Metal Oxide vs Organic Semiconductor Charge Extraction Layers for Halide Perovskite Indoor Photovoltaics

Area of Science:

• Materials Science
• Renewable Energy
• Semiconductor Physics

Background:

• Halide perovskite solar cells are promising for powering Internet of Things (IoT) devices.
• The selection of hole extraction layers (HELs) significantly impacts indoor perovskite photovoltaics (PVs) performance.
• Understanding HELs' role in indoor light harvesting is critical for material selection and fabrication.

Purpose of the Study:

• To provide insights into the selection of HELs for halide perovskite indoor PVs.
• To investigate the impact of different HELs on indoor light harvesting.
• To address the knowledge gap hindering material selection and industrial-scale fabrication.

Main Methods:

• Systematic investigation of charge carrier dynamics.
• Comparative analysis of devices under dark, light-soaked, and interlayer-passivated conditions.
• Decoupling of bulk and interface defects through sequential measurements.

Main Results:

• First-time unraveling of the detrimental light-soaking effect of metal oxide transport layer-based PVs under indoor lighting.
• Demonstration that this effect is less stringent under 1 sun illumination.
• Revelation of gradual defect passivation from shallow to deep level traps.

Conclusions:

• Metal oxide HELs require interface passivation/engineering for reliable performance in indoor perovskite PVs.
• A design strategy is proposed to mitigate the adverse effects of metal oxide HELs.
• This work facilitates the use of metal oxide HELs in halide perovskite indoor PVs.