有机无机杂化钙钛矿体系中有机组分对材料性质影响机制的理论研究
批准号:
22103012
项目类别:
青年科学基金项目(C类)
资助金额:
30.0 万元
负责人:
吴天敏
依托单位:
学科分类:
化学模拟与应用
结题年份:
2024
批准年份:
2021
项目状态:
已结题
项目参与者:
吴天敏
中文摘要
快速开展高性能功能材料搜索和设计,有赖于对材料构效关系的深刻理解。本项目拟结合密度泛函理论和机器学习方法,以有机无机杂化钙钛矿体系为研究对象,发展一套能够有效剖析复杂材料体系构效关系且具有泛化能力的理论方案。虽然有机无机杂化钙钛矿材料在光伏洁净能源领域应用潜力巨大,但自身毒性和不稳定性却严重制约其广泛应用,且有机组分对材料性质及稳定性作用机制仍不明晰。针对原子信息描述符无法准确描述具有复杂结构的有机组分这一现实,本项目拟从有机组分角度出发,深入剖析有机组分内禀属性与材料性质及结构稳定性之间的深层次关联,进而构建准确表征材料性质的描述符和探寻有效界定材料稳定性的全新判据,以期加速材料搜索和设计。此外,本项目拟透过同分异构体系横向比较揭示有机组分对材料性质作用机理,以突破有机阳离子彼此巨大差异化所限制纵向比较分析的藩篱,并有助提升数据集质量和多样性,助力机器学习模型构建及深层次关联剖析。
英文摘要
Rapidly discovering and designing high-performance functional materials seriously relies on a deep understanding of structure-property relationships. In this project, combining density functional theory calculations with machine learning techniques, a strategy with high generalization ability intends to be proposed to effectively establish structure-property relationships of hybrid organic-inorganic perovskites. Hybrid organic-inorganic perovskites, as one of the most promising materials for photovoltaics, possess a broad application prospect in the field of clear energy, however two key challenges of intrinsic instability and toxicity issues restrain its large-scale commercial applications and the underlying physics of organic components on the material properties are still unclear. Moreover, due to its complex structure, it hard to rely on atomic descriptors to accurately define organic cations. From the perspective of organic components in hybrid perovskites, the proposed theoretical method here is introduced to reveal the correlations between the intrinsic properties of organic components and the electronic properties and structural stability, thus construct a set of valid descriptors for accurately characterizing electronic structural properties and look for effective and innovative criterions to evaluate the structure stability, in order to accelerate the discovery and design of promising hybrid perovskites for photovoltaics. In addition, the microscopic mechanism of organic cations on electronic structural properties and stabilities here intend to be investigated via introducing comparisons between isomeric perovskites, which is expected to overcome the traditional analysis difficulties induced by giant difference between organic cations. Moreover, the improvements of quality and diversity of dataset here also benefit to promote machine learning model construction and intrinsic correlation analysis.
通过提取钙钛矿材料结构信息构造高维杂化钙钛矿数据库,运用多机器学习模型建立可靠构-效关系进而构建能够有效描述体系光电性质的晶体结构特征符,首次揭示八面体结构参数与光电性质之间的紧密关联,并通过加压诱导畸变模拟成功验证模型预测,印证所开发机器学习算法的强鲁棒性。针对无铅双钙钛矿和低维杂化钙钛矿光电材料设计及性质展开系统理论研究工作,通过机器学习所构筑光电材料组分-电子结构映射关系因忽略宇称禁戒跃迁而无法关联光学性质,首次明确要审慎依赖电子结构开展光电材料设计,并且表明长时间分子动力学模拟手段开展工况条件下构象分析才是评判所筛选体系热稳定性的强有力依据。此外,通过理论结合实验发现Na+/Bi3+掺杂Cs2AgInCl6具有~100%量子产率并通过多光子吸收产生高效稳定的上转换自陷激子态发射。通过引入稀土Nd3+掺杂,利用Na+/Bi3+共合金化诱导局域宇称禁戒跃迁破坏和电-声耦合降低,首次实现自陷激子发射和Nd3+近红外发射协同增强,并实现Td3+掺杂Cs2AgInCl6中诱导局域畸变降低局域对称性,实现自陷激子发射而产生纯白电致发光。透过纵声学支模型,我们发现Ni掺杂CsPbBr3有效强化体系电声耦合诱导声子软化,为打破热声子瓶颈构建有效Klemens输运通道以加速非辐射载流子复合,而通过卤素替代则会导致体系八面体畸变,削弱电子屏蔽和电声耦合,抑制俄歇复合而延长热载流子寿命。进而为理解和调控光电材料自陷激子发光机理和光生载流子弛豫机制提供了新颖视角。通过理论计算模拟引导实验在BaTiO3引入缺陷和掺杂,削弱极化各向异性并结合晶格局域畸变促进电子-空穴分离,从而大幅提升压电性能和声动力活性,后续包覆聚多巴胺(提供热载流子输运通道)表面吸附Cu2+构筑压电催化器件,通过诱导Cu氧化还原促进自由基产生,实现优异抗菌效果。
物理与数据双驱动的I-III-VI2族量子点结构和光谱性质预测
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批准号:22573014
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项目类别:面上项目
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资助金额:50.00万元
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批准年份:2025
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负责人:吴天敏
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依托单位:
国内基金
海外基金