scispace - formally typeset
Search or ask a question
Journal ArticleDOI

In situ ligand bonding management of CsPbI 3 perovskite quantum dots enables high-performance photovoltaics and red light-emitting diodes

01 Dec 2020-Angewandte Chemie (John Wiley & Sons, Ltd)-Vol. 59, Iss: 49, pp 22230-22237
TL;DR: The L-PHE passivated CsPbI 3 QDs enabled us to realize QD solar cells with an optimal efficiency of 14.62% and red light-emitting diodes (LEDs) with a highest external quantum efficiency (EQE) of 10.21%, respectively, demonstrating the great potential of ligand bonding management in improving the optoelectronic properties of solution-processed perovskite QDs.
Abstract: To fine-tune surface ligands towards high-performance devices, we developed an in situ passivation process for all-inorganic cesium lead iodide (CsPbI3 ) perovskite quantum dots (QDs) by using a bifunctional ligand, L-phenylalanine (L-PHE). Through the addition of this ligand into the precursor solution during synthesis, the in situ treated CsPbI3 QDs display significantly reduced surface states, increased vacancy formation energy, higher photoluminescence quantum yields, and much improved stability. Consequently, the L-PHE passivated CsPbI3 QDs enabled the realization of QD solar cells with an optimal efficiency of 14.62 % and red light-emitting diodes (LEDs) with a highest external quantum efficiency (EQE) of 10.21 %, respectively, demonstrating the great potential of ligand bonding management in improving the optoelectronic properties of solution-processed perovskite QDs.
Citations
More filters
Journal ArticleDOI
TL;DR: In this paper, a hybrid interfacial architecture consisting of CsPbI3 quantum dot/PCBM heterojunction was developed for efficient charge transfer and mechanical adhesion.
Abstract: All-inorganic CsPbI3 perovskite quantum dots have received substantial research interest for photovoltaic applications because of higher efficiency compared to solar cells using other quantum dots materials and the various exciting properties that perovskites have to offer These quantum dot devices also exhibit good mechanical stability amongst various thin-film photovoltaic technologies We demonstrate higher mechanical endurance of quantum dot films compared to bulk thin film and highlight the importance of further research on high-performance and flexible optoelectronic devices using nanoscale grains as an advantage Specifically, we develop a hybrid interfacial architecture consisting of CsPbI3 quantum dot/PCBM heterojunction, enabling an energy cascade for efficient charge transfer and mechanical adhesion The champion CsPbI3 quantum dot solar cell has an efficiency of 151% (stabilized power output of 1461%), which is among the highest report to date Building on this strategy, we further demonstrate a highest efficiency of 123% in flexible quantum dot photovoltaics

166 citations

Journal ArticleDOI
TL;DR: In this article, the degradation mechanisms of inorganic perovskites towards temperature, moisture and oxygen are summarized and discussed, and solutions for tackling these stability issues are reviewed and an outlook on further strategies is provided.
Abstract: Inorganic perovskite based solar cells (PSCs) have been receiving unprecedented attention worldwide in the past several years due to their higher intrinsic stability towards high temperatures and high theoretical power conversion efficiencies. Since a photovoltaic performance of 20.37% has been achieved for inorganic PSCs recently, the operational stability of these devices has become the major bottleneck which impedes their commercialization. The high thermal stability associated with inorganic perovskites comes along with poorer phase stability compared to their hybrid counterparts and therefore needs thorough understanding. Lattice strain and vacancies within the perovskite crystals are found to be the origin of these phase instability issues. This review summarizes the progress in stability research on inorganic perovskites. Specifically, the degradation mechanisms of inorganic perovskites towards temperature, moisture and oxygen are summarized and discussed. Solutions for tackling these stability issues are reviewed and an outlook on further strategies is provided.

142 citations

Journal ArticleDOI
TL;DR: Cubic CsPbI3 perovskite quantum dots (PQDs) with ideal optoelectronic properties are promising materials for solution-processed photovoltaics as mentioned in this paper.
Abstract: Cubic CsPbI3 perovskite quantum dots (PQDs) with ideal optoelectronic properties are promising materials for solution-processed photovoltaics. However, their phase stability suffers from the weakly...

83 citations

Journal ArticleDOI
Yang Bai1, Mengmeng Hao1, Shanshan Ding1, Peng Chen1, Lianzhou Wang1 
TL;DR: In this article, a critical overview focusing on the surface chemistry engineering of perovskite quantum dots (PQDs) including advanced colloidal synthesis, in-situ surface passivation, and solution phase/solid-state ligand exchange is presented, after which their unprecedented achievements in photovoltaics and other optoelectronics are presented.
Abstract: The presence of surface ligands not only plays a key role in keeping the colloidal integrity and non-defective surface of metal halide perovskite quantum dots (PQDs), but also serves as a knob to tune their optoelectronic properties for a variety of exciting applications including solar cells and light-emitting diodes. However, these indispensable surface ligands may also deteriorate the stability and key properties of PQDs due to their highly dynamic binding and insulating nature. To address these issues, a number of innovative surface chemistry engineering approaches have been developed in the past few years. Based on an in-depth fundamental understanding of the surface atomistic structure and surface defect formation mechanism in the tiny nanoparticles, a critical overview focusing on the surface chemistry engineering of PQDs including advanced colloidal synthesis, in-situ surface passivation, and solution-phase/solid-state ligand exchange is presented, after which their unprecedented achievements in photovoltaics and other optoelectronics are presented. The practical hurdles and future directions are critically discussed to inspire more rational design of PQD surface chemistry toward practical applications.

79 citations

References
More filters
Journal ArticleDOI
TL;DR: Two organolead halide perovskite nanocrystals were found to efficiently sensitize TiO(2) for visible-light conversion in photoelectrochemical cells, which exhibit strong band-gap absorptions as semiconductors.
Abstract: Two organolead halide perovskite nanocrystals, CH3NH3PbBr3 and CH3NH3PbI3, were found to efficiently sensitize TiO2 for visible-light conversion in photoelectrochemical cells. When self-assembled on mesoporous TiO2 films, the nanocrystalline perovskites exhibit strong band-gap absorptions as semiconductors. The CH3NH3PbI3-based photocell with spectral sensitivity of up to 800 nm yielded a solar energy conversion efficiency of 3.8%. The CH3NH3PbBr3-based cell showed a high photovoltage of 0.96 V with an external quantum conversion efficiency of 65%.

16,634 citations

Journal ArticleDOI
18 Jul 2013-Nature
TL;DR: A sequential deposition method for the formation of the perovskite pigment within the porous metal oxide film that greatly increases the reproducibility of their performance and allows the fabrication of solid-state mesoscopic solar cells with unprecedented power conversion efficiencies and high stability.
Abstract: Following pioneering work, solution-processable organic-inorganic hybrid perovskites-such as CH3NH3PbX3 (X = Cl, Br, I)-have attracted attention as light-harvesting materials for mesoscopic solar cells. So far, the perovskite pigment has been deposited in a single step onto mesoporous metal oxide films using a mixture of PbX2 and CH3NH3X in a common solvent. However, the uncontrolled precipitation of the perovskite produces large morphological variations, resulting in a wide spread of photovoltaic performance in the resulting devices, which hampers the prospects for practical applications. Here we describe a sequential deposition method for the formation of the perovskite pigment within the porous metal oxide film. PbI2 is first introduced from solution into a nanoporous titanium dioxide film and subsequently transformed into the perovskite by exposing it to a solution of CH3NH3I. We find that the conversion occurs within the nanoporous host as soon as the two components come into contact, permitting much better control over the perovskite morphology than is possible with the previously employed route. Using this technique for the fabrication of solid-state mesoscopic solar cells greatly increases the reproducibility of their performance and allows us to achieve a power conversion efficiency of approximately 15 per cent (measured under standard AM1.5G test conditions on solar zenith angle, solar light intensity and cell temperature). This two-step method should provide new opportunities for the fabrication of solution-processed photovoltaic cells with unprecedented power conversion efficiencies and high stability equal to or even greater than those of today's best thin-film photovoltaic devices.

8,427 citations

Journal ArticleDOI
TL;DR: The compelling combination of enhanced optical properties and chemical robustness makes CsPbX3 nanocrystals appealing for optoelectronic applications, particularly for blue and green spectral regions (410–530 nm), where typical metal chalcogenide-based quantum dots suffer from photodegradation.
Abstract: Metal halides perovskites, such as hybrid organic–inorganic CH3NH3PbI3, are newcomer optoelectronic materials that have attracted enormous attention as solution-deposited absorbing layers in solar cells with power conversion efficiencies reaching 20%. Herein we demonstrate a new avenue for halide perovskites by designing highly luminescent perovskite-based colloidal quantum dot materials. We have synthesized monodisperse colloidal nanocubes (4–15 nm edge lengths) of fully inorganic cesium lead halide perovskites (CsPbX3, X = Cl, Br, and I or mixed halide systems Cl/Br and Br/I) using inexpensive commercial precursors. Through compositional modulations and quantum size-effects, the bandgap energies and emission spectra are readily tunable over the entire visible spectral region of 410–700 nm. The photoluminescence of CsPbX3 nanocrystals is characterized by narrow emission line-widths of 12–42 nm, wide color gamut covering up to 140% of the NTSC color standard, high quantum yields of up to 90%, and radiativ...

6,170 citations

Journal ArticleDOI
TL;DR: A bilayer architecture comprising the key features of mesoscopic and planar structures obtained by a fully solution-based process is reported, providing important progress towards the understanding of the role of solution-processing in the realization of low-cost and highly efficient perovskite solar cells.
Abstract: The performance of solar cells based on organic–inorganic perovskites strongly depends on the device architecture and processing conditions. It is now shown that solvent engineering enables the deposition of very dense perovskite layers on mesoporous titania, leading to photovoltaic devices with a high light-conversion efficiency and no hysteresis.

5,684 citations

Journal ArticleDOI
TL;DR: The demonstration of these novel quantum-dot light-emitting diodes based on all-inorganic perovskite CsPbX3 (X = Cl, Br, I) nanocrystals opens a new avenue toward designing optoelectronic devices, such as displays, photodetectors, solar cells, and lasers.
Abstract: Novel quantum-dot light-emitting diodes based on all-inorganic perovskite CsPbX3 (X = Cl, Br, I) nanocrystals are reported. The well-dispersed, single-crystal quantum dots (QDs) exhibit high quantum yields, and tunable light emission wavelength. The demonstration of these novel perovskite QDs opens a new avenue toward designing optoelectronic devices, such as displays, photodetectors, solar cells, and lasers.

2,311 citations

Related Papers (5)