Steric hindrance effects on the retention of pressure-induced emission toward scintillators

The success in pressure-induced emission (PIE) from hybrid perovskites greatly facilitates the potential development of high-efficiency white-light-emitting diodes and scintillators. However, its reversibility essentially inhibits practical applications. Furthermore, the urgent demand for scintillators requests fast decay response time and a large Stokes shift that suppresses self-adsorption. Here, we report the quantitative steric hindrance effect of different organic components in hybrid perovskites. Moreover, 1-(2-naphthyl)methanamine (NAPH)+ with a complex configuration is further introduced to experimentally prepare the 2D hybrid perovskite (NAPH)2PbCl4 nanoplates. Notably, benefiting from the increased barrier of phase transition associated with a high steric effect index (SEI) of 5.98, the harvested amorphous phase exhibits twice more intensity than the initial emission, a shortened decay time of 1.73 ns, and an enlarged Stokes shift of 260.7 nm. This study establishes the correlation between PIE retention and steric hindrance, improving the material design and synthesis for applications in white-light-emitting diodes and scintillators.