Perovskite Nanocrystal Heterostructures: Synthesis, Optical Properties, and Applications

Abstract

Bringing together two nanostructures of different materials in a single building block can create a new platform where both can share their electronic and optical characteristics. While these have been extensively studied for metal nanoparticles and chalcogenide semiconductor nanocrystals, the literature is limited for perovskite nanocrystals. Because perovskite nanocrystals typically follow a fast formation process and also require a specific environment, their growth on other materials or vice versa indeed remains difficult. However, some success has been achieved in lead halide perovskites with several metal halides, oxides, and chalcogenides and also with noble metals. These findings indeed opened up new directions for designing perovskite nanocrystal heterostructures, investigating their heterojunctions, analyzing new properties, and exploring their possible utilizations. Summarizing all these developments, this Focus Review demonstrates challenges associated with their formation, changes in their optical properties, stability, and several applications. In addition, this work addresses a few possible future research directions regarding these perovskite heterostructures.

CsPbBr3–CdS heterostructure: stabilizing perovskite nanocrystals for photocatalysis

“…The bleach recovery was analyzed using a biexponential kinetic fit 35 and the fitting parameters ( a 1 , τ 1 ) and ( a 2 , τ 2 ) corresponding to fast and slow components are presented in Table S3. † While the fast component varied in the range 18.6–6.6 ps the long component varied in the range of 129.6–71.7 ps.…”

“…[30][31][32][33] Designing perovskite heterostructures with metal chalcogenide shells can have several distinct advantages: (i) providing stability towards increased polarity of the solvent, (ii) remediating surface defects by directly interacting with the vacancies, and (iii) allowing for type I or quasi-type II band alignment to promote increased charge recombination in the core (increased emission yield) or improved charge separation. [34][35][36] In this context, a CsPbBr 3 -CdS heterostructure offers an attractive means to tune the band energies, as their conduction bands are nearly isoenergetic (E CB of CsPbBr 3 and quantized CdS z À0.8 V versus NHE) [37][38][39] and facilitate charge separation. In addition, cubic CsPbBr 3 nanocrystals have a lattice constant (a) of 5.85 Å (ref.…”

Halide Perovskite Nanocrystal Emitters

“…Engineering of nanocrystal heterostructures based on perovskite platform is a novel concept to achieve optoelectronic materials with synergetically improved characteristics. [ 139 ] Heterostructures made of all‐inorganic PNCs and lead sulfide (PbS) QDs provide a unique opportunity to utilize the strong PL in the NIR from QDs far inside the matrix of the nanosized perovskite material. Zhang et al have recently reported the RT synthesis of heterostructured CsPbX 3 –PbS PNCs with a dual emission.…”

Recent Progress in Designing Halide-Perovskite-Based System for the Photocatalytic Applications

“…From the photocatalytic or photoelectrocatalytic point of view, it is noteworthy that the halide perovskite possesses a suitable band structure for the CO 2 reduction. In recent years, some studies on the CO 2 reduction with halide perovskite driven by visible light have been reported (Bera and Pradhan, 2020 ; Shyamal and Pradhan, 2020 ; Wang H. et al, 2020 ). For the reported work involving the CO 2 reduction using perovskite-based photocatalysts, the detailed reaction conditions have been summarized and listed in Table 4 .…”