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 C 4 N 2 H 14 PbBr 4 , 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 C 4 N 2 H 14 PbBr 4 nanocrystals (NCs). The initially broad white emissive C 4 N 2 H 14 PbBr 4 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 C 4 N 2 H 14 PbBr 4 NCs. Furthermore, the zigzag distortion of [PbBr 4 2− ] ∞ 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.