▎ 摘　　要

Single or a-few-atoms-thick sheets of graphene and graphene oxide (GO) exhibit a range of unique mechanical, optical, thermal, and electrical properties. While these properties have been extensively studied, research into the magnetics of graphene and GO systems is still in its early stages. A number of theoretical studies, which have yet to be verified experimentally, predict that various types of magnetism can be induced in otherwise diamagnetic carbon systems through (1) the introduction of defects in conjugated carbon networks (e.g., vacancies and " covalently bonded functional groups that are abundantly present in GO), (2,) the substitution of heteroatoms, and (3) edge effects. Although pristine graphene shows in many respects some of the most interesting features, unlike GO, it is difficult to produce pristine graphene in sufficient quantities to characterize or harvest its magnetic properties for real-world applications. In this study, we examine derivatives of graphene and describe an approach to induce a defect-based frustrated magnetic (spin-glass) phase in GO powders using a rather simple chemical process of surface modification by sodium sulfate (SS). Magnetization as a function of applied field (M-H loops) and the temperature dependence of magnetization in zero and nonzero field-cooling experiments show behavior that is typical for superparamagnets and frustrated magnetic systems such as spin glasses. Characterization of the magnetic properties paired with XPS and Raman spectroscopy reveal the nature of the chemical bonds and suggest that the exposure of paramagnetic GO to SS leads to the development of magnetic sites across the GO surface that form spin-glass-like phases similar to other spin-glass phases in highly disordered magnetic materials.