在酸中捕获水氧化物,用于质子交换膜水电解
Ranit Ram1, Lu Xia1, Hind Benzidi2
1ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Barcelona, Spain.
概括
在水电解中,解层 tungstate 形成了高度活跃和耐用的氧化反应催化剂. 这一突破推动了无需贵金属的高效燃料生产.
科学领域:
- 电化学
- 材料科学
- 催化剂
背景情况:
- 氧化演化反应 (OER) 对水电解至关重要,但耗费大量能量.
- 在质子交换膜水电解 (PEMWE) 中,通常需要贵金属催化剂来实现稳定的OER.
研究的目的:
- 开发一种非贵金属催化剂,使PEMWE具有高效和持久的OER.
- 研究 tungstate 分层在催化剂性能中的作用.
主要方法:
- 用 tungstate 分层,以创建富有缺陷的结构.
- 在PEMWE系统中对分层催化剂进行电化学测试.
- 在工业条件下 (80°C) 分析催化剂的稳定性和活性.
主要成果:
- 解层酸催化剂具有很高的活性和耐用性.
- 在2V时达到较低的超电位和1.8A/cm2的电流密度.
- 在工业条件下在1.77V下600小时稳定运行.
- 与传统催化剂相比, 催化剂的活性提高了三倍.
结论:
- 在晶格缺陷处, tungstate 的分层有效地稳定了氧化物和水氧化物网络.
- 这种方法为开发具有成本效益和高性能的水电解催化剂提供了有希望的途径.
- 可以有效地生产和太阳能燃料.
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