有機-無機雜化鹵化物鈣钛礦材料具有卓越的光電性能，并在太陽能電池，光電探測器，發光二極管、閃爍體和光電池中得到了一定的應用。然而，與矽或石墨烯不同，鹵化物鈣钛礦在日常環境條件下非常不穩定。例如，鹵化物鈣钛礦材料在氧氣和水蒸氣等大氣分子的存在下會迅速降解，進而削弱器件和裝置性能。了解和優化其水環境中光電化學性質對于開發高效和可持續的能量轉換和存儲技術(包括太陽能電池、水分解系統、光催化劑和環境傳感器)至關重要。考慮到分子和表面工程鹵化物鈣钛礦的高度複雜和多元虛拟設計空間，需要進行更全面和系統的研究，以獲得最佳的分子/鈣钛礦複合體系，該體系在水溶液等惡劣條件下具有良好的光電性能和水穩定性。
來自中國南京資訊工程大學的張磊教授及其團隊成員，基于機器學習和材料計算，科學地評估了鹵化物鈣钛礦的穩定性。在這項研究中，他們系統地研究了在不同表面上功能的多分子修飾的CH3NH3PbI3膜的水性光電化學穩定性，發現了一種有效的多分子鈣钛礦材料體系“calcein + PbBr2 + DMSO +CH3NH3PbI3”，具有出色的液态水環境光電穩定性（相同水環境下光生電流是CH3NH3PbI3薄膜輸出的103倍)和92.5%的水穩定性。随後，通過遺傳算法和極端随機樹的Shapley分析來檢測分子修飾鈣钛礦材料的實驗水性光電化學性質，以提供機器解釋和解耦分子貢獻，強調這些相容分子的協同效應及其親水/親脂性對目标輸出的重要性。DFT計算表明，該多分子全局優化體系存在大量氫鍵和陰離子··π表面互相作用以穩定其界面結構。除了預測高水穩定性的鈣钛礦體系外，該研究團隊還優化了光電化學、機器學習和DFT模型總體資料驅動工作流程用于評估鹵化物鈣钛礦穩定性。
該文近期發表于npj Computational Materials | (2024) 10:114，英文标題與摘要如下，點選https://www.nature.com/articles/s41524-024-01297-4可以自由擷取論文PDF。
Figure 1 Post-hoc DFT calculation (atomic and electronic structures)
Figure 2 Fabrication details, classification method and molecular variables.
Figure 3 Feature analysis via SHAP.
Figure 4 Overall workflow of this study.
Data-driven optimization and machine learning analysis of compatible molecules for halide perovskite material
Shaojun Wang, Yiru Huang, Wenguang Hu & Lei Zhang
Optoelectronic stability of halide perovskite material in hostile conditions such as water is rather limited, preventing them from further industrial deployment. Here, we optimize and perform machine learning analysis on CH3NH3PbI3materials with additives, solvents and post-treatment molecules using combined experimental and data-driven methods. A champion system consisting of a compatible tertiary molecular combination ‘calcein+PbBr2 + DMSO’ active at diverse surfaces is identified, delivering a large aqueous photoelectrochemical (PEC) photocurrent of 10-5 A/cm2 and an improved aqueous stability of 92.5%. Subsequently, machine interpretation is provided to decouple the multi-molecule contributions with the assistance of genetic programming (GP) and extra-trees (ET) machine learning models, highlighting the intricate molecular features for the target outputs. The posthoc density functional theory (DFT) calculation suggests the presence of multiple hydrogen bond and anion··π surface interactions to stabilize the interfacial structures. The present ‘PEC + GP + ET + DFT’ approach is suggested to be an effective approach to design and comprehensively evaluate moleculemodified materials.