Control of piezoelectricity in amino acids by supramolecular packing.
Sarah GuerinAimee StapletonDrahomir ChovanRabah MourasMatthew GleesonCian McKeownMohamed Radzi NoorChristophe SilienFernando M F RhenAndrei L KholkinNing LiuTewfik SoulimaneSyed A M TofailDamien ThompsonPublished in: Nature materials (2017)
Piezoelectricity, the linear relationship between stress and induced electrical charge, has attracted recent interest due to its manifestation in biological molecules such as synthetic polypeptides or amino acid crystals, including gamma (γ) glycine. It has also been demonstrated in bone, collagen, elastin and the synthetic bone mineral hydroxyapatite. Piezoelectric coefficients exhibited by these biological materials are generally low, typically in the range of 0.1-10 pm V-1, limiting technological applications. Guided by quantum mechanical calculations we have measured a high shear piezoelectricity (178 pm V-1) in the amino acid crystal beta (β) glycine, which is of similar magnitude to barium titanate or lead zirconate titanate. Our calculations show that the high piezoelectric coefficients originate from an efficient packing of the molecules along certain crystallographic planes and directions. The highest predicted piezoelectric voltage constant for β-glycine crystals is 8 V mN-1, which is an order of magnitude larger than the voltage generated by any currently used ceramic or polymer.
Keyphrases
- amino acid
- molecular dynamics
- particulate matter
- density functional theory
- bone mineral density
- air pollution
- room temperature
- bone regeneration
- molecular dynamics simulations
- water soluble
- monte carlo
- polycyclic aromatic hydrocarbons
- heavy metals
- soft tissue
- bone loss
- high glucose
- postmenopausal women
- body composition
- risk assessment
- heat stress
- ionic liquid
- oxidative stress