Controlled Interfacial Electron Dynamics in Highly Efficient Zn₂SnO₄‐Based Dye‐Sensitized Solar Cells

Abstract

Among ternary oxides, Zn2 SnO4 (ZSO) is considered for dye-sensitized solar cells (DSSCs) because of its wide bandgap, high optical transmittance, and high electrical conductivity. However, ZSO-based DSSCs have a poor performance record owing largely to the absence of systematic efforts to enhance their performance. Herein, general strategies are proposed to improve the performance of ZSO-based DSSCs involving interfacial engineering/modification of the photoanode. A conformal ZSO thin film (blocking layer) deposited at the fluorine-doped tin oxide-electrolyte interface by pulsed laser deposition suppressed the back-electron transfer effectively while maintaining a high optical transmittance, which resulted in a 22 % improvement in the short-circuit photocurrent density. Surface modification of ZSO nanoparticles (NPs) resulted in an ultrathin ZnO shell layer, a 9 % improvement in the open-circuit voltage, and a 4 % improvement in the fill factor because of the reduced electron recombination at the ZSO NPs-electrolyte interface. The ZSO-based DSSCs exhibited a faster charge injection and electron transport than their TiO2 -based counterparts, and their superior properties were not inhibited by the ZnO shell layer, which indicates their feasibility for highly efficient DSSCs. Each interfacial engineering strategy could be applied to the ZSO-based DSSC independently to lead to an improved conversion efficiency of 6 %, a very high conversion efficiency for a non-TiO2 based DSSC.

High-performance flexible perovskite solar cells exploiting Zn2SnO4 prepared in solution below 100 °C

“…14 ). In addition, it has a wide optical band gap of 3.8 eV and a relatively low refractive index of ∼2.0 in the visible spectrum 15 16 . Furthermore, the conduction band edge position that is similar to that of TiO 2 and ZnO makes it an excellent photoelectrode in emerging solar cell technologies, such as PSC, dye sensitized solar cell (DSSC) and organic photovoltaic (OPV) 17 18 19 .…”

Highly porous Zinc Stannate (Zn2SnO4) nanofibers scaffold photoelectrodes for efficient methyl ammonium halide perovskite solar cells

“…On the other hand, there is no substantial reports are available based on ternary metal oxide (TMO) as electron transporting layer (ETL) for PSC. Shin et al reported nano-particulate BaSnO 3 and Zn 2 SnO 4 ternary metal oxides (TMO) for dye sensitized solar cells, and demonstrated 6.2%, 6%, power conversion efficiency (PCE) respectively1920. Moreover, Zn 2 SnO 4 nanoparticles have been used for PSC and demonstrated ~7% PCE21.…”

Improving the efficiency of dye-sensitized solar cells by photoanode surface modifications

“…The increased photocurrent density may be attributed to the effective charge injection from strongly anchored dyes by the equilibrium-shifting action of TEOS, as well as to a downward CBE shift. Moreover, the device showed a better long-term stability than the [101] untreated reference cell. Post-treatment of nanoporous TiO2 films with a solution of TiCl4 has been a very common method for fabricating a nanoporous TiO2 films that serve both as a substrate for the dye and as the electron conductor.…”