High Quantum Yield Blue Emission from Lead Free Inorganic Antimony Halide Perovskite Colloidal Quantum Dots
High Quantum Yield Blue Emission from Lead Free Inorganic Antimony Halide Perovskite Colloidal Quantum Dots
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DOI：
10.1021/acsnano.7b04683
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发表时间：
2017-09-01
期刊：
影响因子：
17.1
通讯作者：
Song, Haisheng
中科院分区：
文献类型：
--
作者：
Zhang, Jian;Yang, Ying;Song, Haisheng
卤化铅钙钛矿胶体量子点由于其在光电领域的优异性能而受到广泛关注。然而，它们的广泛应用受到有毒铅元素的阻碍，这对环境和消费者都不友好。本文中，我们利用二价铅（Pb 2+）与三价锑（Sb 3+）的异价取代来合成稳定且明亮发光的Cs3Sb2Br9量子点。无铅的，全无机量子点的制备通过修改的配体辅助再沉淀策略。在410 nm处的光致发光量子产率（PLQY）被确定为46%，这是上级于其他报道的卤化物钙钛矿QD的光致发光量子产率。发光增强的机制是由表面组成衍生的量子阱能带结构和它们的大激子结合能。富溴表面和观察到的530 meV激子结合能，提出了保证有效的辐射复合。此外，我们还可以通过阴离子交换反应将无机钙钛矿QD（Cs3Sb2X9）的发射波长从370 nm调谐到560 nm。所开发的具有高PLQY和稳定发射的全无机无铅Sb钙钛矿量子点有望成为高效发射候选者。
Colloidal quantum dots (QDs) of lead halide perovskite have recently received great attention owing to their remarkable performances in optoelectronic applications. However, their wide applications are hindered from toxic lead element, which is not environment- and consumer-friendly. Herein, we utilized heterovalent substitution of divalent lead (Pb2+) with trivalent antimony (Sb3+) to synthesize stable and brightly luminescent Cs3Sb2Br9 QDs. The lead-free, full inorganic QDs were fabricated by a modified ligand-assisted reprecipitation strategy. A photoluminescence quantum yield (PLQY) was determined to be 46% at 410 nm, which was superior to that of other reported halide perovskite QDs. The PL enhancement mechanism was unraveled by surface composition derived quantum-well band structure and their large exciton binding energy. The Br-rich surface and the observed 530 meV exciton binding energy were proposed to guarantee the efficient radiative recombination. In addition, we can also tune the inorganic perovskite QD (Cs3Sb2X9) emission wavelength from 370 to 560 nm via anion exchange reactions. The developed full-inorganic lead-free Sbperovskite QDs with high PLQY and stable emission promise great potential for efficient emission candidates.