可逆电极 (RHE) 尺度依赖的表面在不同pH值下的Pourbaix图
Heng Liu1, Di Zhang1, Yuan Wang1
1Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai 980-8577, Japan.
Langmuir : the ACS journal of surfaces and colloids
|March 29, 2024
概括
这项研究引入了依赖pH值的表面Pourbaix图用于电催化,改善了表面覆盖率的预测. 新方法将理论模型与实验观测结合在一起,这对于催化剂设计至关重要.
科学领域:
- 电触媒溶解是一种电触媒.
- 表面科学是一门学科.
- 计算化学计算化学
背景情况:
- 表面覆盖面对于电催化机制和催化剂设计至关重要.
- 表面Pourbaix图预测了从水激活中吸附剂的覆盖范围,但可能与可逆电极 (RHE) 规模的实验数据不一致,特别是在性条件下.
- 现有的模型没有完全考虑RHE尺度上的pH依赖的表面能量.
研究的目的:
- 开发一个pH取决于表面的普尔贝克斯图,适用于RHE尺度.
- 为了提高电催化剂表面覆盖面的理论预测的准确性.
- 为在电催化中分析表面覆盖面提供精细的方法.
主要方法:
- 密度函数理论 (DFT) 计算与贝叶斯误差估计函数与范德瓦尔斯校正 (BEEF-vdW) 用于计算能量.
- 纳入电场效应,吸附诱导的二极极矩,极化性和零电荷的潜力.
- 在RHE尺度上推导一个pH取决于表面的Pourbaix图,使用Pt(111) 进行验证.
主要成果:
- 拟议的RHE依赖表面普尔贝克斯图显著减少了理论预测和实验表面覆盖之间的差异.
- 改进后的模型在中性和中等电位条件下表现出特别高的准确性.
- 该方法为电催化剂评估提供了更精确的表面覆盖面分析.
结论:
- 开发的pH依赖表面普尔贝克斯图为理解电催化提供了更准确的理论框架.
- 这项工作为精确的表面覆盖率分析制定了指导方针,增强了电催化剂设计和活动评估.
- 这些发现对于推动电催化领域的发展至关重要,特别是对于中性到性环境中的应用.
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