在IrO2上的吸附位点的表征,通过编程O2的温度,进行脱吸模拟
Vivianne K Ocampo-Restrepo1, Sudarshan Vijay1, G T Kasun Kalhara Gunasooriya2
1Department of Physics, Technical University of Denmark (DTU), Lyngby, Denmark. jkno@dtu.dk.
Physical chemistry chemical physics : PCCP
|June 11, 2024
概括
从氧化 (IrO2) 中氧气脱吸的模拟显示,多个吸附点,包括与阶段相关的吸附点,对于准确建模温度编程脱吸 (TPD) 配置文件和理解表面反应至关重要.
科学领域:
- 表面科学是一门学科.
- 计算化学计算化学
- 催化剂是一种催化剂.
背景情况:
- 在氧氧氧化物 (IrO2) 上的氧气吸附和溶解对氧气演化反应 (OER) 至关重要.
- 了解这些基本步骤的动力学需要精确地建模表面过程.
- 密度函数理论 (DFT) 为表面能量计算提供了有价值的数据.
研究的目的:
- 为了模拟氧 (O2) 从IrO2的温度编程脱吸 (TPD) 配置文件 (O2),使用DFT衍生的脱吸能量.
- 研究不同吸附点和表面覆盖在O2脱吸动力学上的作用.
- 为OER等催化应用提供有关IrO2表面活性的见解.
主要方法:
- 使用密度函数理论 (DFT) 来计算氧气吸附和脱附能量在IrO2上.
- 开发和应用计算模型来模拟温度编程脱吸 (TPD) 配置文件.
- 将模拟的TPD数据与各种氧气覆盖范围的实验结果进行比较.
主要成果:
- 在原始的IrO2 ((110) 上,即使在高覆盖率下,最稳定的氧气吸附点也被确定为IrCUS.
- 在结合多个吸附点时,模拟准确地重现了实验TPD数据.
- 确定了一种新的与阶段相关的吸附部位 (IrCUS-step-0.5) 对于匹配实验TPD配置文件至关重要.
- 观察到的TPD峰值归因于不同的吸附点,而不仅仅是侧面相互作用.
结论:
- 多个吸附点,包括在表面步骤上的吸附点,显著影响IrO2的氧气脱吸行为.
- 集成DFT数据和多个吸附点的计算模拟对于预测实验TPD结果是有效的.
- 这项研究增强了对IrO2氧表面化学的理解,影响了催化研究,特别是对OER.
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