Kye So-Hwang, Park Hee Sun, Zhang Renqin, Yang Hee Jung, Lee Kyu Hyung, Suh Hoyoung, Kim Jin-Gyu, Kim Min Gyu, Hwang Gyeong S, Hur Nam Hwi
Department of Chemistry, Sogang University, Seoul 04107, South Korea.
McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
J Chem Phys. 2020 Feb 7;152(5):054715. doi: 10.1063/1.5135741.
Catalytic transformation of methane (CH) into methanol in a single step is a challenging issue for the utilization of CH. We present a direct method for converting CH into methanol with high selectivity over a Pt/CeO catalyst which contains ionic Pt species supported on a CeO nanoparticle. The Pt/CeO catalyst reproducibly yielded 6.27 mmol/g of Pt with a selectivity of over 95% at 300 °C when CH and CO are used as reactants, while the catalyst had a lower activity when using only CH without CO. Active lattice oxygen created on the Pt and CeO interface provides selective reaction pathways for the conversion of CH to methanol. Based on high-angle annular dark-field scanning transmission electron microscopy, x-ray photoelectron spectroscopy, x-ray absorption near-edge structure, extended x-ray absorption fine structure, catalytic studies, and density functional theory calculations, we propose a mechanistic pathway involving CH activation at the active site in the vicinity of Pt species.
将甲烷（CH₄）一步催化转化为甲醇是甲烷利用中的一个具有挑战性的问题。我们提出了一种直接方法，可在负载于CeO₂纳米颗粒上含有离子态Pt物种的Pt/CeO₂催化剂上，以高选择性将CH₄转化为甲醇。当使用CH₄和CO作为反应物时，Pt/CeO₂催化剂在300℃下可重复产生6.27 mmol/g的Pt，选择性超过95%，而仅使用CH₄而不使用CO时，该催化剂活性较低。在Pt和CeO₂界面上产生的活性晶格氧为CH₄转化为甲醇提供了选择性反应途径。基于高角度环形暗场扫描透射电子显微镜、X射线光电子能谱、X射线吸收近边结构、扩展X射线吸收精细结构、催化研究和密度泛函理论计算，我们提出了一种涉及在Pt物种附近的活性位点处CH₄活化的机理途径。
