Salvato in:
| Autori principali: | , , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2025
|
| Soggetti: | |
| Accesso online: | https://arxiv.org/abs/2507.15687 |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866918100083933184 |
|---|---|
| author | Li, Denan Ni, Haofei Zhang, Yi Liu, Shi |
| author_facet | Li, Denan Ni, Haofei Zhang, Yi Liu, Shi |
| contents | Organic--inorganic hybrid perovskites with giant piezoelectric responses, exemplified by TMCM-CdCl$_3$, represent a promising platform for flexible and environmentally friendly electromechanical materials. However, the microscopic origin of such exceptional performance in this weakly polar system has remained elusive. Here, using deep-learning-assisted large-scale molecular dynamics simulations, we resolve this paradox by reproducing the experimentally measured piezoelectric coefficient $d_{33} \approx 220$~pC/N, and demonstrating that the giant response arises from the collective contribution of multiple intrinsic components, particularly the shear component $d_{15}$. This effect does not stem from conventional polarization rotation or phase switching, but instead originates from stochastic 120$^\circ$ in-plane rotational hopping of a small fraction of organic cations. This discrete hopping mechanism is governed by the local C$_3$-symmetric halogen-bonding network between the host framework and the guest cation. The Arrhenius-type temperature dependence of $d_{15}$ further confirms the role of thermally activated dipole hopping. This work provides a clear pathway to enhance piezoelectric performance of hybrid materials through rational engineering of host--guest interactions. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2507_15687 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Giant Reversible Piezoelectricity from Symmetry-Governed Stochastic Dipole Hopping Li, Denan Ni, Haofei Zhang, Yi Liu, Shi Materials Science Organic--inorganic hybrid perovskites with giant piezoelectric responses, exemplified by TMCM-CdCl$_3$, represent a promising platform for flexible and environmentally friendly electromechanical materials. However, the microscopic origin of such exceptional performance in this weakly polar system has remained elusive. Here, using deep-learning-assisted large-scale molecular dynamics simulations, we resolve this paradox by reproducing the experimentally measured piezoelectric coefficient $d_{33} \approx 220$~pC/N, and demonstrating that the giant response arises from the collective contribution of multiple intrinsic components, particularly the shear component $d_{15}$. This effect does not stem from conventional polarization rotation or phase switching, but instead originates from stochastic 120$^\circ$ in-plane rotational hopping of a small fraction of organic cations. This discrete hopping mechanism is governed by the local C$_3$-symmetric halogen-bonding network between the host framework and the guest cation. The Arrhenius-type temperature dependence of $d_{15}$ further confirms the role of thermally activated dipole hopping. This work provides a clear pathway to enhance piezoelectric performance of hybrid materials through rational engineering of host--guest interactions. |
| title | Giant Reversible Piezoelectricity from Symmetry-Governed Stochastic Dipole Hopping |
| topic | Materials Science |
| url | https://arxiv.org/abs/2507.15687 |