title: Synergistic electrocatalytic effect of nanostructured mixed films formed by functionalised gold nanoparticles and bisphthalocyanines.
abstract: A synergistic electrocatalytic effect was observed in sensors where two electrocatalytic materials (functionalized gold nanoparticles and lutetium bisphthalocyanine) were co-deposited using the Langmuir-Blodgett technique. Films were prepared using a novel method where water soluble functionalised gold nanoparticles [(11-mercaptoundecyl)tetra(ethylene glycol)] (SAuNPs) were inserted in floating films of lutetium bisphthalocyanine (LuPc2) and dimethyldioctadecylammonium bromide (DODAB) as the amphiphilic matrix. The formation of stable and homogeneous mixed films was confirmed by π-A isotherms, BAM, UV-vis and Raman spectroscopy, as well as by SEM and TEM microscopy. The synergistic effect towards hydroquinone of the electrodes modified with LuPc2:DODAB/SAuNP was characterised by an increase in the intensity of the redox peaks and a reduction of the overpotential. This synergistic electrocatalytic effect arose from the interaction between the SAuNPs and the phthalocyanines that occur in the Langmuir-Blodgett films and from the high surface area provided by the nanostructured films. The sensitivity increased with the amount of LuPc2 and SAuNPs inserted in the films and limits of detection in the range of 10(-7)molL(-1) were attained.
authors.affiliation: Universidad de Valladolid, Department of Inorganic Chemistry, Engineers School, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Medina-Plaza
authors.affiliation: Universidad de Valladolid, Department of Inorganic Chemistry, Engineers School, Spain; Faculdade de Ciências e Tecnologia, UNESP Univ Estadual Paulista, 19060-900 Presidente Prudente, SP, Brazil.
authors.forename: L N
authors.initials: LN
authors.lastname: Furini
authors.affiliation: Faculdade de Ciências e Tecnologia, UNESP Univ Estadual Paulista, 19060-900 Presidente Prudente, SP, Brazil.
authors.forename: C J L
authors.initials: CJ
authors.lastname: Constantino
authors.affiliation: Universidad de Valladolid, Department of Condensed Matter Physics, Faculty of Sciences, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: de Saja
authors.affiliation: Universidad de Valladolid, Department of Inorganic Chemistry, Engineers School, Spain. Electronic address: mluz@eii.uva.es.
authors.forename: M L
authors.initials: ML
authors.lastname: Rodri Guez-Mendez
mesh_terms: D002384:Catalysis; D004563:Electrochemistry / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D054833:Isoindoles; D053768:Metal Nanoparticles / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012995:Solubility; D013499:Surface Properties
chemical_list: D007211:Indoles; D054833:Isoindoles; D000644:Quaternary Ammonium Compounds; C015831:dimethyldioctadecylammonium; D006046:Gold; C013647:phthalocyanine
keywords: Bisphthalocyanine; Gold nanoparticle; Hydroquinone; Langmuir–Blodgett; Sensor