Jonathan A Foster

• PhD, MChem
• Fellow at The University of Sheffield

We report the synthesis of a 2D-layered metal-organic framework incorporating weakly interacting chains designed to aid exfoliation of the layers into nanosheets. Dispersion of the nanosheets exposes labile metal-sites which are shown to exchange solvent molecules allowing the nanosheets to act as sensors in suspension.

Here we report a new class of hydrogels formed by polymers that are cross-linked through subcomponent self-assembled metal-organic cages. Selective encapsulation of guest molecules within the cages creates two distinct internal phases within the hydrogel, which allows for contrasting release profiles of related molecules depending on their aptitude...

The incorporation of an N-heterocyclic carbene (NHC) moiety into a self-assembled MII4L6 cage framework required the NHC first to be metallated with gold(I). Bimetallic cages could then be constructed using zinc(II) and cadmium(II) templates, showing weak luminescence. The cages were destroyed by the addition of further gold(I) in the form of AuI(2...

A dynamic-covalent metal-containing polymer was synthesized by the condensation of linear diamine and dialdehyde subcomponents around copper(I) templates in the presence of bidentate phosphine ligands. In solution, the red polymers undergo a sol-gel transition upon heating to form a yellow gel, a process that can be either reversible or irreversibl...

We describe the use of low-molecular-weight supramolecular gels as media for the growth of molecular crystals. Growth of a range of crystals of organic compounds, including pharmaceuticals, was achieved in bis(urea) gels. Low-molecular-weight supramolecular gelators allow access to an unlimited range of solvent systems, in contrast to conventional...

Metal–organic framework nanosheets (MONs) have proved themselves to be useful additives for enhancing the performance of a variety of thin film solar cell devices. However, to date only isolated examples have been reported. In this work we take advantage of the modular structure of MONs in order to resolve the effect of their different structural a...

Peptides are important biomarkers for various diseases, however distinguishing specific amino‐acid sequences using artificial receptors remains a major challenge in biomedical sensing. This study introduces a new approach for creating highly selective recognition surfaces using phage display biopanning against metal–organic nanosheets (MONs). Three...

Ultrasonic liquid exfoliation provides a convenient route for converting layered materials into nanosheets. However, the relationship between the structure and morphology of the bulk materials and the properties of the resulting nanosheets remains poorly understood. In this work, we prepare an isoreticular series of layered metal-organic frameworks...

Metal-organic framework nanosheets (MONs) have proved themselves to be useful additives for enhancing the performance of a variety of thin film solar cell devices. However, to date only isolated examples have been reported. In this work we take advantage of the modular structure of MONs in order to resolve the effect of their different structural a...

Peptides are important biomarkers for a range of diseases, however distinguishing different amino-acid sequences using artificial receptors remains a major challenge in biomedical sensing. Here we present a new approach to creating highly selective recognition surfaces using phage display biopanning against metal-organic nanosheets (MONs) and demon...

Reactive inkjet printing (RIJ) is demonstrated as a new approach to the patterning of surfaces with metal–organic frameworks (MOFs). RIJ is an emerging manufacturing technique that jets solutions of reagents onto a substrate allowing them to react in situ to form the desired material. MOFs have the potential to perform a variety of useful sensing,...

Optimizing the orientation, crystallinity, and domain size of components within organic photovoltaic (OPV) devices is key to maximizing their performance. Here a broadly applicable approach for enhancing the morphology of bulk heterojunction OPV devices using metal–organic nanosheets (MONs) as additives is demonstrated. It is shown that addition of...

Metal‐organic framework nanosheets (MONs) have recently emerged as a distinct class of 2D materials with programmable structures that make them useful in diverse applications. In this review, the breadth of applications that have so far been investigated are surveyed, thanks to the distinct combination of properties afforded by MONs. How: 1) The hi...

Metal-organic framework nanosheets (MONs) are attracting increasing attention as a diverse class of two-dimensional materials derived from metal-organic frameworks (MOFs). The principles behind the design of layered MOFs that can readily be exfoliated to form nanosheets, however, remain poorly understood. Here we systematically investigate an isore...

We report the synthesis of a bis(urea) gelator designed to specifically mimic the chemical structure of the highly polymorphic drug substance ROY. Crystallization of ROY from toluene gels of this gelator results in the formation of the metastable red form instead of the thermodynamic yellow polymorph. In contrast, all other gels and solution contro...

Supramolecular gelators with different fibre morphologies have been used as templates to form mesoporous covalent polymers with different pore shapes. Two bis-urea derived gelators functionalised with different amino-acid groups form gels in 1 : 1 methyl methacrylate : ethylene glycol dimethacrylate (MMA: EGDMA) mixtures with either ribbon-like or...

Blending different low molecular weight gelators (LMWGs) provides a convenient route to tune the properties of a gel and incorporate functionalities such as fluorescence. Blending a series of gelators having a common bis-urea motif, and functionalised with different amino acid-derived end-groups and differing length alkylene spacers is reported. Fl...

Supramolecular gels are topical soft materials involving the reversible formation of fibrous aggregates using non-covalent interactions. There is significant interest in controlling the properties of such materials by the formation of multicomponent systems, which exhibit non-additive properties emerging from interaction of the components. The use...

A series of chiral bis(urea) compounds based on oligomethylene spacers with S-phenylethyl end groups have been investigated as low molecular weight gelators. The series shows gelation of a variety of liquids and their structural, morphological and rheological properties are reported. The bis(urea) compounds also act as supramolecular hosts for anio...

Hydrogen bonding interactions with the π-system of thiocarbonyls are evident in the X-ray crystal structures of a range of thiourea derivatives and from an analysis of the CSD.

A simple triethoxysilane appended bis(urea) low molecular weight gelator (LMWG) affords strong gels in organic solvents that are susceptible to fine tuning by anion binding, while the gel structure can be rigidified into a porous hybrid polymer material by hydrolysis of the triethoxysilane end groups.

Endowing supramolecular gelators with cavities opens up a number of opportunities not possible with other gel systems. The well-established host-guest chemistry of cavitands can be utilized to build up and break down gel structures, introduce responsive functionalities, or enhance selectivity in applications such as catalysis and extraction. Cavity...

Der Einsatz supramolekularer Gelatoren mit Hohlräumen eröffnet eine Reihe von Möglichkeiten, die bei anderen Gelsystemen nicht zur Verfügung stehen. Mit der bekannten Wirt-Gast-Chemie von Cavitanden können Gelstrukturen auf- und abgebaut, reaktionsfähige Funktionalitäten eingeführt und die Selektivität bei Anwendungen wie Katalyse oder Extraktion p...