High performance of electrosprayed graphene oxide/TiO2/Ce-TiO2 photoanodes for photoelectrocatalytic inactivation of S. aureus

Microbial contamination is a challenging concern due to the health threat caused by infections. Therefore, the development of efficient antimicrobial materials and processes is a crucial need for disinfecting water and surfaces. In this study, electrospray was used to prepare composite photoanodes f...

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Detalles Bibliográficos
Autores: Valenzuela, Laura, Faraldos, Marisol, Bahamonde, A., Rosal, Roberto
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2021
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/365520
Acceso en línea:http://hdl.handle.net/10261/365520
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85114801288&doi=10.1016%2fj.electacta.2021.139203&partnerID=40&md5=51d547feed1b8024420792e869ed6abc
Access Level:acceso abierto
Palabra clave:Cerium
Electrospray
Graphene oxide
Photoelectrocatalytic disinfection
Titanium dioxide
Anodes
Bacteria
Cerium oxide
Disinfection
Electrocatalysis
Graphene
Health risks
TiO2 nanoparticles
Electrosprays
Graphene oxides
Microbial contamination
Performance
Photo-anodes
Photo-electrocatalysis
S. aureus
Photoelectrocatalysis
Descripción
Sumario:Microbial contamination is a challenging concern due to the health threat caused by infections. Therefore, the development of efficient antimicrobial materials and processes is a crucial need for disinfecting water and surfaces. In this study, electrospray was used to prepare composite photoanodes for photoelectrodisinfection. Titanium dioxide (TiO2) and cerium-doped titanium dioxide (Ce-TiO2) composites with Graphene Oxide (GO) were electrosprayed onto graphite paper to create homogeneous coatings of uniformly distributed nanoparticle aggregates with a layer thickness of 1.0–1.5 μm. The photoanodes were irradiated using 365 nm LED light with irradiance representing a conservative estimation of the UVA component of solar light. The external potential for electrocatalysis (dark) and photoelectrocatalysis was set at + 0.6 V. The disinfection performance was assessed using anodes pre-exposed for 20 h in the darkness to exponentially growing cultures of Staphylococcus aureus. The highest antimicrobial activity was obtained for Ce-TiO2/GO anodes, which led to a 3-log reduction (99.9%) in the number of culturable cells after only 24 min of irradiation. The highest current density was also obtained for the same material and attributed to a better separation of charge carriers. Cell impairment was attributed to the overproduction of intracellular reactive oxygen species (ROS), which was higher in photoelectrocatalysis than in photocatalysis and electrocatalysis, with anodes performing in the following order: Ce-TiO2/GO > Ce-TiO2 > TiO2/GO > TiO2. The photoanodes exhibited steady photocurrent response, good photostability, and could be kept essentially clean from biofilms and colonizing bacteria. © 2021