Percolating Metallic Structures Templated on Laser-deposited Carbon Nanofoams derived from Graphene Oxide: Applications in Humidity Sensing

ACS Applied Nano Materials 2018, 1(4), 1828-1835


Carbon nanofoam (CNF) is a low-density, high-surface-area material formed by aggregation
of amorphous carbon nanoparticles into porous nanostructures. We report the use of a pulsed infrared laser to prepare CNF from a graphene oxide (GO) target material. Electron microscopy shows that the films consist of dendritic strings which form web-like three-dimensional structures. The conductivity of these structures can be modified by using the CNF as a nanostructured scaffold for gold nanoparticles deposited by sputter coating, controllably increasing the conductivity by up to four orders of magnitude. The ability to measure the conductivity of the porous structures allows electrochemical measurements in the environment. Upon decreasing humidity, the pristine CNF exhibits an increase in resistance with a quick response and recovery time. By contrast, the gold-sputtered CNF …