有機鐵電渦旋反旋渦疇結構研究
作者:
小柯機器人發布時間:2020/12/19 15:59:23
有機鐵電體因其機械柔韌性、易加工性和低聲阻抗等優點而備受關注。近年來,有機鐵電系統的研究取得了很大的進展,但在有機鐵電體系中,諸如旋渦等拓撲缺陷的研究還相對較少。
該文中,研究人員以[4-氟喹諾酮]ReO4([Q]ReO4)為原料,採用H/F取代的分子設計策略,成功地合成了有機鐵電體[4-氟喹諾酮酸]ReO4([4-F-Q]ReO4)。通過H/F置換,使[Q]ReO4的居裡溫度和自發極化分別從367K和5.83μC/cm2提高到466K和11.37μC/cm2。此外,在機械應力場作用下,在[4-F-Q]ReO4薄膜中出現了三種不同極化方向的帶狀疇,形成了一種風車狀的疇結構,其中穩定地存在著有趣的旋渦-反旋渦拓撲結構。
該項研究為優化有機鐵電體的性質和研究出現的現象提供了一種有效的策略。
附:英文原文
Title: Organic Ferroelectric Vortex–Antivortex Domain Structure
Author: Yuan-Yuan Tang, Yongfa Xie, Yong Ai, Wei-Qiang Liao, Peng-Fei Li, Takayoshi Nakamura, Ren-Gen Xiong
Issue&Volume: December 16, 2020
Abstract: Organic ferroelectrics are attracting tremendous interest because of their mechanical flexibility, ease of fabrication, and low acoustical impedance. Although great advances have been made in recent years, topological defects such as vortices remain relatively unexplored in the organic ferroelectric system. Here, from [quinuclidinium]ReO4 ([Q]ReO4), we applied the molecular design strategy of H/F substitution to successfully synthesize the organic ferroelectric [4-fluoroquinuclidinium]ReO4 ([4-F-Q]ReO4). Through H/F substitution, the Curie temperature and spontaneous polarization are respectively increased from 367 K and 5.83 μC/cm2 in [Q]ReO4 to 466 K and 11.37 μC/cm2 in [4-F-Q]ReO4. Moreover, under mechanical stress fields, three kinds of stripelike domains with various polarization directions emerge to form a windmill-like domain pattern in the thin film of [4-F-Q]ReO4, in which intriguing vortex–antivortex topological configurations can exist stably. This work provides an efficient strategy for optimizing the properties of organic ferroelectrics and exploring emergent phenomena.
DOI: 10.1021/jacs.0c11416
Source: https://pubs.acs.org/doi/10.1021/jacs.0c11416