Piezoelectric Hydrogen Bonding: Computational Screening for a Design Rationale

Abstract

Organic piezoelectric materials are promising targets in applications such as energy harvesting or mechanical sensors and actuators. In a recent paper (Werling, K. A.; et al. J. Phys. Chem. Lett. 2013, 4, 1365-1370), we have shown that hydrogen bonding gives rise to a significant piezoelectric response. In this article, we aim to find organic hydrogen bonded systems with increased piezo-response by investigating different hydrogen bonding motifs and by tailoring the hydrogen bond strength via functionalization. The largest piezo-coefficient of 23 pm/V is found for the nitrobenzene-aniline dimer. We develop a simple, yet surprisingly accurate rationale to predict piezo-coefficients based on the zero-field compliance matrix and dipole derivatives. This rationale increases the speed of first-principles piezo-coefficient calculations by an order of magnitude. At the same time, it suggests how to understand and further increase the piezo-response. Our rationale also explains the remarkably large piezo-response of 150 pm/V and more for another class of systems, the "molecular springs" (Marvin, C.; et al. J. Phys. Chem. C 2013, 117, 16783-16790.).

The Role of Molecular Polarizability in Designing Organic Piezoelectric Materials

“…Deformation in hydrogen bonds under applied electric field was investigated. As established earlier,, [19] to find such a hydrogen bonded system, a balance between strength of hydrogen bonding and corresponding change in dipole moment with the applied electric field is needed . An attempt was made to establish any short of correlation between piezo‐coefficients and H‐bond energies, molecular polarizability, dipole moment etc.…”

Hydrogen and fluorine co-decorated silicene: A first principles study of piezoelectric properties

“…(14) and f is the applied field. Note that a similar definition is used to predict piezoelectric coefficients in organic 79 Now, we are going to develop a formula to calculate d 33 from energy and e 33 using Taylor expansion. Using a Taylor expansion, we can approximate the thickness deformation, n ¼ ðtÀt 0 Þ t 0 (i.e., an out-of-plane strain that quantifies the amount of thickness change from the equilibrium geometry at zero field), that the system will adopt at an applied field, f, along the z-axis, when our equilibrium geometry at zero field (denoted by (0,0) where n ¼ 0 at zero field) is given.…”

Flexible hybrid eu3+ doped P(VDF-HFP) nanocomposite film possess hypersensitive electronic transitions and piezoelectric throughput

“…This type of bipolar interaction improves the polarization ordering, increases the stability of the molecular chain and leads to a better alignment of instantaneously induced electric dipoles . Conversely, the hydrogen bonding (O − H···F − C) interaction between O–H moieties from a Eu 3+ complex and electronegative fluorine atoms of P(VDF‐HFP) enhances the piezoelectric voltage and it is the key factor of the self‐poling . Here, the dipoles of P(VDF‐HFP) are behaving like self‐polarized along a particular direction that favor a stress induced polarization, and thus an external electrical poling is likely to be avoided …”