在不同的电解质度下,光电极上的单个泡的生长特征和质量转移机制在不同的电解质度下
Mengsha Wang1, Qiang Xu1, Tengfei Nie1
1State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China. qiang.xu@mail.xjtu.edu.cn.
Physical chemistry chemical physics : PCCP
|October 17, 2023
概括
在光电化学水分裂中调节电解质度会影响泡动力学和质量转移. 高度降低了泡的大小和频率,提高了整体效率.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 光阳极上的泡阻碍了光电化学水分裂效率.
- 了解泡生长动力学和质量转移对于优化反应至关重要.
研究的目的:
- 研究电解质度对氧气泡生长和TiO2光电极上的质量转移的影响.
- 开发一个泡覆盖方程和分析质量转移系数.
主要方法:
- 采用了一种结合电化学工作站和高速显微镜的实验系统.
- 在恒定电压和电流条件下研究了泡生长动力学和质量转移.
- 分析了各种硫酸 (Na2SO4) 电解质度 (0.1-2.0 M) 的数据.
主要成果:
- 电解质度的增加减少了泡脱落的直径和频率.
- 提出了一个泡覆盖方程,将光电流和泡半径联系起来.
- 平均气泡覆盖率和气体演变效率随着度的增加而下降.
- 计算了质量转移系数;总质量转移随着度的增加而增加.
- 单相自然对流在气泡诱导的对流上占主导地位.
结论:
- 电解质度是控制泡行为和质量转移的关键参数.
- 优化电解质度可以增强光电化学水分裂中的气液质量转移.
- 质量转移系数在泡演变过程中发生变化,在初始阶段的价值较高.
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