Theoretical Investigation on Degradation Mechanism of Sarin over Graphene-Supported Single Atom Catalysts

The direct exposure of chemical warfare agents (CWAs) has always been detrimental to Soldiers on the battlefield, causing an estimated 1.3 million casualties during World War I alone. Of particular concern are nerve agents, including sarin, soman, and VX. Novel materials with specific functionalities are necessary to provide advanced protection through layered coatings or respirators to ensure the safety of Soldiers and untrained citizens alike. Thus, gaining a mechanistic understanding on the degradation pathways of CWAs over chemical catalysts is a crucial area of active research. In this work, we propose to study some of the notable chemical warfare agents frequently employed in the field, specifically gas-phase hydrolysis of sarin over the supported single atom catalysts (SACs). We seek to investigate both thermodynamic and kinetic aspects of degradation hydrolysis mechanisms over graphene-supported SACs and identify the key rate-determining steps, which can further be manipulated through the choice of metals and, potentially, supports. We found that a linear relationship can be drawn between the energy difference and the activation barrier of rate-determining step for degradation process.