Advanced biomimetic approach for crystal growth in nonaqueous media: Morphology and orientation control of pentacosadiynoic acid and applications

In nature, biological macromolecules control the growth of inorganic crystals under mild conditions in aqueous media. Inspired by biomineralization, biomimetic approaches have been studied for growth control of inorganic crystals in aqueous media by using organic molecules and polymers. The approaches were not applied to nonaqueous systems for the development of functional organic materials. Here, we have applied biomimetic approaches to growth control of organic crystals in nonaqueous media. Morphology and orientation of 10,12-pentacosadiynoic acid (PCDA) crystals, a diacetylene derivative, were controlled in organic media with the additive organic polymers and surface-modified substrates. The oriented PCDA ribbons were obtained by an advanced biomimetic approach. After topochemical polymerization, the resultant polydiacetylenes (PDA) ribbons were applied to the thermochromic materials with intercalation of metal ions and the semiconductor layer of an organic field-effect transistor. The present work implies that biomimetic approaches can be applied to morphology and orientation control of organic crystals.