Counter-Doping Effect by Trivalent Cations in Tin-Based Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Tin (Sn)-based perovskite solar cells (PSCs) suffer from low open-circuit voltage due to carrier recombination.
• Oxidation of the perovskite layer leads to high p-type doping, hindering device performance.

Purpose of the Study:

• To investigate the introduction of trivalent cations as a counter-doping strategy for oxidized Sn-based perovskites.
• To improve the performance and stability of Sn-based PSCs by mitigating oxidation effects.

Main Methods:

• Incorporation of trivalent antimony (Sb³⁺) ions into the perovskite crystal lattice.
• Characterization of the effects of Sb³⁺ on carrier recombination, carrier lifetime, and carrier mobility.
• Fabrication and testing of Sn-based PSC devices with Sb³⁺ doping.

Main Results:

• Sb³⁺ effectively counter-doped the oxidized perovskite layer.
• Improved carrier lifetime and carrier mobility were observed in Sb³⁺-doped perovskite layers.
• A relative power conversion efficiency (PCE) enhancement of 31.4% was achieved.
• Enhanced shelf-storage stability was demonstrated for the modified devices.

Conclusions:

• Trivalent cation doping, specifically with Sb³⁺, is a viable strategy to compensate for Sn-based perovskite oxidation.
• This approach offers a novel and potentially universal method to enhance the performance and stability of Sn-based PSCs and other optoelectronic devices.