Vortex‐Pattern Self‐Assembly in Mn‐Doped ZnSe Nanorods

Abstract

Spontaneous patterning of anisotropic nanostructures into ordered assemblies remains a challenging quest, which requires controlled innovative approaches. One way to achieve such ordering of 1D nanorods is by manipulating the varieties of interactions (attractive and repulsive forces) present in colloidal solutions of anisotropic nanocrystals. The other ingenuous pathway is solvent-evaporation-mediated self-organization of the 1D nanorods. By following the second protocol, we have achieved exclusive pillar self-assembled patterns of visible-light-emitting Mn-doped ZnSe nanorods. The nanorods also exhibit intriguing vortex patterning observed by directional solvent evaporation from the nanorod solution. The effect of solvent evaporation to generate such unique morphologies on the TEM grid is discussed and the reported procedure to obtain the assembled patterns of visible-light-emitting, doped nanorods might be useful for future technological applications.

Blue-Emitting CsPbBr3 Perovskite Quantum Rods and Their Wide-Area 2D Self-Assembly

“…Figure 1d presents a vortex type of such an assembly having a center where the assembly nucleated. 31 More TEM images of the self-assembly are provided in Figures S2−S4 in the Supporting Information. Rotation of the grid confirmed the vortex-type assembly as the center moved from one place to another with the grid rotation (Figure S5).…”

“…The 2D assembly in Figure a covered more than 1 μm 2 area, and from the images in Figure b,c, these nanostructures were observed as nanorod self-assemblies. Figure d presents a vortex type of such an assembly having a center where the assembly nucleated . More TEM images of the self-assembly are provided in Figures S2–S4 in the Supporting Information.…”

Macroscopic Vortex-Induced Optical Activity in Silver Nanowires

“…19−21 In fluid dynamics, a vortex is a region within a fluid where the flow mostly spins around an imaginary axis, either straight or curved. 22,23 Vortex and stirring-induced chirality has been established and reported for several organic achiral molecular and supramolecular systems such as ionic oligomers, 24 polymers, 25 proteins, 26,27 liquid crystals, 28,29 and for selfassemblies of supramolecular aggregates. 23,29−39 The vortexinduced chirality effect has mainly been observed and reported for self-assembled structures such as J-aggregate systems.…”

“…49 Using directional solvent evaporation from Mn-doped ZnSe nanorods, vortex patterning of semiconducting nanorods was realised. 22 It has also been demonstrated that rotating vortex flows can be used to achieve chiral separation at the micro-and nanoscales. 20,50 Here, we report the macroscopic optical activity effects in suspensions of plasmonic silver nanowires (Ag NWs) induced by vortex stirring.…”

“…Clockwise (CW) and counter-CW vortexing has also been used to tune the chirality of graphene oxide and transfer a handedness to achiral host molecules (tetrakis­(4- N -methyl pyridyl)­porphyrins) . Using directional solvent evaporation from Mn-doped ZnSe nanorods, vortex patterning of semiconducting nanorods was realised . It has also been demonstrated that rotating vortex flows can be used to achieve chiral separation at the micro- and nanoscales. , …”