Bambus[n]uril synthesis may be challenging, and it is frequently achieved with low purity and low yields. We have studied the effect of different anions on the synthesis of bambus[6]uril, especially in terms of yield, exploring template effects driven by anions in the reaction medium. The influence of the anions is evident on such syntheses and ClO4− particularly led to unprecedented synthesis yields. Computational calculations have also been used to elucidate the influence of anions on cyclization process.

Este trabalho apresenta uma rota alternativa para a preparação de nanodiscos de iodeto de chumbo (ca. 50-340 × 7Å, diâmetro × espessura) utilizando o macrocíclico cucurbit[7]urila como molde de síntese e agente estabilizante. Estas nanopartículas apresentam um deslocamento para o azul de gap óptico consistente com seu tamanho reduzido e confinamento quântico 1D. Suas espessuras são compatíveis com a de uma camada de iodeto de chumbo esfoliado, indicando que cucurbit[7]urila impede a formação de estruturas lamelares e limita o crescimento das nanopartículas. A estrutura, a morfologia e as propriedades destes discos foram verificadas por difratometria de raios X em pó (XRD), espectroscopia no UV-Visível, microscopia de força atômica (AFM), microscopia eletrônica de varredura com análise de fluorescência de raios X por dispersão de energia (SEM-EDS) e microscopia eletrônica de transmissão de alta resolução (HRTEM).

This work presents an alternative route for the preparation of heavy metal iodide nanoparticles, particularly lead iodide nanodisks (ca. 50-340 × 7 Å, diameter × thickness), using the macrocycle cucurbit[7]uril as a synthetic template and stabilizing agent. These nanoparticles exhibit an optical-gap blue shift consistent with their small size and 1D quantum confinement. Their thicknesses are compatible with an exfoliated single layer of lead iodide, indicating that cucurbit[7]uril, preventing the stacking and formation of tactoids, thus limiting nanoparticles growth in the z direction. The structure, morphology and properties of these disks were analyzed by X-ray powder diffractometry (XRD), UV-Visible spectroscopy, atomic force microscopy (AFM), scanning electron microscopy with analysis of energy dispersive X-ray fluorescence (SEM-EDS) and high resolution transmission electron microscopy (HRTEM).