title: Crystallographic orientation and electrode nature are key factors for electric current generation by Geobacter sulfurreducens.
abstract: We have investigated the influence of electrode material and crystallographic structure on electron transfer and biofilm formation of Geobacter sulfurreducens. Single-crystal gold-Au(110), Au(111), Au(210)-and platinum-Pt(100), Pt(110), Pt(111), Pt(210)-electrodes were tested and compared to graphite rods. G. sulfurreducens electrochemically interacts with all these materials with different attachment kinetics and final current production, although redox species involved in the electron transfer to the anode are virtually the same in all cases. Initial bacterial colonization was fastest on graphite up to the monolayer level, whereas gold electrodes led to higher final current densities. Crystal geometry was shown to have an important influence, with Au(210) sustaining a current density of up to 1442±101μAcm(-2) at the steady state, over Au(111) with 961±94μAcm(-2) and Au(110) with 944±89μAcm(-2). On the other hand, the platinum electrodes displayed the lowest performances, including Pt(210). Our results indicate that both crystal geometry and electrode material are key parameters for the efficient interaction of bacteria with the substrate and should be considered for the design of novel materials and microbial devices to optimize energy production.
authors.affiliation: Instituto Universitario de Electroquímica, Universidad de Alicante, Apdo. 99, Alicante E-03080, Spain. Electronic address: bmaestro35@gmail.es.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Maestro
authors.affiliation: Instituto Universitario de Electroquímica, Universidad de Alicante, Apdo. 99, Alicante E-03080, Spain. Electronic address: juanmanuel.ortiz1@fcc.es.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Ortiz
authors.affiliation: Área de electroquímica y corrosión, INTEMA (CONICET), Juan B. Justo 4302, B7608FDQ Mar del Plata, Argentina. Electronic address: germans@fi.mdp.edu.ar.
authors.forename: Germán
authors.initials: G
authors.lastname: Schrott
authors.affiliation: Área de electroquímica y corrosión, INTEMA (CONICET), Juan B. Justo 4302, B7608FDQ Mar del Plata, Argentina. Electronic address: jbusalme@fi.mdp.edu.ar.
authors.forename: Juan P
authors.initials: JP
authors.lastname: Busalmen
authors.affiliation: Instituto Universitario de Electroquímica, Universidad de Alicante, Apdo. 99, Alicante E-03080, Spain. Electronic address: clicvic@gmail.com.
authors.forename: Víctor
authors.initials: V
authors.lastname: Climent
authors.affiliation: Instituto Universitario de Electroquímica, Universidad de Alicante, Apdo. 99, Alicante E-03080, Spain. Electronic address: juan.feliu@ua.es.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Feliu
mesh_terms: D001674:Bioelectric Energy Sources; D018441:Biofilms / Q000254:growth & development*; D003461:Crystallography; D004560:Electricity; D055664:Electrochemical Techniques; D004566:Electrodes; D004579:Electron Transport; D045302:Geobacter / Q000254:growth & development*; D006046:Gold / Q000737:chemistry*; D018613:Microscopy, Confocal; D010984:Platinum / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D010984:Platinum; D006046:Gold
keywords: Biofilm; Cytochrome; Electron transport; Geobacter sulfurreducens; Single-crystal electrode