title: Three-dimensional graphene networks as a new substrate for immobilization of laccase and dopamine and its application in glucose/O2 biofuel cell.
abstract: We report here three-dimensional graphene networks (3D-GNs) as a novel substrate for the immobilization of laccase (Lac) and dopamine (DA) and its application in glucose/O2 biofuel cell. 3D-GNs were synthesized with an Ni(2+)-exchange/KOH activation combination method using a 732-type sulfonic acid ion-exchange resin as the carbon precursor. The 3D-GNs exhibited an interconnected network structure and a high specific surface area. DA was noncovalently functionalized on the surface of 3D-GNs with 3,4,9,10-perylene tetracarboxylic acid (PTCA) as a bridge and used as a novel immobilized mediating system for Lac-based bioelectrocatalytic reduction of oxygen. The 3D-GNs-PTCA-DA nanocomposite modified glassy carbon electrode (GCE) showed stable and well-defined redox current peaks for the catechol/o-quinone redox couple. Due to the mediated electron transfer by the 3D-GNs-PTCA-DA nanocomposite, the Nafion/Lac/3D-GNs-PTCA-DA/GCE exhibited high catalytic activity for oxygen reduction. The 3D-GNs are proven to be a better substrate for Lac and its mediator immobilization than 2D graphene nanosheets (2D-GNs) due to the interconnected network structure and high specific surface area of 3D-GNs. A glucose/O2 fuel cell using Nafion/Lac/3D-GNs-PTCA-DA/GCE as the cathode and Nafion/glucose oxidase/ferrocence/3D-GNs/GCE as the anode can output a maximum power density of 112 μW cm(-2) and a short-circuit current density of 0.96 mA cm(-2). This work may be helpful for exploiting the popular 3D-GNs as an efficient electrode material for many other biotechnology applications.
authors.affiliation: Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University , Changsha 410081, China.
authors.forename: Yijia
authors.initials: Y
authors.lastname: Zhang
authors.forename: Mi
authors.initials: M
authors.lastname: Chu
authors.forename: Lu
authors.initials: L
authors.lastname: Yang
authors.forename: Yueming
authors.initials: Y
authors.lastname: Tan
authors.forename: Wenfang
authors.initials: W
authors.lastname: Deng
authors.forename: Ming
authors.initials: M
authors.lastname: Ma
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Su
authors.forename: Qingji
authors.initials: Q
authors.lastname: Xie
mesh_terms: D001674:Bioelectric Energy Sources; D004298:Dopamine / Q000378:metabolism*; D055664:Electrochemical Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005465:Fluorocarbon Polymers / Q000737:chemistry; D005947:Glucose / Q000032:analysis*; D006108:Graphite / Q000737:chemistry*; D042845:Laccase / Q000378:metabolism*; D008855:Microscopy, Electron, Scanning; D010100:Oxygen / Q000032:analysis*; D010569:Perylene / Q000031:analogs & derivatives; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013379:Substrate Specificity; D055454:Trametes / Q000201:enzymology; D014961:X-Ray Diffraction
chemical_list: C560550:3,4,9,10-perylene tetracarboxylic acid; D004800:Enzymes, Immobilized; D005465:Fluorocarbon Polymers; C040402:perfluorosulfonic acid; D010569:Perylene; D006108:Graphite; D042845:Laccase; D005947:Glucose; D010100:Oxygen; D004298:Dopamine