Invention:
This technology involves the use of a removable ‘peel and stick electrolyte’ probe for detecting defects in perovskite materials. This is an improvement on previous technology that increases sensitivity of defect detection in device-relevant triple cation perovskites.
Background:
The development of next-generation flexible optoelectronic devices has focused on the incorporation of solution processable lead halide perovskite materials as an active layer because of their high-power conversion efficiency and easy accessibility. In the last decade, the certified power conversion efficiencies (PCEs) of perovskite solar cells have leaped from 3.8% to a maximum of 25.2% reached in 2020. Although various routes such as compositional engineering, interface modification, surface passivation and encapsulation have been attempted to improve device efficiency, the record for flexible perovskite solar cells is advancing rather slowly, especially in modules. As a result, novel techniques are needed to examine recent work more closely to expedite innovation toward higher PCEs by characterizing and controlling defect populations and improve long-term stability by understanding underlying chemical-physical-electronic equilibration mechanisms to enhance scalability and enable broad applicability.
In 2016, a novel “triple cation” reproducible perovskite with more pure and highly monolithic grains was developed that demonstrated consistent PCEs above 20%. Since then, these perovskites have attracted a broad interest based on their increased absorption, improved stability, decrease in interfacial recombination and number of defects. While their efficiency approximates silicon’s lab record, lattice distortions, grain boundaries, impurities in the perovskite’s crystal lattice and most importantly the connection with other layers contribute to phase instabilities, electronic defects and ion migration that are exacerbated under photon flux, heat, humidity, and/or electrical bias. Once ions leave the lattice they propagate through the active layer not only as defects, but also as active chemical species. In the last 5 years, the interest in quantifying this number of defects has grown tremendously, which caused a surge in the number of methodologies to detect or predict them.
Applications:
- Solar cell defect detection
- Trouble-shooting semi-conductor films
Advantages:
- Improved durability
- Improved reliability
