Kahraman Abdullah, Socie Etienne, Nazari Maryam, Kazazis Dimitrios, Buldu-Akturk Merve, Kabanova Victoria, Biasin Elisa, Smolentsev Grigory, Grolimund Daniel, Erdem Emre, Moser Jacques E, Cannizzo Andrea, Bacellar Camila, Milne Christopher
Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
École polytechnique fédérale de Lausanne (EPFL), Rte Cantonale, 1015 Lausanne, Switzerland.
J Phys Chem Lett. 2024 Feb 15;15(6):1755-1764. doi: 10.1021/acs.jpclett.3c03519. Epub 2024 Feb 7.
The synthesis and control of properties of p-type ZnO is crucial for a variety of optoelectronic and spintronic applications; however, it remains challenging due to the control of intrinsic midgap (defect) states. In this study, we demonstrate a synthetic route to yield colloidal ZnO quantum dots (QD) via an enhanced sol-gel process that effectively eliminates the residual intermediate reaction molecules, which would otherwise weaken the excitonic emission. This process supports the creation of ZnO with p-type properties or compensation of inherited n-type defects, primarily due to zinc vacancies under oxygen-rich conditions. The in-depth analysis of carrier recombination in the midgap across several time scales reveals microsecond carrier lifetimes at room temperature which are expected to occur via zinc vacancy defects, supporting the promoted p-type character of the synthesized ZnO QDs.
p型氧化锌的合成及其性能控制对于各种光电子和自旋电子应用至关重要；然而，由于本征带隙中间（缺陷）态的控制，这仍然具有挑战性。在本研究中，我们展示了一种通过增强溶胶-凝胶工艺制备胶体氧化锌量子点（QD）的合成路线，该工艺有效消除了残留的中间反应分子，否则这些分子会削弱激子发射。此过程有助于生成具有p型性质的氧化锌或补偿继承的n型缺陷，这主要归因于富氧条件下的锌空位。对跨越几个时间尺度的带隙中间载流子复合的深入分析揭示了室温下微秒级的载流子寿命，预计这是通过锌空位缺陷发生的，这支持了合成的氧化锌量子点所具有的增强的p型特性。
