title: One-step sonochemical synthesis of a graphene oxide-manganese oxide nanocomposite for catalytic glycolysis of poly(ethylene terephthalate).
abstract: Ultrasound-assisted synthesis of a graphene oxide (GO)-manganese oxide nanocomposite (GO-Mn(3)O(4)) was conducted without further modification of GO or employing secondary materials. With the GO nanoplate as a support, potassium permanganate oxidizes the carbon atoms in the GO support and gets reduced to Mn(3)O(4). An intensive ultrasound method could reduce the number of reaction steps and temperature, enhance the reaction rate and furthermore achieve a Mn(3)O(4) phase. The composite was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The coverage and crystallinity of Mn(3)O(4) were controlled by changing the ratio of permanganate to GO dispersion. The synthesized nanocomposite was used as a catalyst for poly(ethylene terephthalate) (PET) depolymerization into its monomer, bis(2-hydroxylethyl) terephthalate (BHET). The highest monomer yield of 96.4% was obtained with the nanocomposite containing the lowest amount of Mn(3)O(4), while PET glycolysis with the Mn(3)O(4) without GO yielded 82.7% BHET.
authors.affiliation: Center for Nanobio Integration & Convergence Engineering, National Nanofab Center, 291 Daehak-ro, Yuseong-gu, Daejeon 305-806, Republic of Korea. tjpark@nnfc.re.kr
authors.forename: Gle
authors.initials: G
authors.lastname: Park
authors.forename: Leian
authors.initials: L
authors.lastname: Bartolome
authors.forename: Kyoung G
authors.initials: KG
authors.lastname: Lee
authors.forename: Seok Jae
authors.initials: SJ
authors.lastname: Lee
authors.forename: Do Hyun
authors.initials: DH
authors.lastname: Kim
authors.forename: Tae Jung
authors.initials: TJ
authors.lastname: Park
mesh_terms: D002384:Catalysis; D006019:Glycolysis; D006108:Graphite / Q000737:chemistry*; D017895:Manganese Compounds / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry*; D011093:Polyethylene Terephthalates / Q000737:chemistry*
chemical_list: D017895:Manganese Compounds; D010087:Oxides; D011093:Polyethylene Terephthalates; C048856:permanganic acid; C027424:manganese oxide; D006108:Graphite