在酸性氧的演化过程中,通过电子储稳定高度活跃的Ru站点
Jiayan Wu1, Zhongjie Qiu1, Jiaxi Zhang1
1Guangdong Provincial Key Laboratory of Fuel Cell Technology, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, China.
Molecules (Basel, Switzerland)
|February 24, 2024
概括
这项研究通过结合高价值金属来稳定二氧化卢 (RuO2) 催化剂的氧化演化反应. (Re) 兴奋剂增强了活性和耐久性,为水电解提供了具有成本效益的解决方案.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 质子交换膜水电解受缓慢的氧化演化反应 (OER) 动力学限制.
- 二氧化卢 (RuO2) 是一种潜在的阳极催化剂,可以替代二氧化 (IrO2),因为它的活性和成本较低.
- 在酸性OER条件下RuO2溶解会损害其长期稳定性.
研究的目的:
- 通过加入高价值金属,制定稳定酸性OER中的RuO2的策略.
- 为了研究剂的离子电子阴性对RuO2稳定性和OER性能的影响.
- 提高RuO2基催化剂的活性和耐用性,以实现高效的水电解.
主要方法:
- 使用盐方法合成高价值金属替代的RuO2.
- 电化学表征以评估OER活动和稳定性.
- 表面分析以确定Ru4+/Ru3+物种的比例,并了解剂的作用.
主要成果:
- 高表面Ru4+含量与内在的OER活动正相关.
- 在Ru4+/Ru3+比率和dopant离子电负性之间存在线性关系.
- 被 (Re) 的Re0.1Ru0.9O2表现出较低的超电位 (199 mV在10 mA cm-2) 和特殊的稳定性 (>300小时在10 mA cm-2,>25小时在100 mA cm-2).
结论:
- 加入高价值金属,特别是Re,有效地稳定了RuO2的酸性OER.
- Re 作为电子储库,减轻 Ru 的过氧化,增强催化剂的耐用性.
- 这项工作提出了一种可行的策略,用于稳定具有成本效益的Ru基催化剂,用于酸性OER应用.
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