Concepedia

Efficient and stable solution-processed planar perovskite solar cells via contact passivation

Hairen Tan, Ankit Jain, Oleksandr Voznyy, Xinzheng Lan, F. Pelayo Garcı́a de Arquer, James Z. Fan, Rafael Quintero‐Bermudez, Mingjian Yuan, Yicheng Zhao, Fengjia Fan,

Science · 2017 · 2.3K citations · 53 references

DOI Full text

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TL;DR

Planar perovskite solar cells fabricated entirely by low‑temperature solution processing (<150 °C) promise simple manufacturing, flexible substrates, and tandem integration, but require an electron‑selective layer compatible with such processing. The authors aim to introduce a contact‑passivation strategy using chlorine‑capped TiO₂ colloidal nanocrystals to reduce interfacial recombination and strengthen interface binding in low‑temperature planar cells. They implement this by depositing a chlorine‑capped TiO₂ colloidal nanocrystal film as the electron‑selective layer during low‑temperature solution processing. The resulting devices achieve certified efficiencies of 20.1 % and 19.5 % for 0.049 cm² and 1.1 cm² active areas, and retain 90 % (97 % after dark recovery) of their initial performance after 500 h of continuous room‑temperature operation at maximum power point under 1‑sun illumination.

Abstract

Planar perovskite solar cells (PSCs) made entirely via solution processing at low temperatures (<150°C) offer promise for simple manufacturing, compatibility with flexible substrates, and perovskite-based tandem devices. However, these PSCs require an electron-selective layer that performs well with similar processing. We report a contact-passivation strategy using chlorine-capped TiO2 colloidal nanocrystal film that mitigates interfacial recombination and improves interface binding in low-temperature planar solar cells. We fabricated solar cells with certified efficiencies of 20.1 and 19.5% for active areas of 0.049 and 1.1 square centimeters, respectively, achieved via low-temperature solution processing. Solar cells with efficiency greater than 20% retained 90% (97% after dark recovery) of their initial performance after 500 hours of continuous room-temperature operation at their maximum power point under 1-sun illumination (where 1 sun is defined as the standard illumination at AM1.5, or 1 kilowatt/square meter).