Concepts of Computational Approach to Explore Heterogeneous Catalysts for Direct Methane Conversion

Abstract

The nonoxidative coupling of methane has attracted much attention because it yields two useful products: ethane and hydrogen. However, low conversion at low temperatures and carbon deposition at high temperatures are considered problematic. In this Concept article, a solution to these problems is presented. On the basis of the reaction enthalpy for the initial C−H bond cleavage of methane and the energy difference between C1 species (CH3 and CH) on the catalyst surface, a catalyst search guideline is provided to suppress carbon deposition while keeping the conversion rate as high as possible. Alloys are considered catalyst candidates. Few materials satisfy both of these requirements simultaneously; however, several alloys, including MgPt, are shown to be promising. The results of validation experiments for the catalytic performance of MgPt are also discussed.

Recent Advances in the Use of Controlled Nanocatalysts in Methane Conversion Reactions

“…Furthermore, the study revealed how nanoparticle size alters the ratio between these exposed surfaces and their respective significance in catalytic properties. The activity dependency on nanoparticle size was found to be closely linked to surface characteristics [132,133]. At smaller particle sizes, the dominance of the M(211) surface exposure was noted, whereas larger particles saw increasing contributions from M (111) and M(100).…”

“…However, the en-ergetics favored M(211) over M (111), and the activity of M(100) was limited by surface site blockage. Consequently, larger particles exhibited reduced activity due to the lower activity of M(100) and M (111) surfaces when compared to M(211) [129][130][131][132][133]. In terms of metal-dependent activity, the study found that Rh exhibited the highest activity, followed by Ni, and then Pd and Pt, which showed similar levels of activity.…”

Exploring Metal Nanocluster Catalysts for Ammonia Synthesis Using Informatics Methods: A Concerted Effort of Bayesian Optimization, Swarm Intelligence, and First-Principles Computation

“…A field called catalytic informatics is emerging. Several review and concept articles have been written on this field. − Indeed, a wide variety of informatics methods are becoming available to aid in catalyst development.…”