Mechanistic Understanding of the Use of Single-Atom and Nanocluster Catalysts for Syngas Production via Partial Oxidation of Methane.

Single-atom and nanocluster catalysts presenting potent catalytic activity and excellent stability are used in high-temperature applications such as in structural composites, electrical devices, and catalytic chemical reactions. Recently, more attention has been drawn to application of these materials in clean fuel processing based on oxidation in terms of recovery and purification. The most popular media for catalytic oxidation reactions include gas phases, pure organic liquid phases, and aqueous solutions. It has been proven from the literature that catalysts are frequently selected as the finest in regulating organic wastewater, solar energy utilization, and environmental treatment applications in most catalytic oxidation of methane vis-à-vis photons and in environmental treatment applications. Single-atom and nanocluster catalysts have been engineered and applied in catalytic oxidations considering metal-support interactions and mechanisms facilitating catalytic deactivation. In this review, the present improvements on engineering single-atom and nano-catalysts are discussed. In detail, we summarize structure modification strategies, catalytic mechanisms, methods of synthesis, and application of single-atom and nano-catalysts for partial oxidation of methane (POM). We also present the catalytic performance of various atoms in the POM reaction. Full knowledge of the use of remarkable POM vis-à-vis the excellent structure is revealed. Based on the review conducted on single-atom and nanoclustered catalysts, we conclude their viability for POM reactions; however, the catalyst design must be carefully considered not only for isolating the individual influences from the active metal and support but also for incorporating the interactions of these components.