A Matter of Size and Placement: Varying the Patch Size of Anisotropic Patchy Colloids

Abstract

Non-spherical colloids provided with well-defined bonding sites—often referred to as patches—are increasingly attracting the attention of materials scientists due to their ability to spontaneously assemble into tunable surface structures. The emergence of two-dimensional patterns with well-defined architectures is often controlled by the properties of the self-assembling building blocks, which can be either colloidal particles at the nano- and micro-scale or even molecules and macromolecules. In particular, the interplay between the particle shape and the patch topology gives rise to a plethora of tilings, from close-packed to porous monolayers with pores of tunable shapes and sizes. The control over the resulting surface structures is provided by the directionality of the bonding mechanism, which mostly relies on the selective nature of the patches. In the present contribution, we investigate the effect of the patch size on the assembly of a class of anisotropic patchy colloids—namely, rhombic platelets with four identical patches placed in different arrangements along the particle edges. Larger patches are expected to enhance the bond flexibility, while simultaneously reducing the bond selectivity as the single bond per patch condition—which would guarantee a straightforward mapping between local bonding arrangements and long-range pattern formation—is not always enforced. We find that the non-trivial interplay between the patch size and the patch position can either promote a parallel particle arrangement with respect to a non-parallel bonding scenario or give rise to a variety a bonded patterns, which destroy the order of the tilings. We rationalize the occurrence of these two different regimes in terms of single versus multiple bonds between pairs of particles and/or patches.

Anisotropic functionalized platelets: percolation, porosity and network properties

“…The interaction between pairs of patches is defined by an attractive or repulsive square-well potential: where p⃑ ij is the patch-to-patch distance, 2 r p is the patch diameter and ε denotes the patch interaction strength. We set r p = 0.05 – as this condition guarantees that each patch can at maximum bond to another patch 52 – and ε = ±1. Patches of the same kind attract each other, while patches of a different kind repel each other, thus an interaction between attractive patches results in a bond, while the interaction between repulsive patches does not.…”

The Physical Chemistry and Chemical Physics (PCCP) Section of the International Journal of Molecular Sciences in Its Publications: The First 300 Thematic Articles in the First 3 Years

“…Articles [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ] can be attributed to the first of the thematic areas indicated in the PCCP Section, and the distribution of these articles into the above categories is presented in Table 2 . As it can be seen, of the four types of articles established by the magazine’s standards ( Reviews , Originals, Communications , Editorials ), only the first two are presented here.…”

“…Articles [ 2 , 3 , 6 ] can also be referred to the biology-medical direction in the Thematic Area 1; the first two of them are devoted to the problem of the so-called molecular recognition of organic compounds, and the third to the specific interaction of peptide molecules in aqueous solutions. The most significant place in this thematic area belongs to works in which mesoporous micro- and nano-spherical particles, and the intermolecular forces associated with them, appear as the object of research [ 12 , 15 , 16 , 17 , 20 ]. These particles are also reviewed in [ 21 ], which provides the latest information on mesoporous silica nanoparticles (MSN), functionalized to target subcellular compartments, with an emphasis on the cytoplasm, mitochondria, and nucleus, which are now widely used as drug carriers due to their unique physical–chemical characteristics.…”