Enhancing dye-sensitized solar cell efficiency through broadband near-infrared upconverting nanoparticles

Abstract

The inability to utilize near infrared (NIR) light has posed a stringent limitation for the efficiencies of most single-junction photovoltaic cells such as dye-sensitized solar cells (DSSCs). Here, we describe a strategy to alleviate the NIR light harvesting problem by upconverting non-responsive NIR light in a broad spectral range (over 190 nm, 670-860 nm) to narrow solar-cell-responsive visible emissions through incorporated dye-sensitized upconversion nanoparticles (DSUCNPs). Unlike typically reported UCNPs with narrow and low NIR absorption, the organic dyes (IR783) anchored on the DSUCNP surface were able to harvest NIR photons broadly and efficiently, and then transfer the harvested energy to the inorganic UCNPs (typically reported), entailing an efficient visible upconversion. We show that the incorporation of DSUCNPs into the TiO photoanode of a DSSC is able to elevate its efficiency from 7.573% to 8.568%, enhancing the power conversion efficiency by about 13.1%. We quantified that among the relative efficiency increase, 7.1% arose from the contribution of broad-band upconversion in DSUCNPs (about ∼3.4 times higher than the highest previously reported value of ∼2.1%), and 6.0% mainly from the scattering effect of DSUCNPs. Our strategy has immediate implications for the use of DSUCNPs to improve the performance of other types of photovoltaic devices.

Rational design of near‐infrared absorbing organic dyes: Controlling the HOMO–LUMO gap using quantitative molecular orbital theory

“…Near‐infrared (NIR) absorbing organic dyes (650–950 nm) are highly sought after for application as an emitter in tissue imaging and organic electronics, and as a photosensitizer in organic photovoltaics . Their tunability, synthetical accessibility, and low toxicity give them an advantage over alternate inorganic materials . However, advancing such organic dyes is hampered by complex molecular arrangements and a large π‐scaffold with poor excited state intramolecular charge transfer (ICT) nature .…”

Energy Transfer in Dye‐Coupled Lanthanide‐Doped Nanoparticles: From Design to Application

“…e) Currentdensity-voltage (J-V)c urveso fd ye-sensitizeds olar cell(DSSC), dye-sensitized solar cell-upconversion NPs (DSSC-UCNPs), and dye-sensitized solar cell-dye-sensitized upconversion NPs (DSSC-DSUCNPs) under l = 800 nm NIR laser irradiation.Parts d) and e) are adaptedw ith permission from Ref. [46],c opyright 2017 Royal SocietyofC hemistry.…”

“…reported the use of multidye‐sensitized upconversion NPs for information storage . Finally, Chen and co‐workers also validated the possibility of using dye‐sensitized broadband upconversion NPs for enhancing the conversion efficiency of dye‐sensitized solar cells (Figure d and e) …”

Commercial Upconversion Phosphors with High Light Harvesting: A Superior Candidate for High‐Performance Dye‐Sensitized Solar Cells

“…This fact encourages researchers to explore new strategies for enhancing the LHE of photoanodes. One promising approach is to introduce upconversion materials into photoanodes, thus converting NIR light to visible light …”