CsPbCl3 Perovskite Nanocrystals Research Articles

Efficient Large-Area Quantum Cutting Photoconversion Films for Silicon Solar Cells on Photovoltaic Glass Using Knife Coating.

Yb3+ doped perovskite nanocrystals (PNCs) serve as efficient photoconverters, exhibiting quantum cutting emission at ∼980 nm, which aligns precisely with the optimal response region of silicon solar cells (SSCs). However, severe nonradiative recombination caused by defects in the crystal lattice and film boundaries, along with limitations in small-scale film preparation, restricts their commercial application. Here, we used Ru3+ to mitigate lattice defects in CsPbCl3 PNCs and adjusted the quantum cutting luminescence, achieving a 175% photoluminescence quantum yield (PLQY). The results show that Ru3+ ions enter the perovskite lattice, fill lead vacancies, and passivate the lattice defects. Furthermore, cysteine effectively eliminates surface defects in PNCs by forming Pb-S bonds, resulting in films with a remarkable 117% PLQY, demonstrating strong photoconversion capabilities. Uniformly knife-coated on 20 × 20 cm2 photovoltaic glass, these films increased SSC efficiency from 21.45% to 23.15%. This study showcases a cost-effective photoconverter and a scalable coating method to boost the photovoltaic efficiency of large-area SSCs.

A Comprehensive Review on Mechanisms and Applications of Rare‐Earth Based Perovskite Nanocrystals†

Comprehensive SummaryRare earth (RE) ions, with abundant 4f energy level and unique electronic arrangement, are considered as substitutes for Pb2+ in perovskite nanocrystals (PNCs), allowing for partial or complete replacement of lead and minimizing environmental impact. This review provides a comprehensive overview of the characteristics of RE‐doped PNCs, including up‐conversion luminescence, down‐conversion luminescence, and quantum confinement effects, etc. Additionally, RE doping has been found to effectively suppress defect formation, reduce nonradiative recombination, enhance photoluminescence quantum yield (PLQY), and even allow for controlling over the morphology of the nanocrystals. The review also highlights the recent advancements in lead‐free RE‐based perovskites, especially in the case of Eu‐based perovskites (CsEuBr3 and CsEuCl3). Furthermore, it briefly introduces the applications of PNCs in various fields, such as perovskite solar cells (PSCs), luminescent solar concentrators (LSCs), photodetectors (PDs), and light‐emitting diodes (LEDs). A systematic discussion on the luminescence mechanisms of RE‐doped PNCs and lead‐free RE‐based perovskites is provided, along with an outlook on future research directions. The ultimate goal of this review is to provide guidance for the development of RE‐based perovskite optoelectronic devices. Key ScientistsIn 2015, Kovalenko et al. pioneered the synthesis of lead‐based perovskite nanocrystals using the thermal injection method. Concurrently, Zhong et al. introduced the ligand‐assisted reprecipitation method. These methods have become the predominant approaches for fabricating lead‐based perovskite nanocrystals. In 2017, Song et al. successfully incorporated various rare earth ions (Ce3+, Sm3+, Eu3+, Tb3+, Dy3+, Er3+, and Yb3+) into CsPbCl3 perovskite nanocrystals. They also observed the quantum cutting effect induced by defect states, facilitated by the doping of Yb3+. Gamelin et al. subsequently proposed that CsPbCl3:Yb3+ nanocrystals exhibit quantum cutting effects due to the introduction of charge‐compensating defects (VPb), resulting in the formation of Yb3+‐VPb‐Yb3+ defect complexes with shallow defect levels. In 2020, Zhang et al. successfully doped Nd3+ into CsPbBr3, yielding blue luminescent nanocrystals with a central wavelength of 459 nm and up to 90% photo‐luminescence quantum yield (PLQY). In the same year, Yang et al. achieved the synthesis of pure phase CsEuCl3 perovskite nanocrystals for the first time. In 2022, Paik et al. synthesized Cs3LnCl6 (Ln = Y, Ce, Gd, Er, Tm, Yb, Eu, Tb) nanocrystals using the thermal injection method. In 2023, Zhang et al. successfully introduced Ni2+ doping into CsEuCl3, enhancing the PLQY of CsEuCl3 nanocrystals from 5% to 19.7%. This review focuses on the development history of perovskite nanocrystals, including rare earth‐doped lead‐based perovskite nanocrystals and rare earth‐based lead‐free perovskite nanocrystals, as well as their applications.

2,2′-Bipyridine-4,4′-dicarboxylic Acid-Mediated Surface Engineering of Mn-Doped CsPbCl3 Perovskite Nanocrystals

The metal doping strategy reduces the defect/trap states and improves the stability of CsPbCl3, which is beneficial for optoelectronic applications. Mn doping in CsPbCl3 perovskite nanocrystals (PNCs) has shown an improved photoluminescence quantum yield (PLQY) and stability; however, the emission in these PNCs is limited to trap-mediated energy transfer. Herein, we have demonstrated for the first time improvement in the energy transfer properties, relative PLQY, and stability of Mn-doped CsPbCl3 PNCs by post-synthesis surface passivation with a small organic molecule, 2,2′-bipyridine-4,4′-dicarboxylic acid (BPY). BPY is used as an efficient passivating additive, which reduces surface defects in Mn-doped CsPbCl3 via the electrostatic interactions of carboxyl groups and pyridine nitrogen with less coordinated Pb atoms; hence, the improvement happened in the energy transfers from CsPbCl3 to Mn2+ dopants and the relative PLQY. The relative PLQY of the Mn-doped CsPbCl3 PNCs increased from 23 to 70% after post-synthesis BPY treatment. The Mn-doped CsPbCl3 PNCs were characterized before and after BPY passivation using various characterization techniques. Thermal and photostability studies under ambient conditions and UV light irradiation showed that the BPY-passivated Mn-doped CsPbCl3 PNCs are more stable than the unpassivated ones.

The Mn-Doped CsPbCl3 Perovskite Nanocrystals as a Photoluminescent Probe for Copper Ions Detection

Trace detection of toxic heavy metal ions is a hot topic in the sensing research area, especially in the organic phase using inorganic fluorescent colloidal nanocrystals. We report Mn-doped CsPbCl3 perovskite nanocrystals (PNCs), which were synthesized via the hot-injection method, as a fluorescent probe for the detection of copper ions in hexane. The introduction of Mn altered the emission peak, and lower the toxicity of the probe material. The photoluminescence (PL) intensity of Mn-doped CsPbCl3 PNCs is significantly quenched after contact with the [Formula: see text] solution. The mechanism of Cu quenching is electron transfer, which is experimentally proved by analyzing the PL spectrum, absorption spectrum and PL decay lifetime. The sensor in solution shape and solid shape is both prepared and their detection range from 10 nM to 500 [Formula: see text]M. The limit of detection in a low concentration area reaches 10 nM, showing great potential in sensing applications. This work expands the wavelength area of the [Formula: see text] detection probe by perovskite nanocrystals, and also improves the properties of probe material in optical performance, low toxicity, and stability.

Polar-Solvent-Free Sonochemical Synthesis of Mn(II)-Doped CsPbCl3 Perovskite Nanocrystals for Dual-Color Emission

We present a facile, one-step, polar-solvent-free sonochemical synthesis of a series of Mn-doped CsPbCl3 perovskite nanocrystals (PNCs) by varying the Pb-to-Mn ratio, after which their structure, morphology, and temperature-dependent photoluminescence (PL) properties are investigated. The partial substitution of Pb2+ with Mn2+ in CsPbCl3 PNCs caused lattice contraction without affecting the morphology and structure. All Mn-doped PNCs exhibited dual-wavelength PL profiles, with a weak violet band at around 410 nm attributed to band-edge exciton and a strong orange band at around 596 nm attributed to Mn2+:4T1→6A1 transition, benefited by the exciton-to-Mn2+ energy transfer. Furthermore, Mn doping increased the PL quantum yield (PLQY) from 5.1% in CsPbCl3 to 41.14% for 11.8% Mn-doped PNCs as well as decay lifetimes from nanoseconds to milliseconds (long-lived emissive states). Owing to the thermally assisted transition from the exciton to 4T1 energy level of Mn2+, the temperature-dependent steady-state PL and time-resolved PL spectra of exciton and Mn2+ in Mn-doped CsPbCl3 PNCs displayed unusual and contradictory trends. The ultrasonication synthesized Mn-doped PNCs exhibited superior long-term stability, retaining 62% (@ RH 75%) of the initial PL without requiring additional encapsulation. To evaluate the suitable application of Mn-doped CsPbCl3 PNCs in the white light-emitting diode (w-LED) as a display system, we built a prototype w-LED using blue-, green-, and orange-emitting CsPb(Cl0.5/Br0.5)3, CsPbBr3, and Mn-doped CsPbCl3-coated glass slices onto a 20 mA UV LED chip. The constructed prototype w-LED generated bright white light, achieving a luminous efficiency of 76.3 lm/W, color rendering index of 81.4, R9 of 80.1, and a wide color gamut of 101.78% NTSC and 76% BT-2020, demonstrating its promising application in w-LEDs.

Synergetic effects of the co-doping transition metal ions and the silica-shell coating for enhancing the photoluminescence and stability of Mn: CsPbCl3 nanocrystals and their application

Doping Mn2+ ions into cesium lead halide CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (PNCs) has been proven to be an effective strategy to reduce the Pb2+ content. However, excessive Mn2+ ions may form the Mn–Mn dimers in PNCs, leading to concentration quenching effects and low photoluminescence quantum yields (PLQYs). Herein, secondary metal ions (Ni2+, Cu2+, Zn2+) were introduced to substitute Pb2+ ions as co-doped (Mn, M):CsPbCl3 PNCs (M = Ni, Cu, Zn), which were prepared by a facile method under ambient conditions, aiming for positively passivating the surface defects and improving the Mn2+ emission. Also, to protect the co-doped (Mn, M):CsPbCl3 PNCs from moisture damage, we performed silica encapsulation, which further passivated surface defects due to the effective hydrolysis of silane. The evolution of optical properties and stabilities of three series of (Mn, M):CsPbCl3 PNCs was compared. The PLQYs of co-doped (Mn, M):CsPbCl3 PNCs were larger than those of single-doped Mn: CsPbCl3 PNCs, especially for (Mn, Ni):CsPbCl3 and (Mn, Cu):CsPbCl3, which can reach nearly 30%. The PLQYs of (Mn, Ni):CsPbCl3 and (Mn, Zn):CsPbCl3 PNCs decreased dramatically during the encapsulation process, while the PLQY values of (Mn, Cu):CsPbCl3 remained 30% even after the same treatment process. Consequently, the prototypes of white light-emitting devices (WLEDs) were successfully fabricated based on orange-red (Mn, Ni):CsPbCl3@SiO2 and (Mn, Zn):CsPbCl3@SiO2 composites. The synergetic effects of co-doping transition metal ions and silica-shell coating on improving optical properties and stabilities were investigated. It has potential for a wide range of applications in the field of solid-state light emission.

Efficient single-component white light emitting diodes enabled by lanthanide ions doped lead halide perovskites via controlling Förster energy transfer and specific defect clearance

Currently, a major challenge for metal-halide perovskite light emitting diodes (LEDs) is to achieve stable and efficient white light emission due to halide ion segregation. Herein, we report a promising method to fabricate white perovskite LEDs using lanthanide (Ln3+) ions doped CsPbCl3 perovskite nanocrystals (PeNCs). First, K+ ions are doped into the lattice to tune the perovskite bandgap by partially substituting Cs+ ions, which are well matched to the transition energy of some Ln3+ ions from the ground state to the excited state, thereby greatly improving the Förster energy transfer efficiency from excitons to Ln3+ ions. Then, creatine phosphate (CP), a phospholipid widely found in organisms, serves as a tightly binding surface-capping multi-functional ligand which regulates the film formation and enhances the optical and electrical properties of PeNC film. Consequently, the Eu3+ doped PeNCs based-white LEDs show a peak luminance of 1678 cd m-2 and a maximum external quantum efficiency (EQE) of 5.4%, demonstrating excellent performance among existing white PeNC LEDs from a single chip. Furthermore, the method of bandgap modulation and the defect passivation were generalized to other Ln3+ ions doped perovskite LEDs and successfully obtained improved electroluminescence (EL). This work demonstrates the comprehensive and universal strategies in the realization of highly efficient and stable white LEDs via single-component Ln3+ ions doped PeNCs, which provides an optimal solution for the development of low-cost and simple white perovskite LEDs.

Halide perovskites as disposable epitaxial templates for the phase-selective synthesis of lead sulfochloride nanocrystals

Colloidal chemistry grants access to a wealth of materials through simple and mild reactions. However, even few elements can combine in a variety of stoichiometries and structures, potentially resulting in impurities or even wrong products. Similar issues have been long addressed in organic chemistry by using reaction-directing groups, that are added to a substrate to promote a specific product and are later removed. Inspired by such approach, we demonstrate the use of CsPbCl3 perovskite nanocrystals to drive the phase-selective synthesis of two yet unexplored lead sulfochlorides: Pb3S2Cl2 and Pb4S3Cl2. When homogeneously nucleated in solution, lead sulfochlorides form Pb3S2Cl2 nanocrystals. Conversely, the presence of CsPbCl3 triggers the formation of Pb4S3Cl2/CsPbCl3 epitaxial heterostructures. The phase selectivity is guaranteed by the continuity of the cationic subnetwork across the interface, a condition not met in a hypothetical Pb3S2Cl2/CsPbCl3 heterostructure. The perovskite domain is then etched, delivering phase-pure Pb4S3Cl2 nanocrystals that could not be synthesized directly.

Mn‐Doped Perovskite Nanocrystals for Photocatalytic CO2 Reduction: Insight into the Role of the Charge Carriers with Prolonged Lifetime

As an emerged photocatalyst, perovskites have attracted enormous interest in photocatalysis due to their excellent photoelectronic properties. However, most of the photoexcited electron–hole pairs recombine together before they reach the surface of perovskite for photocatalysis. The undesired charge recombination would compete with the surface photocatalytic reaction. Hence, the regulation of charge carriers is essential for improving the photocatalytic performance of perovskites. Herein, the charge transfer dynamics by doping Mn2+ in CsPbCl3 perovskite nanocrystals (NCs) is manipulated and the role of the charge carriers with a prolonged lifetime in photocatalysis is investigated. The photogenerated charge carriers with a prolonged lifetime at both Mn2+ dopants and conduction band (CB) endow Mn:CsPbCl3 NCs with an enhanced photocatalytic activity toward CO2 reduction. The doping strategy provides us with a powerful tool to regulate the charge transfer dynamics in perovskite NCs for photocatalysis. It is believed that the long‐lived charge carriers in perovskite NCs have great potential in promoting charge separation and suppressing charge recombination in solar‐to‐fuel conversions.

Halogen‐content‐dependent photoluminescence of Mn2+‐doped CsPbCl3 nanocrystals

AbstractThe thermodynamically viable halogen vacancy defects in CsPbCl3 perovskite nanocrystals (NCs) are considered the main factor in weakening their optical quality. However, their separate impact on the dopant emission in Mn2+‐doped CsPbCl3 perovskite NCs is still under exploration owing to the absence of comparable samples. Herein, a series of Mn2+‐doped CsPbCl3 samples were synthesized with different oleylamine‐Cl (OAm‐Cl) contents based on a halogen‐hot‐injection strategy. It is found that the Mn2+ concentration of as‐prepared samples fixed at 0.65%, and the Mn2+ photoluminescence (PL) also exhibited an OAm‐Cl content‐independent lifetime of ∼ 1.78 ms, implying the efficient and identical luminescence of isolated Mn2+ ion in all samples. In contrast, the excitonic and Mn2+ PL intensities of the NCs are strong related to the amount of OAm‐Cl, which are attributed to the coordination effect of the suppressed excitonic nonradiative recombination owing to the passivation of chloride vacancies and the enhanced energy transfer from the host exciton to Mn2+ ions in the samples with sufficient OAm‐Cl contents. The temperature‐dependent of Mn2+ PL disclosed an initial increase and was followed by a decrease with increasing temperature for the samples with relatively higher OAm‐Cl contents, while it monotonously decreases for the sample with lower OAm‐Cl content of 0.4 mL. The different PL intensity change trend results from the effective passivation of chloride vacancies by extra OAm‐Cl. Above results present here will help clarify the underlying influence mechanism of halogen vacancy on the PL properties of Mn2+‐doped perovskite NCs, which is essential for targeted modulation of their optical properties.

Promoting the doping efficiency and photoluminescence quantum yield of Mn-doped perovskite nanocrystals via two-step hot-injection.

Manganese-doped perovskite nanocrystals (NCs) have been synthesized by a novel two-step hot-injection strategy with an unprecedented Mn doping efficiency of 48.5%, bright orange emission under ultraviolet light and X-ray excitation and a photoluminescence quantum yield of 84.4%, making them excellent luminescent materials.

Revealing the effect of electrochemical switching and energy transfer on the electrochemiluminescence of Mn-doped CsPbCl3 nanocrystals

The electrochemical behavior and consequent luminescence properties of Mn-doped CsPbCl3 perovskite (Mn:CsPbCl3) nanocrystals (NCs) were investigated by cyclic voltammetry (CV) and electrochemiluminescence (ECL) measurements. Mn:CsPbCl3 NCs could be electrochemically injected with electrons or holes at different potentials to produce ECL through both annihilation and coreactant routes. Importantly, it has been found that the ECL involving the coreactant could originate from two pathways: energy recombination at the surface, and energy transfer from the excited CsPbCl3 host to the dopant center, producing emission via Mn d-d transition, which is different from the photoluminescence (PL) of Mn:CsPbCl3 NCs alone, which contains dual emissions from both the host and the dopant.

Ytterbium-Doped CsPbCl3 Quantum Cutters for Near-Infrared Light-Emitting Diodes

Exploring highly efficient near-infrared (NIR) emitting materials is desirable for the advancement of next-generation smart NIR light sources. Different from most reported Cr3+-doped emitters with far-red emissions, Yb3+-activated phosphors are expected to yield pure NIR (∼1000 nm) light. Herein, a new hot-injection route using all metal-oleate salts to fabricate Yb3+-doped CsPbCl3 perovskite nanocrystals (PeNCs) is reported for the first time, which produce PeNC-sensitized Yb3+ NIR emission with photoluminescence quantum yields (PLQYs) higher than 100%. With the help of temperature-dependent PL spectra, femtosecond transient absorption spectra, and time-resolved PL spectra, it is evidenced that the in situ produced intrinsic shallow trap states in a CsPbCl3 host play a key role in facilitating the picosecond nonradiative cooperative energy transfer from PeNCs to two Yb3+ dopants simultaneously. Using the optimized Yb3+:CsPbCl3 quantum cutters, a phosphor-converted NIR light-emitting diode (pc-NIR-LED) is fabricated, exhibiting an external quantum efficiency of 2%@28 mA, a high NIR output irradiance of 112 mW/cm2@400 mA, and excellent long-term stability. Finally, the designed pc-NIR-LED is demonstrated to have great potential as an invisible night-vision light source.

Pressure-Engineered Optical and Charge Transport Properties of Mn2+/Cu2+ Codoped CsPbCl3 Perovskite Nanocrystals via Structural Progression.

In this work, compared with the corresponding pure CsPbCl3 nanocrystals (NCs) and Mn2+-doped CsPbCl3 NCs, Mn2+/Cu2+-codoped CsPbCl3 NCs exhibited improved photoluminescence (PL) and photoluminescence quantum yields (PL QYs) (57.6%), prolonged PL lifetimes (1.78 ms), and enhanced thermal endurance (523 K) as a result of efficient Mn2+ doping (3.66%) induced by the addition of CuCl2. Furthermore, we applied pressure on Mn2+/Cu2+-codoped CsPbCl3 NCs to reveal that a red shift of photoluminescence followed by a blue shift was caused by band gap evolution and related to the structural phase transition from cubic to orthorhombic. Moreover, we also found that under the preheating condition of 523 K, such phase transition exhibited obvious morphological invariance, accompanied by significantly enhanced conductivity. The pressure applied to the products treated with high temperature enlarged the electrical difference and easily intensified the interface by closer packaging. Interestingly, defect-triggered mixed ionic and electronic conducting (MIEC) was observed in annealed NCs when the applied pressure was 2.9 GPa. The pressure-dependent ionic conduction was closely related to local nanocrystal amorphization and increased deviatoric stress, as clearly described by in situ impedance spectra. Finally, retrieved products exhibited better conductivity (improved by 5-6 times) and enhanced photoelectric response than those when pressure was not applied. Our findings not only reveal the pressure-tuned optical and electrical properties via structural progression but also open up the promising exploration of more amorphous all-inorganic CsPbX3-based photoelectric applications.

Mn2+/Yb3+ Codoped CsPbCl3 Perovskite Nanocrystals with Triple-Wavelength Emission for Luminescent Solar Concentrators.

Doping metal ions into lead halide perovskite nanocrystals (NCs) has attracted great attention over the past few years due to the emergence of novel properties relevant to optoelectronic applications. Here, the synthesis of Mn2+/Yb3+ codoped CsPbCl3 NCs through a hot‐injection technique is reported. The resulting NCs show a unique triple‐wavelength emission covering ultraviolet/blue, visible, and near‐infrared regions. By optimizing the dopant concentrations, the total photoluminescence quantum yield (PL QY) of the codoped NCs can reach ≈125.3% due to quantum cutting effects. Mechanism studies reveal the efficient energy transfer processes from host NCs to Mn2+ and Yb3+ dopant ions, as well as a possible inter‐dopant energy transfer from Mn2+ to Yb3+ ion centers. Owing to the high PL QYs and minimal reabsorption loss, the codoped perovskite NCs are demonstrated to be used as efficient emitters in luminescent solar concentrators, with greatly enhanced external optical efficiency compared to that of using solely Mn2+ doped CsPbCl3 NCs. This study presents a new model system for enriching doping chemistry studies and future applications of perovskite NCs.

Quantum yield enhancement of Mn-doped CsPbCl3 perovskite nanocrystals as luminescent down-shifting layer for CIGS solar cells

The emission and absorption properties of Mn doped CsPbCl3 NC make it ideal candidates as luminescent down shifting layer material for solar cells, However, effective Mn doping and further quantum yield improvement remains challenging. We present our modified hot injection route to obtain Mn doped CsPbCl3 nanocrystals with different morphologies and enhanced quantum yield. The samples presented were synthesized with precursor MnCl2 and PbCl2 with the ratio of 1:1, 1:2, 1:2.5 and 1:3. For samples with lower Mn doping level, the as prepared samples are uniform nanocubes with average size of 11 nm. When MnCl2 amount is increased beyond 2.5, large piece of nanosheets were found by TEM and AFM with ultrathin thickness and strong quantum confinement effect. CsPbCl3 nanocrystals with optimal Mn doping level show enhanced quantum yield of 69%. Luminescent down shifting layers prepared from Mn doped CsPbCl3 nanocrystals successfully increased short-circuit current (6.67%) and PCE (1.67%) of Cu(In,Ga)Se2 solar cell.

Triplet Energy Transfer from Perovskite Nanocrystals Mediated by Electron Transfer.

Triplet energy transfer from colloidal nanocrystals is a novel approach to sensitizing molecular triplets that are important for many applications. Recent studies suggest that this triplet transfer can be mediated by a hole transfer process when it is energetically allowed. In contrast, electron-transfer-mediated triplet transfer has not been observed yet, which is likely due to hole-trapping in typical II-VI group nanocrystals inhibiting the hole transfer step following initial electron transfer and hence disrupting a complete triplet exciton transfer. Here we report electron-transfer-mediated triplet energy transfer from CsPbCl3 and CsPbBr3 perovskite nanocrystals to surface-anchored rhodamine molecules. The mechanism was unambiguously established by ultrafast spectroscopy; control experiments using CdS nanocrystals also confirmed the role of hole-trapping in inhibiting this mechanism. The sensitized rhodamine triplets engaged in a variety of applications such as photon upconversion and singlet oxygen generation. Compared to conventional one-step triplet transfer, the electron-transfer-mediated mechanism is less demanding in terms of interfacial electronic coupling and hence is more generally implementable. Overall, this study not only establishes a complete framework of triplet energy transfer across nanocrystal/molecule interfaces but also greatly expands the scope of molecular triplet sensitization using nanocrystals.

Localized Surface Plasmon Resonance Enhanced Light Absorption in AuCu/CsPbCl3 Core/Shell Nanocrystals

Localized surface plasmon resonance (LSPR) is shown to be effective in trapping light for enhanced light absorption and hence performance in photonic and optoelectronic devices. Implementation of LSPR in all-inorganic perovskite nanocrystals (PNCs) is particularly important considering their unique advantages in optoelectronics. Motivated by this, the first success in colloidal synthesis of AuCu/CsPbCl3 core/shell PNCs and observation of enhanced light absorption by the perovskite CsPbCl3 shell of thickness in the range of 2-4 nm, enabled by the LSPR AuCu core of an average diameter of 7.1 nm, is reported. This enhanced light absorption leads to a remarkably enhanced photoresponse in PNCs/graphene nanohybrid photodetectors using the AuCu/CsPbCl3 core/shell PNCs, by more than 30 times as compared to the counterparts with CsPbCl3 PNCs only (8-12 nm in dimension). This result illustrates the feasibility in implementation of LSPR light trapping directly in core/shell PNCs for high-performance optoelectronics.

Increasing photoluminescence yield of CsPbCl3 nanocrystals by heterovalent doping with Pr3+

CsPbCl3 perovskite nanocrystals are doped with heterovalent Pr3+ using hot-injection method. These Pr3+-doped CsPbCl3 nanocrystals exhibit a dramatically improved absolute photoluminescence quantum yield (PLQY) compared to the undoped CsPbCl3, reaching 78.9 % PLQY at 9 % Pr-substitution. The crystal structure modification upon Pr3+ doping and luminescence mechanism are investigated using conventional optical spectroscopy and synchrotron X-ray spectroscopy (i.e., X-ray absorption fine structure and X-ray excited optical luminescence). Both the Pr3+ and Cl− are found contributing to the luminescence enhancement, and their individual roles in luminescence enhancement are analyzed.

Ligand Engineering for Mn2+ Doping Control in CsPbCl3 Perovskite Nanocrystals via a Quasi-Solid–Solid Cation Exchange Reaction

Manganese-doped cesium lead chloride (CsPbCl3) perovskite nanocrystals (NCs) have recently garnered attention because of their unique magneto-optical properties, giving them potential in a variety ...