Inkjet-Printed SiO_xN_y Barrier Film for Encapsulation of Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy Engineering

Background:

• Perovskite solar cells (PSCs) require robust encapsulation to protect against environmental degradation from oxygen and moisture.
• Thin-film encapsulation is a key strategy for improving the operational stability and longevity of PSCs.

Purpose of the Study:

• To investigate inkjet printing of silicon oxynitride (SiO_xN_y) films as a novel encapsulation method for PSCs.
• To evaluate the barrier properties and environmental stability of SiO_xN_y films fabricated by inkjet printing and vacuum ultraviolet (VUV) treatment.

Main Methods:

• Fabrication of SiO_xN_y barrier films using inkjet printing of perhydropolysilazane (PHPS) solution.
• Conversion of PHPS to SiO_xN_y via vacuum ultraviolet (VUV) treatment.
• Characterization of film transformation using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy.
• Assessment of barrier properties through water immersion tests on encapsulated perovskite films.

Main Results:

• Layer-by-layer inkjet printing resulted in uniform SiO_xN_y films due to surface energy tuning and precursor self-leveling.
• The SiO_xN_y encapsulation demonstrated excellent conformal coating and compatibility with low-temperature processing (< 80°C).
• Encapsulated PSCs retained 93% ± 5% of their initial power conversion efficiency after 1000 hours of storage under ambient conditions (25°C/60%RH).
• The encapsulated PSCs showed remarkable stability, retaining 80% ± 13% efficiency after 1 hour of water immersion.

Conclusions:

• Inkjet printing of SiO_xN_y is a viable and scalable encapsulation strategy for perovskite photovoltaics.
• The method offers precise pattern control (59.4 ± 5.0 µm line width) and room-temperature processing compatibility.
• This approach significantly enhances the environmental stability and durability of PSCs, paving the way for commercial applications.