RESUMEN
The metal oxide electron transport layers (ETLs) of n-i-p perovskite solar cells (PSCs) are dominated by TiO2 and SnO2, while the efficacy of the other metal oxide ETLs still lags far behind. Herein, an emerging, economical, and environmentally friendly metal oxide, antimony oxide (Sb2Ox, x = 2.17), prepared by chemical bath deposition is reported as an alternative ETL for PSCs. The deposited Sb2Ox film is amorphous and very thin (â¼10 nm) but conformal on rough fluorine-doped tin oxide substrates, showing matched energy levels, efficient electron extraction, and then reduced nonradiative recombination in PSCs. The champion PSC based on the Sb2Ox ETL delivers an impressive power conversion efficiency of 24.7% under one sun illumination, which represents the state-of-the-art performance of all metal oxide ETL-based PSCs. Additionally, the Sb2Ox-based devices show improved operational and thermal stability compared to their SnO2-based counterparts. Armed with these findings, we believe this work offers an optional ETL for perovskites-based optoelectronic devices.
RESUMEN
Tin oxide (SnO2) as electron transportation layer (ETL) has demonstrated remarkable performance applied in perovskite solar cells but still accommodated a host of defects such as oxygen vacancies, uncoordinated Sn4+ , and absorbed hydroxyl groups. Here, we use inorganic sodium thiosulfate Na2S2O3 to modify SnO2 nanoparticles in a bulk blending manner. Strong interaction between Na2S2O3 and SnO2 occurs, as reflected from the elemental chemical state change. The interaction has endowed the SnO2 film with better uniformity, increased conductivity, and more matched energy level with perovskite. Moreover, the modified SnO2 film as a substrate could promote the crystallization of perovskite by suppressing unreacted residual PbI2. The trap density from perovskite bulk to the SnO2 film across their interface has been effectively reduced, thus inhibiting the nonradiative recombination and promoting the transportation and extraction of charge carriers. Finally, the solar cell based on modified SnO2 has achieved a champion efficiency of 25.2%, demonstrating the effectiveness and potential of sulfur-containing molecules on optimizing the SnO2 property.