Kong Lingping, Liu Gang, Gong Jue, Mao Lingling, Chen Mengting, Hu Qingyang, Lü Xujie, Yang Wenge, Kanatzidis Mercouri G, Mao Ho-Kwang
Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China.
Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China;
Proc Natl Acad Sci U S A. 2020 Jul 14;117(28):16121-16126. doi: 10.1073/pnas.2003561117. Epub 2020 Jun 29.
The application of pressure can achieve novel structures and exotic phenomena in condensed matters. However, such pressure-induced transformations are generally reversible and useless for engineering materials for ambient-environment applications. Here, we report comprehensive high-pressure investigations on a series of Dion-Jacobson (D-J) perovskites A'A Pb I [A' = 3-(aminomethyl) piperidinium (3AMP), A = methylammonium (MA), = 1, 2, 4]. Our study demonstrates their irreversible behavior, which suggests pressure/strain engineering could viably improve light-absorber material not only in situ but also ex situ, thus potentially fostering the development of optoelectronic and electroluminescent materials. We discovered that the photoluminescence (PL) intensities are remarkably enhanced by one order of magnitude at mild pressures. Also, higher pressure significantly changes the lattices, boundary conditions of electronic wave functions, and possibly leads to semiconductor-metal transitions. For (3AMP)(MA)PbI, permanent recrystallization from 2D to three-dimensional (3D) structure occurs upon decompression, with dramatic changes in optical properties.
施加压力可以在凝聚态物质中实现新颖的结构和奇异的现象。然而，这种压力诱导的转变通常是可逆的，对于环境应用的工程材料来说并无用处。在此，我们报告了对一系列狄昂 - 雅各布森（D-J）钙钛矿A'A Pb I [A' = 3-(氨甲基)哌啶鎓（3AMP），A = 甲胺鎓（MA）， = 1, 2, 4]进行的全面高压研究。我们的研究证明了它们的不可逆行为，这表明压力/应变工程不仅可以原位而且可以异位切实地改善光吸收材料，从而有可能促进光电子和电致发光材料的发展。我们发现，在温和压力下光致发光（PL）强度显著增强了一个数量级。此外，更高的压力会显著改变晶格、电子波函数的边界条件，并可能导致半导体 - 金属转变。对于(3AMP)(MA)PbI，减压时会发生从二维到三维（3D）结构的永久重结晶，光学性质会发生显著变化。
