Down-Shifting and Anti-Reflection Effect of CsPbBr3 Quantum Dots/Multicrystalline Silicon Hybrid Structures for Enhanced Photovoltaic Properties

Abstract

Over the past couple of decades, extensive research has been conducted on silicon (Si) based solar cells, whose power conversion efficiency (PCE) still has limitations because of a mismatched solar spectrum. Recently, a down-shifting effect has provided a new way to improve cell performances by converting ultraviolet (UV) photons to visible light. In this work, caesium lead bromide perovskite quantum dots (CsPbBr3 QDs) are synthesized with a uniform size of 10 nm. Exhibiting strong absorption of near UV light and intense photoluminescence (PL) peak at 515 nm, CsPbBr3 QDs show a potential application of the down-shifting effect. CsPbBr3 QDs/multicrystalline silicon (mc-Si) hybrid structured solar cells are fabricated and systematically studied. Compared with mc-Si solar cells, CsPbBr3 QDs/mc-Si solar cells have obvious improvement in external quantum efficiency (EQE) within the wavelength ranges of both 300 to 500 nm and 700 to 1100 nm, which can be attributed to the down-shifting effect and the anti-reflection property of CsPbBr3 QDs through the formation of CsPbBr3 QDs/mc-Si structures. Furthermore, a detailed discussion of contact resistance and interface defects is provided. As a result, the coated CsPbBr3 QDs are optimized to be two layers and the solar cell exhibits a highest PCE of 14.52%.

Parylene-Sealed Perovskite Nanocrystals Down-Shifting Layer for Luminescent Spectral Matching in Thin Film Photovoltaics

“…In the same wavelength, the absorption of the cell has an average enhancement factor of 5.76 ± 0.01%, in the presence of the thin film down-shifting layer. These results compare very well with those described in the work of Cao et al [ 1 ], on a similar CsPbBr 3 NCs thin film system for down-shifting in microcrystalline silicon solar cells. The paper demonstrated that, at 320 nm, there is an enhancement factor of 27% in the EQE and of 4% in the absorption of the solar cell.…”

“…Silicon based photovoltaic cells have been extensively explored and have become the dominant photovoltaic systems. Silicon is a widely abundant and non-pollutant element, reaching, in crystalline silicon solar cells, very good efficiency, up to 26.8% [ 1 , 2 , 3 ]. Nevertheless, silicon based solar cells, including nanocrystalline silicon solar cells, display low spectral response for high energy photons (in the blue and UV range), which are not converted by the device and raise thermalization issues [ 4 ].…”

ZnO nanostructured materials for emerging solar cell applications

“…198 Recently, the down-shiing effect has been proven to be able to increase the solar cell performance by converting UV light to visible light. 199 Lanthanide down-conversion material, with the ability to absorb UV light and re-emit it in the visible region, was added to the ZnO electron transport layer, so that the re-emitted light matches the absorption energy level of the active layer material. 200 Here, Eu(TTA) 3 phen (ETP) was used as the downconversion material, with PTB7-Th:PC 71 BM as the active layer, resulting in a cell with PCE of 9.22% and 70% higher stability compared to the cell with pristine ZnO.…”

All-inorganic perovskite quantum dots as light-harvesting, interfacial, and light-converting layers toward solar cells

“…The converter can be obtained by simply spin coating AIP QDs on the surface of SCs. For example, Cao et al 162 synthesized CsPbBr 3 QDs with the uniform size of 10 nm, and spin coated the colloidal QDs on the surface of commercial mc-Si SCs to obtain CsPbBr 3 QDs/mc-Si hybrid SCs. Compared with mc-Si SCs, the external quantum efficiency of CsPbBr 3 QDs/mc-Si SCs is signicantly improved in the wavelength range of 300-500 nm and 700-1100 nm, and the maximum PCE of SCs is 14.52%.…”