DMSO-Free Tin Halide Perovskites for Indoor Photovoltaics

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Indoor photovoltaic (IPV) technology is crucial for powering batteryless Internet of Things (IoT) devices.
• Tin perovskite solar cells show promise for IPV but suffer from Sn²⁺ oxidation, especially when using dimethyl sulfoxide (DMSO).

Purpose of the Study:

• To explore the IPV performance of DMSO-free tin perovskites (FASnI_3-xBr_x) by adjusting halide composition.
• To enhance the stability and efficiency of tin perovskites for sustainable IoT applications.

Main Methods:

• Fabrication of tin perovskite solar cells using a DMSO-free processing route.
• Tuning halide composition (Br content) in FASnI_3-xBr_x perovskites.
• Characterization using X-ray photoelectron spectroscopy (XPS) and indoor photovoltaic performance testing under 1000 lx illumination.

Main Results:

• Elimination of DMSO prevented Sn⁴⁺ formation, confirmed by XPS.
• Power conversion efficiency (PCE) increased with Br content, reaching 11.1% for FASnI₂Br.
• The DMSO-free device maintained an indoor PCE of 11.9% after six months of storage, demonstrating excellent intrinsic stability.

Conclusions:

• DMSO-free processing is critical for stable and efficient tin perovskite IPV devices.
• Optimized halide composition in tin perovskites offers a viable path for high-performance, lead-free solar cells for IoT.
• This work advances sustainable energy solutions for batteryless electronic devices.