论文标题
卤化物钙钛矿中的缺陷：它有助于从3D切换到2D吗？
Defects in Halide Perovskites: Does It Help to Switch from 3D to 2D?
论文作者
论文摘要
Ruddlesden-Popper混合碘化物2D Perovskites是其3D对应物的稳定替代品。 Using first-principles calculations, we demonstrate that equilibrium concentrations of point defects in the 2D perovskites PEA$_2$PbI$_4$, BA$_2$PbI$_4$, and PEA$_2$SnI$_4$ (PEA: phenethyl ammonium, BA: butylammonium), are much lower than in comparable 3D perovskites.与3D网络相比，在2D中，缺陷的粘结破坏更有害，从而使缺陷形成在能量上更加昂贵。通过与Pb合金合金可以进一步增强2D SN碘化钙钛矿的稳定性。但是，应由于非平衡生长条件而导致的浓度相当大的浓度，例如，这些缺陷会在引入深层陷阱时妨碍2D Perovskites的光电性能。我们建议，陷阱水平是导致在实验中观察到的2D钙化物中广泛的子带gap发射的原因。
Ruddlesden-Popper hybrid iodide 2D perovskites are put forward as stable alternatives to their 3D counterparts. Using first-principles calculations, we demonstrate that equilibrium concentrations of point defects in the 2D perovskites PEA$_2$PbI$_4$, BA$_2$PbI$_4$, and PEA$_2$SnI$_4$ (PEA: phenethyl ammonium, BA: butylammonium), are much lower than in comparable 3D perovskites. Bonding disruptions by defects are more detrimental in 2D than in 3D networks, making defect formation energetically more costly. The stability of 2D Sn iodide perovskites can be further enhanced by alloying with Pb. Should, however, point defects emerge in sizable concentrations as a result of nonequilibrium growth conditions, for instance, then those defects hamper the optoelectronic performance of the 2D perovskites, as they introduce deep traps. We suggest that trap levels are responsible for the broad sub-bandgap emission in 2D perovskites observed in experiments.
