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Hierarchical self-assembly is an effective means of preparing useful materials. However, control over assembly across length scales is a difficult challenge, often confounded by the perceived need to redesign the molecular building blocks when new material properties are needed. Here, we show that we can treat a simple dipeptide building block as a polyelectrolyte and use polymer physics approaches to explain the self-assembly over a wide concentration range. This allows us to determine how entangled the system is and therefore how it might be best processed, enabling us to prepare interesting analogues to threads and webs, as well as films that lose order on heating and "noodles" which change dimensions on heating, showing that we can transfer micellar-level changes to bulk properties all from a single building block.

The self-assembly of small organic molecules can lead to interesting materials such as non-Newtonian fluids and gels. These have potential applications ranging from cell culturing to organic electronics. In this work, a selection of molecules that self-assemble and form low molecular weight gels are studied. In a high throughput photocatalysis experiment, five amino acid functionalised perylene bisimides under a range of variables were tested for the photocatalytic hydrogen evolution reaction from water. The results showed that the formation of 1D nanofibres with a specific molecular packing and surface charge produced optimum rates of H2. Two gelator molecules that formed 1D nanofibres but possessed a different molecular packing were inactive, highlighting the importance and sensitivity of the self-assembly process for any potential application. As well as manipulating the self-assembled structures that form, the ordering of those nanostructures can be controlled through the formation of so called ‘gel noodles’. The influence that nanostructure alignment would have on photocatalysis was of interest but PBIs did not readily form gel noodles. Using a model system of a functionalised dipeptide (1ThNapFF), it was determined that pre-gel solutions containing 1D nanofibres that result in viscous shear-thinning fluids were required to form gel noodles. Highly aligned gel noodles with a uniform size distribution could be prepared by using a spinning technique to subject the pre-gel solution to a stretching and narrowing of diameter (extensional deformation). In the literature, an isoleucine-functionalised PBI (PBI-I) was reported to form highly viscous pre-gel solutions. These solutions were tested. Aligned gel noodles were prepared without the need for the spinning technique. The subtle change in molecular structure resulted in vastly different shear viscosities, facilitating the formation of the gel noodles. Un-aligned gel noodles could be prepared through delayed gelati

The self-assembly of small organic molecules can lead to interesting materials such as non-Newtonian fluids and gels. These have potential applications ranging from cell culturing to organic electronics. In this work, a selection of molecules that self-assemble and form low molecular weight gels are studied. In a high throughput photocatalysis experiment, five amino acid functionalised perylene bisimides under a range of variables were tested for the photocatalytic hydrogen evolution reaction from water. The results showed that the formation of 1D nanofibres with a specific molecular packing and surface charge produced optimum rates of H2. Two gelator molecules that formed 1D nanofibres but possessed a different molecular packing were inactive, highlighting the importance and sensitivity of the self-assembly process for any potential application. As well as manipulating the self-assembled structures that form, the ordering of those nanostructures can be controlled through the formation of so called ‘gel noodles’. The influence that nanostructure alignment would have on photocatalysis was of interest but PBIs did not readily form gel noodles. Using a model system of a functionalised dipeptide (1ThNapFF), it was determined that pre-gel solutions containing 1D nanofibres that result in viscous shear-thinning fluids were required to form gel noodles. Highly aligned gel noodles with a uniform size distribution could be prepared by using a spinning technique to subject the pre-gel solution to a stretching and narrowing of diameter (extensional deformation). In the literature, an isoleucine-functionalised PBI (PBI-I) was reported to form highly viscous pre-gel solutions. These solutions were tested. Aligned gel noodles were prepared without the need for the spinning technique. The subtle change in molecular structure resulted in vastly different shear viscosities, facilitating the formation of the gel noodles. Un-aligned gel noodles could be prepared through delayed gelati

The self-assembly of small organic molecules can lead to interesting materials such as non-Newtonian fluids and gels. These have potential applications ranging from cell culturing to organic electronics. In this work, a selection of molecules that self-assemble and form low molecular weight gels are studied. In a high throughput photocatalysis experiment, five amino acid functionalised perylene bisimides under a range of variables were tested for the photocatalytic hydrogen evolution reaction from water. The results showed that the formation of 1D nanofibres with a specific molecular packing and surface charge produced optimum rates of H2. Two gelator molecules that formed 1D nanofibres but possessed a different molecular packing were inactive, highlighting the importance and sensitivity of the self-assembly process for any potential application. As well as manipulating the self-assembled structures that form, the ordering of those nanostructures can be controlled through the formation of so called ‘gel noodles’. The influence that nanostructure alignment would have on photocatalysis was of interest but PBIs did not readily form gel noodles. Using a model system of a functionalised dipeptide (1ThNapFF), it was determined that pre-gel solutions containing 1D nanofibres that result in viscous shear-thinning fluids were required to form gel noodles. Highly aligned gel noodles with a uniform size distribution could be prepared by using a spinning technique to subject the pre-gel solution to a stretching and narrowing of diameter (extensional deformation). In the literature, an isoleucine-functionalised PBI (PBI-I) was reported to form highly viscous pre-gel solutions. These solutions were tested. Aligned gel noodles were prepared without the need for the spinning technique. The subtle change in molecular structure resulted in vastly different shear viscosities, facilitating the formation of the gel noodles. Un-aligned gel noodles could be prepared through delayed gelati