Dye-sensitized solar cells with efficiency enhancement surpassing 65% through layer-by-layer assembled plasmonic photoanodes

• Published in: Journal of power sources Vol. 558; p. 232593
• Main Authors: Bhojanaa, Karuppanapillai Baskardurai, Mohammed, Jailani Javith, Manishvarun, Manivannan, Pandikumar, Alagarsamy
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 28.02.2023
• Subjects: Dye-sensitized solar cells; Fermi-level shift; Layer-by-layer assembly; Plasmonic effect; Silver nanoparticles; Plasmonic effect; Dye-sensitized solar cells; Fermi-level shift; Layer-by-layer assembly; Silver nanoparticles
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2022.232593

Even though plasmonic photoelectrodes have paved the way for high-efficiency DSSC, metal nanoparticle degradation in iodine-based electrolytes restricts commercialization. In order to protect the plasmonic nanoparticles, the plasmonic photoelectrode having a layer-by-layer assembly of TiO2/Ag/TiO2 has been developed by a simple photoreduction at various time intervals followed by mild TiCl4 treatment over the TiO2 film and fabricated into dye-sensitized solar cells (DSSC). On evaluating the performance of fabricated DSSC under AM 1.5 G irradiation with the intensity of 100 mWcm−2, the champion cell (η = 11%) shows 65% enhancement in power conversion efficiency compared to the pristine TiO2 photoanode-based DSSC (η = 6.67%). The photocurrent density has been improved due to the surface plasmon resonance effect of Ag nanoparticles and the formation of TiO2 by TiCl4 treatment not only protects the Ag metal nanoparticles as well as creates more dye-loading sites. A negative shift in the Fermi-level caused by the accumulation of electrons in Ag, triggers the open-circuit voltage to increase by 100 mV which is evident from the Mott-Schottky analysis. The electron lifetime value is increased due to increased charge collection efficiency. The champion cell shows 91.5% retainment in efficiency even after 5 days. [Display omitted] •A layer-by-layer assembly of TiO2/Ag/TiO2 photoanode is developed over FTO.•TiO2 layer prevents the Ag from corrosion with electrolyte.•The upward shift of Fermi level offered by Ag leads to increase in VOC.•11% efficiency is achieved due to plasmonic and photo-charging effect.•65% enhanced efficiency and stable for 5 days.