在氧化物上电氧化氨:阶段,pH值和中毒
Inbal Offen-Polak1, Hilla Ayali Aviram1, Adan Hijaze1
1Schulich Faculty of Chemistry, The Grand Technion Energy Program, and the Resnick Sustainability Center for Catalysis, Technion - Israel Institute of Technology, Technion City, 3200003 Haifa, Israel. eisenberg@technion.ac.il.
Physical chemistry chemical physics : PCCP
|December 6, 2024
概括
氧化相,α-Ni(OH) 2和β-Ni(OH) 2,表现出不同的氨氧化反应 (AOR) 电催化. 无序的α-Ni(OH) 2更活跃,但易受氨中毒,影响能量转化.
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
- 催化剂是一种催化剂.
背景情况:
- 氧化是的经济有效替代品,用于氨氧化反应 (AOR) 电催化.
- 了解不同晶相 (α-Ni(OH) 2与β-Ni(OH) 2在AOR中的作用至关重要,但尚未研究.
研究的目的:
- 为了研究和比较晶体β-Ni(OH) 2和无序α-Ni(OH) 2的电催化活性,用于氨氧化反应.
- 分析氨度和pH对不同氧化相的性能的影响.
主要方法:
- 使用XRD,HRSEM,拉曼和FTIR进行β-Ni(OH) 2和α-Ni(OH) 2的合成和表征.
- 在一系列氨度 (0.01-2 M) 和pH值 (11-13) 的电催化活性评估.
- 在线质谱测量用于产品识别和浸泡实验以确认中毒效应.
主要成果:
- 两种α-Ni(OH) 2/γ-NiOOH和β-Ni(OH) 2/β-NiOOH电催化氨氧化到N2.
- α-Ni(OH) 2 / γ-NiOOH对表现出更高的电催化活性.
- 高度的氨 (>1M) 会导致表面中毒,减少NiOOH形成和AOR电流,特别是在α-Ni(OH) 2.
结论:
- 氧化的晶体相显著影响其对氨氧化的电催化性能.
- 失调的α-Ni(OH) 2显示出更高的活性,但容易发生不可逆转的氨中毒.
- 了解氧化相位行为对于设计高效的循环电催化剂至关重要.
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