Work

Performance Enhancement of Lead-Free Tin-Based Perovskite Solar Cells with Reducing Atmosphere-Assisted Dispersible Additive

Year: 2017

Type: article

Abstract: Sn-based halide perovskite materials have attracted tremendous attention and have been employed successfully in solar cells. However, their high conductivities resulting from the unstable divalent Sn state in the structure cause poor device performance and poor reproducibility. Herein, we used excess tin iodide (SnI 2 ) in Sn-based halide perovskite solar cells (ASnI 3, A = Cs, methylammonium, and formamidinium tin iodide as the representative light absorbers) combined with a reducing atmosphere to stabilize the Sn 2+ state. Excess SnI 2 can disperse uniformly into the perovskite films and functions as a compensator as well as a suppressor of Sn 2+ vacancies, thereby effectively reducing the p-type conductivity. This process significantly improved the solar cell performances of all the ASnI 3 materials on mesoporous TiO 2 . Optimized CsSnI 3 devices achieved a maximum power conversion efficiency of 4.81%, which is the highest among all inorganic Pb-free perovskite solar cells to date.

Source: ACS Energy Letters

DOI: 10.1021/acsenergylett.7b00171

Authors: Tze-Bin Song, Takamichi Yokoyama, Shinji Aramaki, Mercouri G. Kanatzidis

Institutions: Northwestern University, Mitsubishi Chemical Group Science and Technology Research Center (Japan)

Language: English

Topic: Perovskite Materials and Applications

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: green