All-Fiber Erbium-Doped Q-Switched Laser With Recycled Graphite Oxide

This work demonstrates a passively Q-Switched fiber laser employing graphite oxide as a saturable absorber, generating tunable microsecond pulses with kHz repetition rates, pulse energies of up to 15.54 nJ and the pulse-to-pulse timing jitter of 46.14 fs. The graphite oxide samples were obtained by recycling the graphite present in Li-ion batteries utilized in cell phone devices through a chemical separation and subsequent oxidation process. Sample characterization employing X-ray diffraction, solid-state nuclear magnetic resonance and Raman spectroscopy showed that the produced graphite oxide exhibited a homogeneously oxidized structure. These results indicate that applications in the physics of pulsed lasers can benefit from the recycling of lithium batteries, directing the process of discarding spent batteries.