title: Direct Solar Charging of an Organic-Inorganic, Stable, and Aqueous Alkaline Redox Flow Battery with a Hematite Photoanode.
abstract: The intermittent nature of the sunlight and its increasing contribution to electricity generation is fostering the energy storage research. Direct solar charging of an auspicious type of redox flow battery could make solar energy directly and efficiently dispatchable. The first solar aqueous alkaline redox flow battery using low cost and environmentally safe materials is demonstrated. The electrolytes consist of the redox couples ferrocyanide and anthraquinone-2,7-disulphonate in sodium hydroxide solution, yielding a standard cell potential of 0.74 V. Photovoltage enhancement strategies are demonstrated for the ferrocyanide-hematite junction by employing an annealing treatment and growing a layer of a conductive polyaniline polymer on the electrode surface, which decreases electron-hole recombination.
authors.affiliation: Department of Engineering, Aarhus University, Hangoevej 2, 8200, Aarhus, Denmark.
authors.forename: Kristina
authors.identifier: 0000-0001-7134-9718
authors.initials: K
authors.lastname: Wedege
authors.affiliation: LEPABE-Department of Engineering, University of Porto, Rua Dr. Roberto Frias S/N, P-4200-465, Porto, Portugal.
authors.forename: João
authors.identifier: 0000-0001-6035-0377
authors.initials: J
authors.lastname: Azevedo
authors.affiliation: Department of Engineering, Aarhus University, Hangoevej 2, 8200, Aarhus, Denmark.
authors.forename: Amirreza
authors.identifier: 0000-0002-6282-9004
authors.initials: A
authors.lastname: Khataee
authors.affiliation: Department of Engineering, Aarhus University, Hangoevej 2, 8200, Aarhus, Denmark. bentien@eng.au.dk.
authors.forename: Anders
authors.identifier: 0000-0002-7204-9167
authors.initials: A
authors.lastname: Bentien
authors.affiliation: LEPABE-Department of Engineering, University of Porto, Rua Dr. Roberto Frias S/N, P-4200-465, Porto, Portugal. mendes@fe.up.pt.
authors.forename: Adélio
authors.identifier: 0000-0003-2472-3265
authors.initials: A
authors.lastname: Mendes
keywords: anthraquinone; electrochemistry; energy conversion; photoelectrodes; redox flow batteries