Details

Autor(en) / Beteiligte

• Khataee, Amirreza
• Azevedo, João
• Dias, Paula
• Ivanou, Dzmitry
• Dražević, Emil
• Bentien, Anders
• Mendes, Adélio

Titel

Integrated design of hematite and dye-sensitized solar cell for unbiased solar charging of an organic-inorganic redox flow battery

Ist Teil von

• Nano energy, 2019-08, Vol.62, p.832-843

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Integration of the photoelectrochemical cells and redox flow batteries (RFBs) is conceptualized as solar redox flow cells (SRFCs). The SRFC opens an opportunity for simultaneous electrochemical conversion and storage of solar energy in a single device. This work proposes a SRFC which integrates stable hematite (α-Fe2O3) photoanode with a near-neutral organic-inorganic RFB using organic and low-cost redox pair anthraquinone-2,7-disulfonate disodium (AQDS) on the negative side and iodide/iodine (I−/I2) redox couple on the positive side. The AQDS/iodide RFB exhibited a stable battery cycling with a cell voltage of ~0.8 V, a high coulombic efficiency of 99.2% and a peak power density of 0.22 W⋅cm−2. The hematite yielded a stable performance in contact with iodide/iodine solution with pH 5.5, despite known stability issues for pH < 7. Electrochemical impedance spectroscopy was used to elucidate the main semiconductor/electrolyte charge transfer mechanisms and rates and energy level alignment of hematite with redox pair voltages. Finally, to photocharge the AQDS/iodide SRFC unbiasedly, a tandem system was used which includes hematite photoelectrode connected in series with a dye-sensitized solar cell (DSSC). The tandem photoelectrode provided 1.6 V of photovoltage that is sufficient to fully charge the RFB. [Display omitted] •Unbiased solar charging of quinone-iodide redox flow battery is presented using a tandem system.•Tandem system is made up of hematite in series with a dye-sensitized solar cell, provides 1.6 V photovoltage.•Unlike the stability issues of hematite at pH < 7, it shows stable performance with iodide/iodine solution at pH 5.5.•Quinone-iodide redox flow battery exhibits average current and energy efficiencies of 99.2% and 76%, respectively.