2D‐Layered MoS2‐Incorporated TiO2‐Nanofiber‐ Based Dye‐Sensitized Solar Cells

Abstract

AbstractAtomically thin layers of molybdenum disulfide (MoS2) were examined to facilitate electron transport in titanium dioxide (TiO2) nanofiber network for dye sensitized solar cell (DSSC) applications. Raman active modes observed at 382 cm−1 and 406 cm−1 confirmed the presence of atomically thin MoS2 in TiO2 and transmission electron microscopic studies showed MoS2 with a lattice spacing of 3.12 Å. DSSCs using MoS2 incorporated TiO2 nanofiber as a photo‐anode resulted in 27% enhancement in photo‐conversion efficiency (η) than that of the DSSC using only TiO2 as an electron acceptor. A 26% enhancement in the short circuit current density (JSC) achieved by incorporating 0.1 weight % of MoS2 nanoflakes in the bulk of TiO2 confirmed efficient electron transport achieved by suppressing the probability of electron‐hole capture by TiO2 surface states due to the additional electron transport pathways established by MoS2 which facilitated the photo‐generated electrons to reach the transparent electrode by skipping the TiO2 surface states. Results suggest that further increase in the quantity of MoS2 in TiO2 impedes the electron transport in the bulk as observed with 7% and 38% reduction in η for 0.2 and 0.3 weight % of MoS2 in TiO2. This suggests that the DSSC performance can be increased for an optimum concentration of MoS2 in TiO2 by establishing efficient transport pathways towards the transparent electrode.