Stability of organometal halide perovskite solar cells and role of HTMs: recent developments and future directions

Abstract

Perovskite solar cells (PSCs) have recently emerged as one of the most exciting fields of research of our time, and the World Economic Forum in 2016 recognized them as one of the top 10 technologies in 2016. With 22.7% power conversion efficiency, PSCs are poised to revolutionize the way power is produced, stored and consumed. However, the widespread use of PSCs requires addressing the stability issue. Therefore, it is now time to focus on the critical step i.e. stability under the operating conditions for the development of a sustainable and durable PV technology based on PSCs. In order to improve the stability of PSCs, hole transport materials (HTMs) have been considered as the paramount components. This is due to the fact that most of the organic HTMs possess a hygroscopic and acidic nature that leads to poor stability of the PSCs. This article reviews briefly but comprehensively the environmental stability issues of PSCs, fundamentals, strategies for improvement, the role of HTMs towards stability and various types of HTMs. Also the environmental parameters affecting the performance of perovskite solar cells including temperature, moisture and light soaking environment have been considered.

The use of nickel oxide as a hole transport material in perovskite solar cell configuration: Achieving a high performance and stable device

“…51,103,104,124,152,153 Several works have been reported with different techniques on ways of improving the stability of perovskite devices. 49,92,146,147,[154][155][156][157][158][159][160][161][162][163][164][165][166][167][168][169] Dopantfree hole transporters have been reported to maintain good stabilities of perovskite devices. 22,170,171 This was achieved because the photovoltaic properties of the device like its fill factor, short-circuit current and open-circuit voltage values are increased by inorganic hole transport materials like NiO.…”

“…Nickel oxide amongst other inorganic hole transporters is a relatively cheap material that is highly resistant to chemical and thermal treatments and also enhances the stability of PSCs 51,103,104,124,152,153 . Several works have been reported with different techniques on ways of improving the stability of perovskite devices 49,92,146,147,154‐169 . Dopant‐free hole transporters have been reported to maintain good stabilities of perovskite devices 22,170,171 .…”

Degradable and Dissolvable Thin-Film Materials for the Applications of New-Generation Environmental-Friendly Electronic Devices

“…Perovskite materials (ABX 3 ) including oxide-perovskite and halide-perovskite are a special kind of inorganic film, whose special characteristic comes from its unique properties. The most remarkable feature is that it can produce a photothermal effect, which means that the conversion of light and electricity in the environment can be realized through these films [107,108] [111].…”

Hole Transport Materials in Conventional Structural (n–i–p) Perovskite Solar Cells: From Past to the Future

“…Representative dopants are bis(trifluoromethane)sulfonamide lithium salt (LiTFSI), cobalt (III) complexes, and 4‐ tert ‐butylpyridine (tBP) . LiTFSI accelerates the oxygen‐induced oxidation of spiro‐OMeTAD as follows …”

“…Representative dopants are bis(trifluoromethane)sulfonamide lithium salt (LiTFSI), cobalt (III) complexes, and 4-tertbutylpyridine (tBP). [22,23] LiTFSI accelerates the oxygen-induced oxidation of spiro-OMeTAD as follows [24]…”