从低度酸介质中有效的光化学蒸汽生成
Eva Jeníková1,2, Jaromír Vyhnanovský1,2, Karolína Hašlová1,2
1Institute of Analytical Chemistry of the Czech Academy of Sciences, Veveří 97, Brno 602 00, Czech Republic.
Analytical chemistry
|January 6, 2024
概括
光化学蒸汽生成 (PVG) 对于Ir,Ru和Re使用稀释酸 (HCOOH) 在流通光反应器中具有惊人的效率. 这种方法提供了比传统方法更高的效率,即使没有敏感剂.
科学领域:
- 分析化学 分析化学
- 摄影化学的使用.
- 频谱学是一种光谱学.
背景情况:
- 光化学蒸汽生成 (PVG) 是一种用于元素分析的技术.
- 传统的PVG通常需要高度的试剂,并且对某些元素的效率可能有限.
- 优化PVG条件对于提高分析灵敏度和适用性至关重要.
研究的目的:
- 为了研究PVG对各种元素的效率,使用稀释酸 (HCOOH) 介质.
- 探索不同度的HCOOH和添加敏感剂对PVG效率的影响.
- 确定在稀释介质中增强PVG的潜在机械因素.
主要方法:
- 使用在流量注入模式下运行的薄膜流通光反应器.
- 测试了稀释甲酸 (HCOOH) 度,包括大约0.01M,并将它们与传统的较高度 (1-20M) 进行了比较.
- 研究了酸盐 (HCOONa) 和金属离子敏化剂 (Cd2+,Co2+) 对Ru,Re和Ir的PVG效率的影响.
主要成果:
- 实现了惊人的高光伏效率,用于Ir (近20%),Ru (约. 0.06%),以及Re (大约0.06%),以及Re (大约0.06%). 0.06%) 在稀释的HCOOH (0.01 M) 中,没有敏感剂.
- 观察到Ru (9%) 和Re (1.5%) 的效率提高,其中0.005 M HCOONa.
- 添加Cd2+和CO2+敏感剂显著提高了PVG效率,达到17% (Ru),2.2% (Re) 和81% (Ir).
- 扩展研究发现了稀释HCOOH和酸 (CH3COOH) 中的Co,As,Se,Te和Bi的类似现象.
结论:
- 稀释的HCOOH介质,特别是在0.01M左右,可以为几个元素提供高效的PVG,特别是Ir,Ru和Re.
- 使用金属离子传感器进一步提高了PVG的效率,特别是在Ir.
- 虽然稀释介质对分析应用具有吸引力,但由于潜在较低的激素和水性电子度,稀释介质可能对溶解的气体和干扰物耐受性较低.
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