Stable and optoelectronic dipeptide assemblies for power harvesting

Publication date: Available online 22 April 2019Source: Materials TodayAuthor(s): Kai Tao, Bin Xue, Qi Li, Wen Hu, Linda J.W. Shimon, Pandeeswar Makam, Mingsu Si, Xuehai Yan, Mingjun Zhang, Yi Cao, Rusen Yang, Junbai Li, Ehud GazitAbstractLow biocompatibility or engineerability of conventional inorganic materials limits their extensive application for power harvesting in biological systems or at bio-machine interfaces. In contrast, intrinsically biocompatible peptide self-assemblies have shown promising potential as a new type of ideal components for eco-friendly optoelectronic energy-harvesting devices. However, the structural instability, weak mechanical strength, and inefficient optical or electrical properties severely impede their extensive application. Here, we demonstrate tryptophan-based aromatic dipeptide supramolecular structures to be direct wide-gap semiconductors. The molecular packings can be effectively modulated by changing the peptide sequence. The extensive and directional hydrogen bonding and aromatic interactions endow the structures with unique rigidity and thermal stability, as well as a wide-spectrum photoluminescence covering nearly the entire visible region, optical waveguiding, temperature/irradiation-dependent conductivity, and the ability to sustain quite high external electric fields. Furthermore, the assemblies display high piezoelectric properties, with a measured open-circuit voltage of up to 1.4 V. Our work provides insights into using aroma...
Source: Materials Today - Category: Materials Science Source Type: research