Free Energies of Catalytic Species Adsorbed to Pt(111) Surfaces under Liquid Solvent Calculated Using Classical and Quantum Approaches
Free Energies of Catalytic Species Adsorbed to Pt(111) Surfaces under Liquid Solvent Calculated Using Classical and Quantum Approaches
复制标题
使用经典和量子方法计算液体溶剂下吸附到 Pt(111) 表面的催化物质的自由能
DOI：
10.1021/acs.jcim.9b00089
复制
发表时间：
2019
影响因子：
5.6
通讯作者：
Getman, Rachel B.
中科院分区：
文献类型：
--
作者：
Zhang, Xiaohong;DeFever, Ryan S.;Sarupria, Sapna;Getman, Rachel B.
溶剂在液相多相催化中起着重要的作用，然而，用于计算固-液界面处催化现象的自由能的方法并不完善。例如，溶剂分子改变催化物质的能量并参与催化反应，因此可以显著影响催化性能。在这项工作中，我们开始建立计算这种现象的自由能的方法，具体地说，通过采用显式溶剂化方法使用多尺度采样（MSS）的方法。这种MSS方法结合了经典的分子动力学与密度泛函理论。我们用它来计算催化物种的溶剂化自由能，特别是吸附在Pt（111）表面的NH*，NH 2 *，CO*，COH*，CH 2 OH *，和C 3 H 7 O 3 * 在水相和在H2 O/CH 3 OH混合溶剂。我们比较我们的计算值与类似的值从隐式溶剂化的验证和识别的情况下，隐式溶剂化是足够的，而显式溶剂需要计算吸附自由能。我们的研究结果表明，明确的量子为基础的方法时，需要吸附形成化学键和/或强氢键与水溶剂。使用MSS，我们进一步将计算出的自由能分为能量和熵的贡献，以了解每一个如何影响自由能。我们发现，表现出较强的能量的吸附物也表现出较强的和负的熵，我们把这种关系的吸附物和溶剂分子之间的氢键，这提供了一个大的能量贡献，但降低了整体流动性的溶剂。
Solvent plays an important role in liquid phase heterogeneous catalysis; however, methods for calculating the free energies of catalytic phenomena at the solid–liquid interface are not well-established. For example, solvent molecules alter the energies of catalytic species and participate in catalytic reactions and can thus significantly influence catalytic performance. In this work, we begin to establish methods for calculating the free energies of such phenomena, specifically, by employing an explicit solvation method using a multiscale sampling (MSS) approach. This MSS approach combines classical molecular dynamics with density functional theory. We use it to calculate the free energies of solvation of catalytic species, specifically adsorbed NH*, NH2*, CO*, COH*, CH2OH*, and C3H7O3* on Pt(111) surfaces under aqueous phase and under a mixed H2O/CH3OH solvent. We compare our calculated values with analogous values from implicit solvation for validation and to identify situations where implicit solvation is sufficient versus where explicit solvent is needed to compute adsorbate free energies. Our results indicate that explicit quantum-based methods are needed when adsorbates form chemical bonds and/or strong hydrogen bonds with H2O solvent. Using MSS, we further separate the calculated free energies into energetic and entropic contributions in order to understand how each influences the free energy. We find that adsorbates that exhibit strong energies also exhibit strong and negative entropies, and we attribute this relationship to hydrogen bonding between the adsorbates and the solvent molecules, which provides a large energetic contribution but reduces the overall mobility of the solvent.
登录
查看更多内容
影响因子：
3.9
作者：
Tianjun Xie;Cameron J. Bodenschatz;Rachel B. Getman
通讯作者：
Tianjun Xie;Cameron J. Bodenschatz;Rachel B. Getman
室温下 Barstar 展开结构周围水的微观动力学。
影响因子：
4.4
作者：
S. Pal;K. Chakraborty;Prabir Khatua;S. Bandyopadhyay
通讯作者：
S. Bandyopadhyay
使用速率控制程度来改善 MOF 封装催化剂模型的选择性正丁烷氧化：空间约束的 Ag3Pd(111)。
影响因子：
3.4
作者：
Sean T. Dix;Joseph K. Scott;Rachel B. Getman;C. Campbell
通讯作者：
C. Campbell
影响因子：
15
作者：
Greeley, J;Mavrikakis, M
通讯作者：
Mavrikakis, M