Quantum Dots Encapsulated by ZrO₂ Enhance the Stability of Perovskite Solar Cells

Abstract

rier recombination [15][16][17][18][19][20] thereby restricting PSCs performance. In addition, water and oxygen in the ambient degrades the performance of PSCs devices through the defects. Therefore, passivation surface defects are one of the methods to improve the stability and device performance of PSCs simply and efficiently. [21][22][23][24] Interface engineering is an effective way to overcome interfacial recombination and improve the performance of PSCs devices. The size and quality of perovskite grain are urgent problems, Lewis acid, [25,26] Lewis base, [20,27] and organic materials [28,29] were developed for passivating the defects through regulating the grain size as the passivation agents. Recently, quantum dots (QDs) passivation has been applied to PSCs to reduce interface defects by filling holes. [30][31][32] QDs were introduced into the PSCs interface engineering as a significant passivation method that can reduce the non-radiative recombination. But the stability of QDs is still an important factor that plagues modification strategies. They are easily decomposed in harsh environments such as humid air. Commonly, polymers, shells, and semiconductors were introduced into the QDs structure to increase the stability and optical properties. Later, the structure of composite QDs compounds was developed. Composite CsPbBr 3 /MoS 2 [33] has been fabricated, corresponding to similar compounds which have also been reported such as CsPbBr 3 /TiO 2 [34,35] and CsPbBr 3 / SiO 2 . [36,37] Zheng et al. [38] construed the CsPbI 3 /Mg x Zn 1-x Te the high-quality, functional nanocomposites. This strategy was proved to improve charge diffusion and separation causing better optical properties. Recently, ZrO 2 has been introduced to composite QDs due to its chemical stability and easy solution processing. Thereby the combination of QDs and ZrO 2 attracts attention ascribed to boosting the performance of the device of composite QDs/ZrO 2 structure. [39] In this study, we use ZrO 2 , as the interface modification layer, to encapsulate the QDs. We obtain the ZrO 2 sol by hydrolysis reaction. [40] Zirconium n-propoxide is hydrolyzed by trace water in n-propanol and toluene to get ZrOH and ZrOC 3 H 7 which interact to form ZrO 2 sol. Acetic acid was added to prevent precipitation. The ZrO 2 sol formed mesh interpenetration structure to encapsulate QDs. The CsPbBr 1.5 I 1.5 /ZrO 2 nanostructure improved the performance and stability of PSCs device with the functions of surface passivation and withstanding harsh environments. The QDs can also modify the morphology and passivating the surface defect. The champion performance of the device based on CsPbBr 1.5 I 1.5 /ZrO 2 achieves a significantly PCE of 21.23%, in contrast to the control device with a PCE In the last several years, perovskite solar cells (PSCs) are faced with big problems in the stability issues, which also occur in the Interface modification materials. Herein, CsPbBr 1.5 I 1.5 quantum dots (QDs) encapsulated in ZrO 2 sol is introduced to improve device stabili...

Strategies to Extend the Lifetime of Perovskite Downconversion Films for Display Applications

“…[ 52 ] Therefore, several groups have attempted to embed the PeNCs in a metal oxide matrix such as SiO 2 , [ 30,49,50 ] TiO 2 , [ 96 ] or ZrO 2 . [ 97 ] However, the method of forming a metal oxide film on the surface of the PeNCs differs according to the material and conditions, so the conditions must be optimized.…”

“…PeNCs surface‐coated with ZrO 2 are more stable than the uncoated PeNCs at room temperature and high humidity (60 ± 10%). [ 97 ]…”

“…[52] Therefore, several groups have attempted to embed the PeNCs in a metal oxide matrix such as SiO 2 , [30,49,50] TiO 2 , [96] or ZrO 2 . [97] However, the method of forming a metal oxide film [49] B) Schematic illustration of formation of PeNC-silica nanocomposites and PLQY stability of the PeNC-silica nanocomposites. [30] C) Synthesis procedure of CsPbBr 3 PeNCs-incorporated PHPS-derived SiO 2 nanocomposites and temperature-dependent PL intensities of CsPbBr 3 (blue open circle) and CsPbBr 3 -SiO 2 composites (green solid triangle).…”

“…Amorphous SiO 2 can be formed on the surface of PeNCs by using the sol-gel method, [101,102] and some authors have attempted to stabilize the surface using Al 2 O 3 , [34] TiO 2 , [96] or ZrO 2 [97] instead of SiO 2 . PeNCs surface-coated with ZrO 2 are more stable than the uncoated PeNCs at room temperature and high humidity (60 ± 10%).…”

“…PeNCs surface-coated with ZrO 2 are more stable than the uncoated PeNCs at room temperature and high humidity (60 ± 10%). [97] PeNCs-polymer composite can be prepared by mixing PeNCs with a reactive resin; however, if the PeNCs-resin and the composite are not compatible, they do not mix with each other. As a result, the particles agglomerate rather than dispersing uniformly in the polymer, so the resulting PeNCs have inferior optical properties.…”