Counter electrode materials for organic-inorganic perovskite solar cells

Abstract

Perovskite solar cells (PSCs) are arising as strong candidates for the next generation of thin-film photovoltaic techniques due to their high efficiency, low-cost, and simple manufacture process. A PSC usually is consisted of several components including in conductive bottom substrate, electron or hole transport layer, perovskite layer, and a counter electrode. However, PSCs are facing issues such as inaccurate evaluation of power conversion efficiency due to hysteresis, poor long-term stability, an inability for continuous manufacturing large area cells, and the use of noble metal as counter electrodes. In fact, a counter electrode is one of the key factors that govern the charge collection, long-term stability, and total cost of PSCs. Despite its importance, less attention has been paid to the exploration of counter electrode materials for PSCs. Here, we provided a summary of the recent development of counter electrode for PSCs, including metal thin-film electrode, super-thin metal thin-film electrode, nanostructured metal electrode, graphene electrode, carbon nanotube electrode, carbon black/graphite electrode, conductive oxide electrode, and polymer electrode. We highlighted findings of novel counter electrode materials towards low cost and stable PSCs as well as some drawbacks with an aim to provide readers a concise overview of the field for developing new counter electrode materials.