RUI: Understanding how dopant affects preferred proton conduction pathways in perovskite oxides

芒特霍利奥克学院的玛丽亚·戈麦斯获得了鲁伊奖的支持，该奖项旨在了解掺杂剂的大小和电子特性如何影响首选的质子传导路径。我们将对掺杂钙钛矿氧化物进行系统的研究。特别是，最小能量结合位、过渡态活化能和过渡态前因数将作为掺杂剂的函数进行计算。利用邻接矩阵和动力学蒙特卡罗方法，在相对位置能和前置因子的条件下，可以找到能量和运动学上较好的路径。从分子动力学计算开始，在首选传导路径内的不同结合位置，振动光谱将被计算出来。与实验的比较将有助于将光谱特征与OH振动和不同的结合位置关联起来。最后，在掺杂的钙钛矿中添加质子如何改变结合能、过渡态和最低能量路径的研究将开始。钙钛矿氧化物中的质子传导在燃料电池技术、湿度传感器和电池中具有潜在的应用。从这项研究中获得的知识有望有助于设计高效的质子传导钙钛矿。该项目对未来科学家的培养产生了更广泛的影响，完全由曼荷莲学院的本科生研究人员参与，该学院是美国历史最悠久的女性文科进修本科学院。学生参与者将在国家或地区会议以及合著者出版物上展示他们的本科生研究成果。

Maria Gomez of Mount Holyoke College is supported by a RUI award for research that aims to understand how dopant size and electronic character affect preferred proton conduction pathways. A systematic study of doped perovskite oxides will be carried out. In particular, minimum energy binding sites, transition state activation energies, and transition state pre-factors will be calculated as a function of dopant. With relative site energies and pre-factors, the energetically and kinetically preferred pathways will be found using adjacency matrices and Kinetic Monte Carlo. From molecular dynamics calculations starting at different binding sites within the preferred conduction pathways, vibrational spectra will be calculated. Comparisons with experiment will help correlate spectral features with OH vibrations and different binding sites. Finally, investigations into how the addition of protons into doped perovskites changes binding energies, transition states, and lowest energy pathways will begin.Proton conduction in perovskite oxides has potential applications in fuel cell technologies, humidity sensors, and batteries. The knowledge gained from this research is expected to aid in designing efficient proton conducting perovskites. This project has a broader impact in the training of future scientists, and is being carried out entirely with undergraduate student researchers at Mount Holyoke College, the oldest continuing undergraduate liberal arts college for women in the United States. The student participants will present their undergraduate research at national or regional meetings, and co-author publications.