通过机器学习解释非金属表面的Ni2P的化学压力驱动增强
Robert B Wexler1, John Mark P Martirez2, Andrew M Rappe1
1Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States.
Journal of the American Chemical Society
|March 20, 2018
概括
通过调节吸附,Ni2P催化剂的非金属注增强了演化反应 (HER) 的活性. 硫化,特别是优化了Ni3空洞部位的有效催化作用.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 酸 (Ni2P) 催化剂对演化反应 (HER) 有希望.
- 在Ni3空洞部位的强吸附限制了Ni2P的催化活性.
- 在适度的电化学条件下,Ni2P(0001) 表面终端是稳定的.
研究的目的:
- 研究表面非金属兴奋剂对Ni2P的HER活性的影响.
- 确定最佳的补充剂和度,以提高HER的性能.
- 了解在化Ni2P中控制HER的结构-活性关系.
主要方法:
- 用密度功能理论 (DFT) 的计算来建模合的Ni2P表面.
- 对各种非金属剂计算了吸附的自由能量.
- 一个规范的随机森林机器学习算法被用来确定描述者的重要性.
主要成果:
- 发现2p非金属和较重的石化物几乎可以实现热中性吸附.
- 对表面的替代被确定为能量有利 (exergonic).
- 在中等度的硫注射导致吸附的自由能量为-0.11 eV,在未注表面显著改善 (-0.45 eV).
结论:
- 表面非金属注,尤其是硫等基,可以有效地增强Ni2P催化剂的HER活性.
- 尼-尼结合长度成为HER活性最关键的描述因素,表明剂通过化学压力效应影响反应性.
- 这些发现为设计更高效的生产电催化剂提供了途径.
更多相关视频
06:32A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
Published on: August 17, 2016
20.4K
12:18A Machine Learning Approach to Design an Efficient Selective Screening of Mild Cognitive Impairment
Published on: January 11, 2020
8.1K
相关概念视频
Types of Chemical Bonds
94.6K
Chemical bonding theories were pioneered by American chemist Gilbert N. Lewis. He developed a model called the Lewis model to explain the type and formation of different bonds. Chemical bonding is central to chemistry; it explains how atoms or ions bond together to form molecules. It explains why some bonds are strong and others are weak, or why one carbon bonds with two oxygens and not three; why water is H2O and not H4O.
94.6K
Hydrogen Bonds
134.5K
Hydrogen bonds are weak attractions between atoms that have formed other chemical bonds. One of these atoms is electronegative, like oxygen, and has a partial negative charge. The other is a hydrogen atom that has bonded with another electronegative atom and has a partial positive charge.
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared....
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared....
134.5K
Hydrogen Bonds
15.1K
A hydrogen bond is formed when a weakly positive hydrogen atom already bonded to one electronegative atom (for example, the oxygen in the water molecule) is attracted to another electronegative atom from another polar molecule, such as water (H2O), hydrogen fluoride (HF), or ammonia (NH3). The huge electronegativity difference between the H atom (2.1) and the atom to which it is bonded (4.0 for an F atom, 3.5 for an O atom, or 3.0 for an N atom), combined with the very small size of an H atom...
15.1K
Hydrostatic Pressure Force on a Plane Surface
1.5K
When a plane surface is submerged in a fluid, hydrostatic forces develop on the surface due to the fluid's pressure. For horizontal surfaces, the pressure exerted by the fluid is uniform because the depth remains constant. The resultant force is determined by the pressure at the given depth multiplied by the area of the surface, and it acts through the centroid of the surface. For vertical surfaces, the pressure varies with depth, increasing as the distance from the fluid's free surface...
1.5K
Hydrostatic Pressure Force on a Curved Surface
2.6K
Hydrostatic pressure on curved surfaces is a fundamental concept in fluid mechanics with broad applications in the civil engineering field. When fluid is in contact with a curved surface, as in a reservoir, dam, or storage tank, it exerts pressure that varies in magnitude and direction along the curved surface. To assess the total hydrostatic force exerted by the fluid on a curved structure, engineers typically isolate the fluid volume adjacent to the surface and analyze the forces acting on...
2.6K
Thermodynamics: Chemical Potential and Activity
1.8K
The effective concentration of a species in a solution can be expressed precisely in terms of its activity. Activity considers the effect of electrolytes present in the vicinity of the species of interest and depends on the ionic strength of the solution. The activity of a species is expressed as the product of molar concentration and the activity coefficient of the species.
The thermodynamic equilibrium constant is more accurately defined in terms of activity rather than concentration.
The thermodynamic equilibrium constant is more accurately defined in terms of activity rather than concentration.
1.8K
