SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University, 450 Serra Mall Stanford, California 94305, USA.
Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
Nat Mater. 2017 Feb;16(2):225-229. doi: 10.1038/nmat4760. Epub 2016 Oct 10.
While the search for catalysts capable of directly converting methane to higher value commodity chemicals and liquid fuels has been active for over a century, a viable industrial process for selective methane activation has yet to be developed. Electronic structure calculations are playing an increasingly relevant role in this search, but large-scale materials screening efforts are hindered by computationally expensive transition state barrier calculations. The purpose of the present letter is twofold. First, we show that, for the wide range of catalysts that proceed via a radical intermediate, a unifying framework for predicting C-H activation barriers using a single universal descriptor can be established. Second, we combine this scaling approach with a thermodynamic analysis of active site formation to provide a map of methane activation rates. Our model successfully rationalizes the available empirical data and lays the foundation for future catalyst design strategies that transcend different catalyst classes.
虽然寻找能够直接将甲烷转化为高附加值商品化学品和液体燃料的催化剂的研究已经活跃了一个多世纪，但选择性甲烷活化的可行工业工艺尚未开发出来。电子结构计算在这一研究中发挥着越来越重要的作用，但由于过渡态势垒计算计算成本高昂，大规模的材料筛选工作受到了阻碍。本函的目的有二。首先，我们表明，对于通过自由基中间体进行的广泛催化剂，可以使用单个通用描述符为 C-H 活化势垒建立统一的预测框架。其次，我们将这种缩放方法与活性位点形成的热力学分析相结合，提供了甲烷活化速率的图谱。我们的模型成功地合理化了现有的经验数据，并为未来超越不同催化剂类别的催化剂设计策略奠定了基础。
