difference time-domain simulations based on the same sized nanoplates with ideally concentric face-to-face placement. Such discrepancy may be attributed to the possible misalignment and size variations of stacking nanoplates.