posted on 2023-08-03, 15:36authored byBhavya Joshi, Ahmed M.E. Khalil, Tanveer A. Tabish, Fayyaz A. Memon, Hong Chang, Shaowei Zhang
Graphene oxide (GO) is a conventional yet vital precursor
for the
synthesis of porous graphene (PG). Several strong oxidizing agents
such as potassium permanganate and perchlorates are typically used
for oxidization of graphite. However, they expose toxic reactants/products
that harm the environment. Therefore, a greener approach is desperately
needed to oxidize and exfoliate graphite. This study reports for the
first time on successful oxidation of graphite by ferrate(VI) compounds
via an encapsulation approach. By further reducing GO prepared from
this near green route with vitamin C, PG anticipated by many highly
important and expanding areas such as water treatment could be readily
achieved. X-ray diffraction (XRD), Fourier transform infrared (FTIR)
and UV–vis spectroscopy, and scanning electronic microscopy
(SEM) along with energy-dispersive spectroscopy confirmed the high
yield of GO from the oxidation of graphite. Raman spectroscopy, XRD,
and TEM confirmed the formation of high-quality few-layered PG from
the reduction of as-prepared GO. The above results demonstrated the
practicality of using encapsulated ferrate(VI) compounds to realize
green oxidation of graphite and resolve the paradox about the oxidation
capability of ferrate(VI). To further illustrate its potential for
the removal of emerging and crucial contaminants from water, as-prepared
PG was further examined against the contaminants of methyl orange
(MeO) dye and ibuprofen (IBU). Taken together, the results revealed
that more than 90% removal efficiency could be achieved at a high
PG dosage against MeO and IBU. This ground-breaking greener approach
opens the door to risk-free, extensive graphene environmental applications.