Loiudice Anna, Saris Seryio, Buonsanti Raffaella
Laboratory of Nanochemistry for Energy (LNCE), Institute of Chemical Sciences and Engineering (ISIC), École Polytechnique Fédérale de Lausanne, Rue de l'Industrie 17, 1950 Sion, Valais, Switzerland.
J Phys Chem Lett. 2020 May 7;11(9):3430-3435. doi: 10.1021/acs.jpclett.0c00820. Epub 2020 Apr 20.
Colloidal semiconductor nanocrystals (NCs) are promising components in various optoelectronic and photocatalytic devices; however, the mechanism of energy transport in these materials remains to be further understood. Here, we investigate the distance dependence of the electronic interactions between CsPbBr nanocubes and CdSe nanoplateles using an alumina (AlO) shell as a spacer. CsPbBr@AlO core@shell NCs are synthesized via colloidal atomic layer deposition (c-ALD), which allows us to fine-tune the oxide thickness and thus the distance between the two NCs. This versatile material platform shows that the electronic interactions between the CsPbBr NCs and the CdSe nanoplatelets can be tuned from electron to energy transfer by increasing the shell thickness, whereas previous studies on the same system had been limited to the former. Considering the applicability of the c-ALD to different NCs, we suggest that metal oxide shell spacers synthesized by this approach can generally be used to study energy-transfer mechanisms at the nanoscale.
胶体半导体纳米晶体（NCs）是各种光电器件和光催化器件中很有前景的组件；然而，这些材料中的能量传输机制仍有待进一步了解。在这里，我们使用氧化铝（AlO）壳作为间隔层，研究了CsPbBr纳米立方体与CdSe纳米片之间电子相互作用的距离依赖性。通过胶体原子层沉积（c-ALD）合成了CsPbBr@AlO核壳纳米晶体，这使我们能够微调氧化物厚度，从而调整两个纳米晶体之间的距离。这个通用的材料平台表明，通过增加壳层厚度，CsPbBr纳米晶体与CdSe纳米片之间的电子相互作用可以从电子转移调整为能量转移，而之前对同一系统的研究仅限于前者。考虑到c-ALD对不同纳米晶体的适用性，我们建议通过这种方法合成的金属氧化物壳间隔层通常可用于研究纳米尺度的能量转移机制。
