title: Flower-like supramolecular self-assembly of phosphonic acid appended naphthalene diimide and melamine.
abstract: Diverse supramolecular assemblies ranging from nanometres to micrometers of small aromatic π-conjugated functional molecules have attracted enormous research interest in light of their applications in optoelectronics, chemosensors, nanotechnology, biotechnology and biomedicines. Here we study the mechanism of the formation of a flower-shaped supramolecular structure of phosphonic acid appended naphthalene diimide with melamine. The flower-shaped assembly formation was visualised by scanning electron microscope (SEM) and transmission electron microscopy (TEM) imaging, furthermore, XRD and DLS used to determined mode of aggregation. Characteristically, phosphonic acid-substituted at imide position of NDIs possess two important properties resulting in the formation of controlled flower-like nanostructures: (i) the aromatic core of the NDI which is designed to optimize the dispersive interactions (π-π stacking and van der Waals interactions) between the cores within a construct and (ii) phosphonic acid of NDI interact with malamine through molecular recognition i.e. strong hydrogen-bonding (H-bonding). We believe such arrangements prevent crystallization and favour the directional growth of flower-like nanostructure in 3D fashion. These works demonstrate that complex self-assembly can indeed be attained through hierarchical non-covalent interactions of two components. Furthermore, flower-like structures built from molecular recognition by these molecules indicate their potential in other fields if combined with other chemical entities.
authors.affiliation: RMIT-IICT Research Centre, CSIR-Indian Institute of Chemical Technology, Hyderabad- 500 007, Telangana, India.
authors.forename: Rajesh S
authors.initials: RS
authors.lastname: Bhosale
authors.affiliation: School of Applied Sciences, RMIT University, GPO Box 2476, Melbourne, Vic. 3001, Australia.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Al Kobaisi
authors.affiliation: Polymers and Functional Materials Division, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, Telangana, India.
authors.forename: Sidhanath V
authors.initials: SV
authors.lastname: Bhosale
authors.affiliation: School of Applied Sciences, RMIT University, GPO Box 2476, Melbourne, Vic. 3001, Australia.|Centre for Advanced Materials and Industrial Chemistry (CAMIC), RMIT University, GPO Box 2476, Melbourne, Vic. 3001, Australia.
authors.forename: Suresh
authors.initials: S
authors.lastname: Bhargava
authors.affiliation: School of Applied Sciences, RMIT University, GPO Box 2476, Melbourne, Vic. 3001, Australia.
authors.forename: Sheshanath V
authors.initials: SV
authors.lastname: Bhosale