Role of particle size and surface functionalisation on the flexibility behaviour of switchable metal–organic framework DUT-8(Ni)

Abstract

Flexible MOF nanoparticles, i.e. MOF nanoparticles that change their structure upon external stimuli such as guest uptake, are promising for numerous applications including advanced gas adsorption, drug delivery and sensory...

Impact of Crystal Size and Morphology on Switchability Characteristics in Pillared-Layer Metal-Organic Framework DUT-8(Ni)

“…The same chemicals present in the synthetic mixture ensure the same terminating groups on the crystal outer surface, which is not necessarily the case if modulators, differing in functional groups, are used to influence the morphology (as it is the case for samples A, B, and C vs. D vs. E). The impact of the surface termination on the flexibility of DUT-8(Ni), however, has been recently analyzed by the group of Düren (Thompson et al, 2020 ).…”

From Macro- to Nanoscale: Finite Size Effects on Metal–Organic Framework Switchability

“…Hence, on a volumetric basis, the energetics of switchable MOF phase transitions are of an order of magnitude comparable with those of simple binary compounds, and pronounced crystal size effects according to Gibbs-Thomson rules should be expected normally below 100 nm. For slabs below 10 nm in thickness, the surface contribution has been estimated to reduce Δ op cp E V by 10-40 kJ/mol depending on surface termination [82]. This contribution will become negligible at slab size >500 nm, indicating that shape memory effects observed at such length scales cannot be solely attributed to the Gibbs-Thomson effect.…”

Competing phases in the room-temperature M2(2,6-ndc)2(dabco) metal–organic framework thin film synthesis

“…29,30,49 The crystal sizes, linked to different synthesis conditions, were also found to influence the flexibility and guest-response properties of DUT-8(Ni), with the smaller particle sizes (below B500 nm) exhibiting a rigid response. 35,[49][50][51][52] For flexible DUT-8, changes in their crystal structure could be initiated by the presence of different solvent or gas molecules in the pores due to the varying interaction between the guest and the MOF. 28 Prior to thin film synthesis, we performed the synthesis of M 2 (2,6-ndc) 2 (dabco) in bulk powder form at room temperature by layering the metal salt and ligands dissolved in ethanol.…”