Nd:YAG laser ablation of micro-crystalline graphite in a water suspension

The aim of this work was to obtain graphene-like phases (defected graphene, graphene oxide and reduced graphene oxide) as fine suspensions by applying pulsed laser ablation (PLA) of micro-crystalline graphite suspension in water medium. The fundamental (lambda = 1064 nm), second (lambda = 532 nm), third (lambda = 355 nm) and fourth harmonics (lambda = 266 nm) of a Nd:YAG laser system (15-ns pulse duration and 10-Hz pulse repetition rate) were used. The morphology of the particles was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Their phase composition and structure were explored by Raman and X-ray photoelectron spectroscopies, grazing incidence X-ray diffractometry (GIXRD) and TEM. The specimens were prepared by drop-casting on a glass substrate (for Raman and GIXRD studies) and on a standard TEM copper mesh for SEM and TEM examination.