Soochow Institute for Energy and Materials Innovations (SIEMIS), College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, and ‡Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University , Suzhou 215006, China.
J Am Chem Soc. 2017 Oct 25;139(42):14905-14908. doi: 10.1021/jacs.7b09379. Epub 2017 Oct 11.
Stability is of central importance in current perovskite solar cell research and applications. Goldschmidt tolerance factor (t) recently provided qualitative guidance for experimentalists to engineer stable ABX perovskite by tuning effective ionic size with mixing cations or anions and for theorists to search emerging perovskites. Through first-principles calculations, we have calculated decomposition energies of 138 perovskite compounds of potential solar cell applications. Instead of t, we have found that (μ + t), where μ and η are the octahedral factor and the atomic packing fraction, respectively, demonstrates a remarkably linear correlation with thermodynamic stability. As a stability descriptor, (μ + t) is able to predict the relative stability among any two perovskites with an accuracy of ∼90%. This trend is then used to predict decomposition energies of another 69 perovskites, and the results are in excellent agreement with first-principles calculations, indicating the generalization of the trend. This thermodynamic stability trend may help the efficient high-throughput search for emerging stable perovskites and precise control of chemical compositions for stabilizing current perovskites.
稳定性是当前钙钛矿太阳能电池研究和应用的核心问题。戈尔德施密特容忍因子（t）最近为实验人员提供了定性指导，通过混合阳离子或阴离子来调整有效离子尺寸，从而设计出稳定的 ABX 钙钛矿；也为理论研究人员寻找新兴的钙钛矿提供了方向。通过第一性原理计算，我们计算了 138 种潜在太阳能电池应用的钙钛矿化合物的分解能。我们发现，（μ + t）与热力学稳定性具有显著的线性相关性，而不是 t，其中 μ 和 η 分别是八面体因子和原子堆积分数。作为稳定性描述符，（μ + t）能够以约 90%的准确度预测任意两种钙钛矿之间的相对稳定性。然后，我们使用该趋势来预测另外 69 种钙钛矿的分解能，结果与第一性原理计算非常吻合，表明了该趋势具有普遍性。这种热力学稳定性趋势可能有助于高效高通量地寻找新兴的稳定钙钛矿，并精确控制当前钙钛矿的化学成分以实现稳定。
