H2O2 用分子电催化剂进行合成,使得使用气体扩散电极在流电池中实现大量电流密度
Phebe H van Langevelde1, Nathalie E G Ligthart2, Pim G J van Duren1
1Leiden Institute of Chemistry, Leiden University, 2300 RA Leiden, The Netherlands.
概括
用气体扩散电极 (GDE) 测试了用于产生过氧化 (H2O2) 的两电子氧降解反应 (ORR) 的分子催化剂. 这种配置显著增强了催化电流,与旋转盘电极 (RDE) 相比,揭示了新的选择性趋势.
科学领域:
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 产生过氧化 (H2O2) 的两电子氧降解反应 (ORR) 的分子催化剂具有显著的兴趣.
- 之前的研究仅限于旋转盘电极 (RDE) 设置,阻碍了对工业相关配置的评估.
- 在RDE的质量运输限制限制了对分子ORR催化剂的真实催化电流的评估.
研究的目的:
- 为了评估一个基于铜的分子ORR催化剂,Cu-(tmpa) 在气体扩散电极 (GDE) 电池配置中的性能.
- 在GDE设置中识别影响催化电流和H2O2生成的因素.
- 评估分子催化剂在工业相关反应堆配置中的潜力.
主要方法:
- 使用易于组装的GDE细胞来测试Cu- ((tmpa) 催化剂.
- 研究了缓冲度,催化剂度和GDE组成对催化电流的影响.
- 在GDE流量单元中长时间运行Cu-(tmpa) 催化剂.
主要成果:
- 在GDE流细胞中,Cu-(tmpa) 在多个小时内显示持续生成H2O2.
- 在-20 mA/cm2下,实现了50%的法拉代效率和0.11 mmol cm−2 h−1的生产率.
- 与RDE相比,GDE配置的电流密度增加了近10倍,随着变化的选择性趋势,在更高的电流下有利于H2O2.
结论:
- 该GDE设置使得分子ORR催化剂潜力的全面评估能够超出理想的RDE条件.
- - ((tmpa) 在GDE配置中显示出作为H2O2生成催化剂的希望,适合实际应用.
- 分子催化剂的精确定义的活性位点可以有效地用于新兴的H2O2生产技术.
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