Cao XiuHong, Chang ZhenYun, Chang Jing
Opt Lett. 2024 Feb 1;49(3):534-537. doi: 10.1364/OL.509751.
Tuning the structure-property relations of perovskites by pressure engineering holds great promise for discovering materials with favorable properties. The newly synthesized CsPtBr double perovskite exhibits excellent water resistance and chemical stability. Yet its photoelectric conversion efficiency is limited by its intrinsic wide-bandgap nature. In this work, based on density functional theory calculations, we demonstrate the bandgap narrowing of CsPtBr via pressure engineering and maintain its structural stability. Strikingly, upon applying pressure up to 12 GPa, the bandgap value decreases to 1.34 eV, which exactly reaches the optimal bandgap required by the Shockley-Queisser efficiency limit. Moreover, optical calculation analysis shows that the optical absorption of CsPtBr exhibits a significant improvement within the visible range. Therefore, the potential of CsPtBr as a photovoltaic material by pressure engineering is improved. This work is useful for designing and synthesizing new perovskite materials with enhanced performance.
通过压力工程调节钙钛矿的结构-性能关系对于发现具有良好性能的材料具有巨大潜力。新合成的CsPtBr双钙钛矿表现出优异的耐水性和化学稳定性。然而，其光电转换效率受到其固有的宽带隙性质的限制。在这项工作中，基于密度泛函理论计算，我们证明了通过压力工程可以使CsPtBr的带隙变窄并保持其结构稳定性。令人惊讶的是，在施加高达12 GPa的压力时，带隙值降至1.34 eV，恰好达到肖克利-奎塞尔效率极限所需的最佳带隙。此外，光学计算分析表明，CsPtBr的光吸收在可见光范围内有显著改善。因此，通过压力工程提高了CsPtBr作为光伏材料的潜力。这项工作对于设计和合成具有增强性能的新型钙钛矿材料很有用。
