Perovskite Quantum Dots in Solar Cells

Abstract

Perovskite quantum dots (PQDs) have captured a host of researchers' attention due to their unique properties, which have been introduced to lots of optoelectronics areas, such as light-emitting diodes, lasers, photodetectors, and solar cells. Herein, the authors aim at reviewing the achievements of PQDs applied to solar cells in recent years. The engineering concerning surface ligands, additives, and hybrid composition for PQDSCs is outlined first, followed by analyzing the reasons of undesired performance of PQDSCs. Subsequently, a novel overview that PQDs are utilized to improve the photovoltaic performance of various kinds of solar cells, is provided. Finally, this review is summarized and some challenges and perspectives concerning PQDs are also discussed.

Keywords: high efficiency; perovskite quantum dots; solar cells; structure stability.

Figure 1

Schematic illustration of properties over bulky crystal domains and applications of PQDs in solar cells.

Figure 2

CsPbI₃ PQD properties and optoelectronic devices. a) Normalized UV–visible absorption spectra and photographs of CsPbI₃ PQDs. b) Normalized photoluminescence spectra and photographs under UV illumination of the PQDs. c) X‐ray diffraction (XRD) patterns of PQDs. d) Powder XRD patterns of CsPbI₃ PQDs. e) Current density–voltage (J–V) curves of a device measured in air. Reproduced with permission.^{[ 28 ]} Copyright 2016, American Association for the Advancement of Science.

Figure 3

a) Nuclear magnetic resonance spectra of FAPbI₃ PQDs with increasing number of surface treatment cycles. b) Fourier transform infrared (FTIR) spectra of FAPbI₃ PQDs. c) J–V curves of the devices. d) XRD patterns of FAPbI₃ PQD films. e) Evolution of PCE of devices based on bulk FAPbI₃ and FAPbI₃ PQDs. f) PCE change of the encapsulated device under continuous illumination. Reproduced with permission.^{[ 37 ]} Copyright 2018, Elsevier.

Figure 4

a) Schematic of ligand exchange in CsPbI₃ thin films. b) FTIR spectra of neat OAm (black), OA (blue), and CsPbI₃ PQD films (green, amber, and red). Reproduced with permission.^{[ 75 ]} Copyright 2018, American Chemical Society. c) Schematic of the CsPbI₃ PQD dynamic surface stabilization and the ligand removal process. d) Diagram of the fabrication of devices based on CsPbI₃ PQDs. Reproduced with permission.^{[ 48 ]} Copyright 2020, Wiley‐VCH.

Figure 5

XRD patterns of a) pristine CsPbI₃ and b) 10%‐Zn:CsPbI₃ PQDs with storage for different days. c) Schematic illustration of I defect state (V_I) control by ZnI₂. d) The variation of PLQY values as a function of aged days of the corresponding films. e) Transient photovoltage curves of pristine CsPbI₃ and 10%‐Zn:CsPbI₃ PQDSCs. f) J–V curves of the fabricated devices. Reproduced with permission.^{[ 50 ]} Copyright 2020, Wiley‐VCH.

Figure 6

a) Proposed A‐site cation‐exchange reaction mechanism. b) Schematic illustration of cation exchange in different environments. c) Certificated J–V curve. d) Stability of unencapsulated solar cells fabricated with Cs_0.25FA_0.75PbI₃‐bulk film, Cs_0.25FA_0.75PbI₃‐PQD film, and Cs_0.5FA_0.5PbI₃‐PQD film. Reproduced with permission.^{[ 60 ]} Copyright 2020, Springer Nature.

Figure 7

a) Photoluminescence of Mn‐doped and undoped CsPbCl₃ PQDs and photographs of the sample under UV excitation. Reproduced with permission.^{[ 137 ]} Copyright 2016, American Chemical Society. b) Emission spectra (excited by 365 nm) of glass/FTO, CsPbCl₃/glass/FTO, and CsPbCl₃:0.1Mn/glass/FTO. Reproduced with permission.^{[ 114 ]} Copyright 2017, American Chemical Society. c) Absorption (left) and emission spectra (middle and right) of CsPbCl_1.5Br_1.5 PQDs codoping with various ions. d) J–V curves of the best SSCs coated with different thickness of perovskite film. Reproduced with permission.^{[ 115 ]} Copyright 2017, Wiley‐VCH.

Figure 8

a) Depth‐dependent elemental distribution for films (the pristine MAPbI₃ and the film with 0.25 wt% of PQDs in anti‐solvent). b) Schematic diagram of the uniform distribution of elements across the MAPbI₃ film and self‐assembly of the OA molecules on the surface of the MAPbI₃ film. c) J–V characteristic of the champion device with 0.25 wt% of PQDs in anti‐solvent. d) PCE for the encapsulated device without PQDs and with 0.25 wt% PQDs over time. Reproduced with permission.^{[ 135 ]} Copyright 2019, Elsevier Inc.