使用纳米结构的α--氧化物作为电催化剂进行有效的水氧化
Minrui Gao1, Wenchao Sheng, Zhongbin Zhuang
1Department of Chemical and Biomolecular Engineering, Center for Catalytic Science and Technology, University of Delaware , Newark, Delaware 19716, United States.
Journal of the American Chemical Society
|April 26, 2014
概括
这项研究引入了α-Ni(OH) 2纳米晶体,作为水分裂中氧化演化反应 (OER) 的高度活性和稳定的电催化剂. 这种具有成本效益的催化剂显示了替代RuO2等昂贵替代品的潜力,以有效地生产燃料.
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
- 可再生能源是可再生能源的来源.
背景情况:
- 电化学分水为储存可再生能源作为燃料提供了一种清洁的方法.
- 氧化演化反应 (OER) 是水电解中的瓶,原因是动力学缓慢.
- 开发高效,稳定和具有成本效益的OER电催化剂仍然是一个重大挑战.
研究的目的:
- 合成和评估alpha-Ni(OH) 2纳米晶体作为氧化演化反应 (OER) 的电催化剂.
- 为了比较alpha-Ni(OH) 2与RuO2和其他氧化物相等最先进的催化剂的性能和稳定性.
- 为了证明α-Ni(OH) 2作为昂贵贵金属催化剂的可行替代品的潜力.
主要方法:
- 简单的合成α-Ni(OH) 2纳米晶体.
- 在性介质中OER性能的电化学表征,包括超电位和Tafel斜率测量.
- 在恶劣的OER循环条件下进行耐用性测试.
- 与β-Ni(OH) 2相进行比较研究.
主要成果:
- 高纳米结构的alpha-Ni(OH) 2表现出极好的OER活性,在0.331V的低超电位下达到10mA cm(-2).
- 催化剂显示出大约42mV/十年的小Tafel斜率,表明有效的OER动力学.
- 在长时间的OER循环中,alpha-Ni(OH) 2与RuO2相比显示出更高的耐用性和稳定性.
- 实验性比较证实alpha-Ni(OH) 2的催化效率优于β-Ni(OH) 2.
结论:
- 简单的合成α-Ni(OH) 2纳米晶体产生一个高度活跃和稳定的电催化剂,用于氧气演化反应.
- 阿尔法- (OH) 2 是一种有希望的,具有成本效益的替代品,可以替代昂贵的贵金属催化剂 (例如,RuO2,IrO2) 用于通过水分裂大规模生产.
- 这些发现为开发使用地球上丰富的材料的强大和高效的OER电催化剂铺平了道路.
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