▎ 摘　　要

NOVELTY - The method involves etching graphene, while functionalizing the etched graphene and attaching metal oxide nanoparticles to the functionalized graphene to form a device. The device is exposed to a fuel in the gas or liquid phase. A change in conductivity is detected when sulfur is present in the fuel, and recovering the device for future use. The graphene is etched to form a mesa structure comprising horizontal or vertical strips. The etched graphene is functionalized and, metal oxide nanoparticles are attached to the functionalized graphene, which has ultra violet activated chemical functionalization of graphene. USE - Method for parts per billion level in-line detection of sulfur in fuel cells for use in military applications, such as silent camp and silent watch operations. Uses include but are not limited to unmanned aerial vehicles, unmanned ground vehicles, solders portable power, as well as for operation on submarines and ships. ADVANTAGE - The method for parts per billion level in-line detection of sulfur in fuel cells ensures low noise and heat signatures, lower weight, and long life time, which is suitable for military operations, and provides exceptional physicochemical properties including high specific surface area, high carrier mobilities, and extremely low noise characteristics. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a parts per billion level in-line sulfur detector for gas and liquid phase fuels. DESCRIPTION OF DRAWING(S) - The drawing shows a scanning electron microscopy images of graphene films functionalized with indium tin oxide, ferric oxide, zinc oxide, and copper oxide nanoparticles.