title: In situ measurements of dissolved oxygen, pH and redox potential of biocathode microenvironments using microelectrodes.
abstract: Biofilms are the core component of bioelectrochemical systems (BESs). To understand the polarization effects on biocathode performance of BES, dissolved oxygen concentrations, pHs and oxidation-reduction potentials of biofilm microenvironments were determined in situ. The results showed that lower polarization potentials resulted in the generation of larger currents and higher pH values, as well as the consumption of more oxygen. Oxidation-reduction potentials of biofilms were mainly affected by polarization potentials of the electrode rather than the concentration of dissolved oxygen or pH value, and its changes in the potentials corresponded to the electric field distribution of the electrode surface. The results demonstrated that a sufficient supply of dissolved oxygen and pH control of the biocathode are necessary to obtain optimal performance of BESs; a lower polarization potential endowed microorganisms with a higher electrochemical activity.
authors.affiliation: Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, Fujian Province 361021, China.
authors.forename: Zejie
authors.initials: Z
authors.lastname: Wang
authors.forename: Huan
authors.initials: H
authors.lastname: Deng
authors.forename: Lihui
authors.initials: L
authors.lastname: Chen
authors.forename: Yong
authors.initials: Y
authors.lastname: Xiao
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
mesh_terms: D001674:Bioelectric Energy Sources / Q000382:microbiology*; D018441:Biofilms; D060833:Cellular Microenvironment; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D017404:In Situ Hybridization, Fluorescence; D018613:Microscopy, Confocal; D010084:Oxidation-Reduction; D010100:Oxygen / Q000032:analysis; D010101:Oxygen Consumption
chemical_list: D010100:Oxygen