水的自我解离对纳米环境不敏感
Solana Di Pino1,2, Yamila A Perez Sirkin1, Uriel N Morzan2
1Departamento de Química Inorgánica, Analítica y Química Física/INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, C1428EHA, Argentina.
Angewandte Chemie (International ed. in English)
|June 28, 2023
概括
即使在纳米尺度下,水解离能量也保持在12个分子或2纳米孔中. 这一发现阐明了水在界面和气溶等封闭环境中的自电离和反应性.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 材料科学 材料科学 材料科学
背景情况:
- 纳米封闭对水解离和反应性的影响尚不清楚,导致实验和模拟结果相互矛盾.
- 了解界面,毛孔和气溶中的水性化学对于各种科学学科至关重要.
研究的目的:
- 在纳米限制下研究水解离的能量.
- 为了确定散装水分离行为维持的最小长度尺度.
- 为了澄清热力学和水自电离的机制在封闭的环境中.
主要方法:
- 使用ab initio模拟来建模水分离.
- 计算了水自电离的能量和自由能量概况.
- 在分子聚合物和纳米孔状结构上进行了模拟.
主要成果:
- 大量水分离的能量在很大程度上保持不变,直到纳米尺度 (约. 12个分子或<2nm孔).
- 在散装,纳米滴和纳米孔 (没有强烈的界面相互作用) 中,O-H键破裂的自由能量屏障保持不变.
- 纳米系统中的解离自由能量配置模仿了散装液体的行为.
结论:
- 在非常小的长度尺度上,纳米封闭不会显著改变水分离的能量.
- 水自电离的基本机制和热力学在不同尺度上都是强大的.
- 这项工作提供了对水解离的最终理解,影响了对界面的反应性和自我电离性的研究.
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