Mn-inlaid antiphase boundaries in perovskite structure

• Published in: Nature communications Vol. 15; no. 1; pp. 6735 - 9
• Main Authors: Li, Chao, Wang, Lingyan, Xu, Liqiang, Ren, Xuerong, Yao, Fangzhou, Lu, Jiangbo, Wang, Dong, Liang, Zhongshuai, Huang, Ping, Wu, Shengqiang, Jing, Hongmei, Zhang, Yijun, Dong, Guohua, Liu, Haixia, Ma, Chuansheng, Lyu, Yinong, Wei, Xiaoyong, Ren, Wei, Wang, Ke, Ye, Zuo-Guang, Chen, Feng
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 07.08.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 147/137; 639/301/119/996; 639/301/930/328/2082; Antiphase boundaries; Atomic structure; Boundaries; Chemical composition; Crystal structure; Design factors; Design optimization; Electric fields; Ferroelectric materials; Ferroelectricity; Humanities and Social Sciences; Hysteresis loops; Lead; Metal ions; multidisciplinary; Perovskite structure; Perovskites; Polarization; Pulsed laser deposition; Pulsed lasers; Science; Science (multidisciplinary); Thin films; Vaporization; Volatilization
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-51024-2

Improvements in the polarization of environmentally-friendly perovskite ferroelectrics have proved to be a challenging task in order to replace the toxic Pb-based counterparts. In contrast to common methods by complex chemical composition designs, we have formed Mn-inlaid antiphase boundaries in Mn-doped (K,Na)NbO 3 thin films using pulsed laser deposition method. Here, we observed that mono- or bi-atomic layer of Mn has been identified to inlay along the antiphase boundaries to balance the charges originated from the deficiency of alkali ions and to induce the strain in the KNN films. Thus, rectangular saturated polarization-electric field hysteresis loops have been achieved, with a significantly improved twice remanent polarization of 114 μC/cm 2 with an applied electric field of 606 kV/cm, which can be comparable to that of the typical Pb-based thin films. Moreover, we directly see the Mn occupation at the A-site of KNN perovskite structure using atomic-scale microstructure and composition analysis. The Mn-inlaid antiphase boundary can further enrich the understanding of perovskite crystal structure and give more possibilities for the design and optimization of perovskite materials. The volatilization of alkaline ions is a main factor to degrade the performances of KNN films. Here, the authors utilized the volatilization and incorporation of Mn to construct periodical Mn-inlaid antiphase boundaries in KNN matrix, leading to an improvement of ferroelectric properties.