Cheng Dongfang, Zhao Zhi-Jian, Zhang Gong, Yang Piaoping, Li Lulu, Gao Hui, Liu Sihang, Chang Xin, Chen Sai, Wang Tuo, Ozin Geoffrey A, Liu Zhipan, Gong Jinlong
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, 300072, Tianjin, China.
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), 300072, Tianjin, China.
Nat Commun. 2021 Jan 15;12(1):395. doi: 10.1038/s41467-020-20615-0.
The active sites for CO electroreduction (COR) to multi-carbon (C) products over oxide-derived copper (OD-Cu) catalysts are under long-term intense debate. This paper describes the atomic structure motifs for product-specific active sites on OD-Cu catalysts in COR. Herein, we describe realistic OD-Cu surface models by simulating the oxide-derived process via the molecular dynamic simulation with neural network (NN) potential. After the analysis of over 150 surface sites through NN potential based high-throughput testing, coupled with density functional theory calculations, three square-like sites for C-C coupling are identified. Among them, Σ3 grain boundary like planar-square sites and convex-square sites are responsible for ethylene production while step-square sites, i.e. n(111) × (100), favor alcohols generation, due to the geometric effect for stabilizing acetaldehyde intermediates and destabilizing Cu-O interactions, which are quantitatively demonstrated by combined theoretical and experimental results. This finding provides fundamental insights into the origin of activity and selectivity over Cu-based catalysts and illustrates the value of our research framework in identifying active sites for complex heterogeneous catalysts.
在氧化物衍生铜（OD-Cu）催化剂上，将CO电还原（COR）为多碳（C）产物的活性位点长期以来一直存在激烈争论。本文描述了COR中OD-Cu催化剂上产物特异性活性位点的原子结构基序。在此，我们通过使用神经网络（NN）势的分子动力学模拟来模拟氧化物衍生过程，从而描述了真实的OD-Cu表面模型。通过基于NN势的高通量测试对150多个表面位点进行分析，并结合密度泛函理论计算，确定了三个用于C-C偶联的方形位点。其中，Σ3晶界状平面方形位点和凸方形位点负责乙烯生成，而台阶方形位点，即n(111)×(100)，有利于醇的生成，这是由于稳定乙醛中间体和破坏Cu-O相互作用的几何效应，理论和实验结果相结合对其进行了定量证明。这一发现为基于铜的催化剂的活性和选择性起源提供了基本见解，并说明了我们的研究框架在识别复杂多相催化剂活性位点方面的价值。
