Affiliation:
1. College of Chemistry and Chemical Engineering Qingdao University Qingdao 266071 China
2. School of Materials Science and Engineering Smart Sensing Interdisciplinary Science Center Nankai University & TKL of Metal and Molecule Based Material Chemistry Tianjin 300350 China
3. School of Physics Huazhong University of Science and Technology Wuhan 430074 China
4. Key Laboratory of Functional Inorganic Materials Chemistry (Ministry of Education) & School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China
Abstract
AbstractThe engineering of tunable photoluminescence (PL) in single materials with a full‐spectrum emission represents a highly coveted objective but poses a formidable challenge. In this context, the realization of near‐full‐spectrum PL emission, spanning the visible light range from 424 to 620 nm, in a single‐component two‐dimensional (2D) hybrid lead halide perovskite, (ETA)2PbBr4 (ETA+=(HO)(CH2)2NH3+), is reported, achieved through high‐pressure treatment. A pressure‐induced phase transition occurs upon compression, transforming the crystal structure from an orthorhombic phase under ambient conditions to a monoclinic structure at high pressure. This phase transition driven by the adaptive and dynamic configuration changes of organic amine cations enables an effective and continuous narrowing of the band gap in this halide crystal. The hydrogen bonding interactions between inorganic layers and organic amine cations (N−H⋅⋅⋅Br and O−H⋅⋅⋅Br hydrogen bonds) efficiently modulate the organic amine cations penetration and the octahedral distortion. Consequently, this phenomenon induces a phase transition and results in red‐shifted PL emissions, leading to the near‐full‐spectrum emission. This work opens a possibility for achieving wide PL emissions with coverage across the visible light spectrum by employing high pressure in single halide perovskites.