All‐Inorganic Lead‐Free Perovskite(‐Like) Single Crystals: Synthesis, Properties, and Applications

Abstract

Due to their nontoxicity, stability, and unique optoelectronic properties, all‐inorganic lead‐free halide semiconductors with perovskite and perovskite‐like structures have successfully emerged as promising optoelectronic materials for various applications, such as solar cells, light‐emitting diodes (LEDs), photodetectors, and X‐ray detectors. To further explore their practical potentials, researchers have paid more attention in all‐inorganic lead‐free perovskite (‐like) (ILFP) single crystals. For these single crystals, the advantages of large sizes, uniform surface morphology, and few defects can facilitate their excellent performances and practical applications. Besides, compared with the low dimensional and polycrystalline ILFP materials, the ILFP single crystals feature enhanced performances, including a longer carrier diffusion length and a larger light absorption coefficient, which attract a great deal of attention. Therefore, focus is on the researching progress of ILFP single crystals and the development of their preparation methods, as well as the novel properties of ILFP single crystals. In addition, the reported applications of ILFP single crystals are proposed to highlight their practical importance. With the perspective of the evolution and challenges, the current limitations of the materials and devices are discussed, followed by an inspirational outlook on their future development directions.

Symmetry breaking of A3M2X9-type perovskite derivatives induced by polar quaternary ammonium cations: achieving efficient nonlinear optical properties

“…In recent years, organic-inorganic hybrid perovskites, as a new multifunctional material with diverse structures and lowcost solution processability, have attracted particular attention for their dramatic advances in photovoltaic devices, solid-state lighting and displays. [17][18][19][20] The general chemical formula of a classic lead halide perovskite is APbX 3 , where A is a monovalent cation such as Cs + , methylammonium (CH 3 NH 3 + ), formamidinium (HC(NH 2 ) 2 + ) or methylhydrazinium (CH 3 NH 2 NH 2 + ) and X is a halide ion. [21][22][23] Lead is known to be toxic and degrades slowly, which would hinder its commercial applications.…”

Recent Advances in All‐Inorganic Zero‐Dimensional Metal Halides

“…reported that 0D Cs 4 EuX 6 showed excellent scintillation properties under the excitation of gamma‐ray. The high scintillation yield for Cs 4 EuBr 6 was reported as 78000±4000 photons/MeV under 137 Cs gamma‐ray irradiation, which is better than that of the commercial scintillator NaI:TI and among the highest self‐activated scintillators so far [21] …”

“…In recent years, the synthesis is mainly directed to wet‐chemistry techniques due to lower cost and better accessibility. By proper selection of solvents and precursor chemicals, wet‐chemistry methods can be readily adapted to synthesize various 0D metal halides with controllable sizes down to several nanometers [21] . The wet‐chemistry synthesis of current interest mainly includes antisolvent method, coprecipitation method, hot injection method.…”

Lead-Free Perovskite Single Crystals: A Brief Review

“…In terms of structure, Pb 2+ cations are separated by six neighbor X-site anions to bulid Pb-X octahedrons, which corner-share with each other to constitute the main frame and A + intercalates the voids [24]. The replacement of Pb 2+ with lead-free ions results in both the deformation in nanoscale structure and the conversion of properties because of the differences in chemical valence and ion size [23]. Therefore, LFPSCs exhibit plenty of novelty and diversity, we discussed several typical LFPSCs in this section and summarized in Table 1, along with the schematic diagrams of synthesis methods as shown in Figure 1.…”

“…Though a number of efforts have been devoted to develop various LFPCs, a lack of comprehensive understanding towards the synthesis methods, properties, and the device performance still restrict their practical application. To promote the development of LFPSCs, we mainly focus on summarizing the up-to-date advancement of several representative PSCs and their applications in photodetectors, photovoltaics solar cells, X-ray detectors, light-emitting diodes (LEDs), and other devices [23]. To be specific, various systems including replacement of Pb-based perovskites, perovskite-like derivate and double perovskites are presented.…”