Tunable Color Temperatures and Emission Enhancement in 1D Halide Perovskites under High Pressure

Abstract

Designing low‐dimensional halide perovskites (LDHPs) for broadband emissions with enhanced emission and preferred chromaticity coordinator or color temperature remains a pressing challenge. Herein, a comprehensive study is conducted about the relationship between the crystal structure and broadband emission properties of 1D halide perovskite C4N2H14PbBr4, one of promising white‐emission LDHPs. It is found that the zigzag distortion degree tuned by pressure not only suppresses the general photoluminescence quenching, but also effectively adjusts the chromaticity coordinator and color temperature of C4N2H14PbBr4 nanocrystals (NCs). The initially broad white emissive C4N2H14PbBr4 NCs can be continuously modulated to a very bright bluish‐white emission with high color‐rendering index of 86, accompanied by a significant emission enhancement. The underlying mechanism of thus pressure‐induced emission enhancement (PIEE) can be attributed to the strengthening of electron–phonon interactions of compressed C4N2H14PbBr4 NCs. Furthermore, the zigzag distortion of [PbBr42−]∞ octahedral chains is able to rearrange the depths of multiple self‐trapped states, which is also corroborated by the wavelength‐dependent decay times under pressure, ultimately giving rise to adjustable emission chromaticity. This study offers a deep insight into the relationship between PIEE and distortion degree of LDHPs at extremes and facilitates the design of new materials with the desired emission properties.

Highly Luminescent Metal‐Free Perovskite Single Crystal for Biocompatible X‐Ray Detector to Attain Highest Sensitivity

“…[ 26,27 ] The corresponding Commission Internationale de l'Éclairage (CIE) coordinates of the emission are (0.04454, 0.3772) at room temperature (Figure 3B), which corresponds to a relative correlated color temperature of 2500 K and warm orange light. [ 15 ]…”

“…[ 10 ] Despite the initial discovery, and a similar paper on perchlorate perovskites in 2011, [ 11 ] advancements have been reported only during the past two years, including an understanding of their optically active non‐centrosymmetric, ferroelectric and mechanical properties [ 12,13 ] and, most recently, their intrinsic charge transport properties. [ 14 ] The rich investigations of metal‐based perovskites have enabled discoveries of how charges recombine for light emission, color tuning, bandgap tuning by manipulating the structure, and charge extraction control for better photoresponse, [ 15–17 ] which place metal‐based halide perovskites in a dominant position for perovskite optoelectronics. However, in contrast to their metal‐based analogs, for metal‐free perovskites, these fundamental properties still remain largely unexplored.…”

Harvesting Cool Daylight in Hybrid Organic–Inorganic Halides Microtubules through the Reservation of Pressure‐Induced Emission

“…demonstrated that an optimal distortion in metal halide perovskites is preferred to determine the PIE. [ 26,28–30 ] In addition, Li et al. reported an irreversible phase transition of acetamidinium nitrate by introducing CH 3 to impart steric hindrance, thus increasing the potential barrier of phase transition to stabilize the high‐pressure phase.…”

Self-trapped exciton emission and piezochromism in conventional 3D lead bromide perovskite nanocrystals under high pressure

“…22 Thus, PIE provides distinct advantages for light-emitting applications achievable by the design of structural distortion. [23][24][25][26] Localization of carriers resulting from a low electronic dimension and seriously distorted metal halide octahedra enhance the optical activity and binding energy of STEs. Therefore, the radiative recombination of STEs may also be activated in doped 3D perovskite materials with local carriers by continuously tuning the structural distortion with the assistance of a high-pressure method.…”