Search

Control of symmetry breaking of materials provides large opportunities to regulate their properties and functions. Herein, we report breaking the symmetry of layered dipeptide crystals by utilizing CO2 to induce the adjacent monomolecular layers to stack from the opposite to the same direction. The role of CO2 is to cover the interlayer interaction sites and force the dipeptides to adsorb at asymmetric positions. Further, the dipeptide crystals exhibit far superior piezoelectricity after symmetry breaking and the piezoelectric voltage generated from the dipeptide‐based generators becomes more than 500 % higher than before. This work reveals a potential route to engineer structures and properties of layered materials and provides a deep insight into the control of non‐covalent interactions. [ABSTRACT FROM AUTHOR]

It is commonly considered that amyloid‐β (Aβ) fibrils are heavily involved in the neurological diseases. Establishing an external model based on the core recognition motif (diphenylalanine, FF) of Aβ would be of significance in understanding the assembly and disassembly of Aβ fibrils in living system. Herein, supramolecular gels with structure transition from amyloid‐like β‐sheet to different supramolecular helices were obtained through the co‐assembly of a N‐fluorenylmethoxycarbonyl‐protected L‐FF (L‐FmocFF) with achiral pyridine derivatives. It is found that the different stacking modes (H‐ or J‐aggregates) of additives and the microenvironment of chiral carbon play vital roles for the selectively chiral transfer or amplification of L‐FmocFF. The dynamic process of helix formation was also captured. This work provides a convenient co‐assembly way to explore the structure basis of Aβ fibrils with a controlled chirality. [ABSTRACT FROM AUTHOR]