Strong Circularly Polarized Luminescence From Quantum Dots/2D Chiral Perovskites Composites
Strong Circularly Polarized Luminescence From Quantum Dots/2D Chiral Perovskites Composites
复制标题
量子点/二维手性钙钛矿复合材料的强圆偏振发光
DOI：
10.1007/s12274-023-5380-0
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发表时间：
2022
期刊：
影响因子：
9.9
通讯作者：
Kai Wang
中科院分区：
文献类型：
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作者：
Qingqian Wang;Hongmei Zhu;Wei Chen;Junjie Hao;Zhaojin Wang;Jun Tang;Yingguo Yang;Xiao Wei Sun;Dan Wu;Kai Wang
手性钙钛矿（CPs）由于其手性和光电性质的良好结合而受到人们的广泛关注，在圆偏振发光（CPL）领域具有广阔的应用前景，对未来的自旋光电子学具有重要意义。然而，手性钙钛矿中存在一个关键的矛盾，即手性扭曲了晶体结构，导致光致发光（PL）性能差。实现手性和PL之间的平衡是来自手性钙钛矿的强CPL的主要挑战。近年来，二维手性钙钛矿显示出了迷人的手性诱导自旋选择性（CISS）效应，可以在环境条件下作为自旋注入器。在这里，我们提出了一种有效的策略，以实现高CPL活性产生的量子点（QD）通过引入二维手性钙钛矿作为手性源，通过CISS效应提供自旋极化载流子。所合成的量子点/CP复合材料表现出高达9.06 × 10−3的不对称因子（glum）。首次进行了掠入射广角X射线散射（GIWAXS）测量，发现手性来源于大的手性有机阳离子引起的晶格畸变。此外，时间分辨光致发光（TR-PL）测量证实了CPL活性的增强应归因于两个组分之间的电荷传输。这些发现提供了一种在量子点/二维手性钙钛矿异质结中实现CPL的有效方法，这在自旋光电子学应用中可能是有前途的。
Chiral perovskites (CPs) have attracted enormous attentions since they have combined chirality and optoelectrical properties well which is promising in circularly polarized luminescence (CPL) application and of great importance for future spin-optoelectronics. However, there is a key contradiction that in chiral perovskites chirality distorts the crystal structure, leading to poor photoluminescence (PL) properties. Achieving the balance between chirality and PL is a major challenge for strong CPL from chiral perovskites. Differently, two-dimensional (2D) chiral perovskite has shown fascinating chiral induced spin selectivity (CISS) effect which can act as spin injector under ambient conditions. Here, we propose an effective strategy to achieve high CPL activity generated from quantum dots (QDs) by introducing 2D chiral perovskite as a chiral source, providing spin polarized carriers through the CISS effect. The as-synthesized QDs/CP composites exhibit dissymmetry factors (glum) up to 9.06 × 10−3. For the first time, we performed grazing incident wide angle X-ray scattering (GIWAXS) measurements, showing the chirality originates from the distorted lattices caused by the large chiral organic cations. Besides, time-resolved PL (TR-PL) measurements verify the enhanced CPL activity should be attributed to the charge transport between two components. These findings provide a useful method to achieve CPL in QDs/2D chiral perovskite heterojunctions which could be promising in spin-optoelectronics application.