High Open Circuit Voltage in Sb2S3/Metal Oxide-Based Solar Cells

This paper presents for the first time Sb 2 S 3 -based solar cells operating on scaffold film. The scaffolds studied are Al 2 O 3 and ZrO 2, for which no electron injection from the Sb 2 S 3 to the Al 2 O 3 or ZrO 2 is possible. As a result, one of the highest open circuit voltages ( V oc ) of 0.712 V was observed for this solar cell configuration. Electron dispersive spectroscopy (EDS) was performed, revealing complete pore filling of the Sb 2 S 3 into the metal oxide pores (e.g., Al 2 O 3 or ZrO 2 ); the complete pore filling of the Sb 2 S 3 is responsible for the photovoltaic performance (PV) of this unique solar cell structure. In addition, intensity modulated photovoltage and photocurrent spectroscopy (IMVS and IMPS) were performed to extract the electron diffusion length. Electron diffusion length in the range of 900 nm to 290 nm (depending on the light intensity) was observed, which further supports the operation of metal oxide/Sb 2 S 3 solar cell configuration. Moreover, the Al 2 O 3 -based cells have longer electron diffusion length than the TiO 2 -based cells, supporting the higher open circuit voltage of the noninjected metal oxide-based cells. This work demonstrates the potential of Sb 2 S 3 to gain high voltage and to perform on a scaffold substrate without requiring electron injection.