北京师范大学化学学院陈玲小组揭示了被细微Ce³⁺杂质掩盖的Ce⁴⁺氟化物内在优越的SHG性能及其有效去除。这一研究成果于2025年2月18日发表在国际顶尖学术期刊《德国应用化学》上。

在此，研究组报道了一系列的氟化铈，包括纯Ce⁴⁺氟化，高性能的Na₂(Ce⁴⁺)F₆；三个混合价态样品（Mix1-3，随Ce³⁺浓度的增加）；和完全还原的纯氟化Ce³⁺ Na_1.5(Ce³⁺)_1.5F₆。其中，Na₂(Ce⁴⁺)F₆表现出4×KDP的SHG响应和4.77eV的宽带隙，是迄今为止所有含Ce材料中最强和最宽的。通过系统的研究，该课题组人员证明了细微的Ce³⁺杂质会显著降低性能。认识到这一点，有意识地控制实验条件，可以保证合成出综合性能优异的纯Na₂(Ce⁴⁺)F₆，具有很大的应用潜力。这项工作不仅强化了Ce⁴⁺在显著提高关键性能方面的关键作用，而且为未来设计更高效、更优越的功能材料提供了宝贵的实验证据和理论支持。

据介绍，由于其独特的电子构型[Xe]4f0， Ce4⁺-化合物在先进的非线性光学材料领域备受期待，但其合成仍然是一个巨大的挑战。

附：英文原文

Title: Unveiling the Intrinsic Superior SHG Performance of Ce⁴⁺ fluoride Masked by Subtle Ce³⁺ Impurity and Its Effective Removal

Author: Meng-Yue Li, Xin Liu, Rui Xi Wang, Li-Ming Wu, Ling Chen, Qi Wu

Issue&Volume: 2025-02-18

Abstract: Owing to its unique electronic configuration [Xe]4f0, Ce⁴⁺-compound is a highly desired in the field of advanced nonlinear optical materials, yet its synthesis remains a great challange. Herein, we report a series of cerium fluorides, including a pure Ce⁴⁺-fluoride, high-performance Na₂(Ce⁴⁺)F₆; three mixed valance state samples, (Mix1–3, with increasing Ce³⁺ concentration); and a fully reduced pure Ce³⁺-fluoride Na_1.5(Ce³⁺)_1.5F₆. In particular, Na₂(Ce⁴⁺)F₆, shows an SHG response (4 × KDP), and a wide band gap (4.77 eV), which are the strongest and widest among all Ce-containing materials to date. With systematic studies, we demonstrate that the subtle Ce³⁺ impurity significantly reduces performance. By being aware of this fact and consciously controlling experimental conditions, we can ensure the synthesis of pure Na₂(Ce⁴⁺)F₆, which exhibits excellent overall performance and shows great potential for future applications. This work not only reinforced the crucial role of Ce⁴⁺ in significantly enhancing the key performance, but also provided invaluable experimental evidence and theoretical support for the future design of more efficient and superior functional materials.

DOI: 10.1002/anie.202502143

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202502143