In this paper, the results of the investigation the growth of the zinc oxide nanocrystals during chemical bath deposition will be presented. The influence of the chemical compounds on the shape and the composition of the nanostructures were researched. Chemical compounds like hexamethylenetetramine, zinc nitrate hexahydrate, urea and ascorbic acid were used in experiments.

Pyridine-modified COF-10 exhibits enhanced stability in humid air relative to un-modified COF-10. Solid state NMR and computational studies were used to probe the nature of pyridine interactions with the framework. We propose two models for pyridine-framework interactions with different stabilities.

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The kinetics of the irreversible phase conversion of covalent organic frameworks-1 (COF-1) has been investigated using time-resolved, in situ environmental X-ray diffraction (EXRD) and modeled with the Avrami–Erofe’ev model. Tightly fitting mesitylene solvent is found to be present in both the AB staggered and AA eclipsed polymorphs, which plays a key role in the phase change. Solid-state NMR (SSNMR) showed the presence of discrete dipolar coupling between residual mesitylene solvent and the framework in both polymorphs, indicative of a host–guest adsorptive interaction. Binding energy calculations indicate two different adsorbed mesitylene configurations in the AB and AA phases, both with short distances to the framework pore walls to generate the observed dipolar coupling. The mechanism of phase change has been illustrated using molecular dynamics simulations and was found to be a displacive transition from AB staggered to AA eclipsed COF-1 structures, which was made possible due to low in-plane shear modulus of 2D COFs. Our findings highlight the polymorphic nature of COF-1 material mediated by the interactions with guest molecules and the irreversibility for polymorph formation and conversion.