Moisture‐Resilient Perovskite Solar Cells for Enhanced Stability

Abstract

With the rapid rise in device performance of perovskite solar cells (PSCs), overcoming instabilities under outdoor operating conditions has become the most crucial obstacle towards their commercialization. Among stressors such as light, heat, voltage bias, and moisture, the latter is arguably the most critical, as it can decompose metal‐halide perovskite (MHP) photo‐active absorbers instantly through its hygroscopic components (organic cations and metal halides). In addition, most charge transport layers (CTLs) commonly employed in PSCs also degrade in the presence of water. Furthermore, photovoltaic module fabrication encompasses several steps, such as laser processing, sub‐cell interconnection, and encapsulation, during which the device layers are exposed to the ambient atmosphere. Therefore, as a first step towards long‐term stable perovskite photovoltaics, it is vital to engineer device materials towards maximizing moisture resilience, which can be accomplished by passivating the bulk of the MHP film, introducing passivation interlayers at the top contact, exploiting hydrophobic CTLs, and encapsulating finished devices with hydrophobic barrier layers, without jeopardizing device performance. In this article, we review existing strategies for enhancing the performance stability of PSCs and formulate pathways toward moisture‐resilient commercial perovskite devices.This article is protected by copyright. All rights reserved

Accelerating Thermal Transfer in Perovskite Films for High‐Efficiency and Stable Photovoltaics

“…Therefore, many strategies have been developed to prolong the device service lifetime, with the emphasis mainly focused on controlling the crystallization kinetics to improve the film quality, [6,7] healing the defective perovskite lattice, [8,9] and blocking the inflow of harmful elements. [10] As expected, all the above technologies are indeed effective in improving the lattice stability against moisture and light, but still unable to avoid the generation and accumulation of heat even within the encapsulated PSCs because of the photo-to-thermal conversion and low thermal conductivity (𝜅) of perovskite film. [11] As a result, the operational temperature of PSC is elevated under the concurrent effect of incident sunlight and local environment temperature (more serious in concentrated light and high temperature conditions), [12,13] which in return leads to the structural change and lattice expansion of perovskite film and adjacent charge transfer layers as well, [14][15][16] thereby permanently degrading the photovoltaic performance even after cooling down to room temperature.…”

Cross-linking polymerization boosts the performance of perovskite solar cells: from material design to performance regulation

“…Perovskite materials are highly sensitive to moisture, which is the main degradation cause of perovskite under an ambient atmosphere. 150 In the case of polycrystalline perovskite films, the moisture penetrates and diffuses into the perovskite film through GBs. 151,152 Abundant vacancy defects at GBs and the surface of perovskite film can be easily combined with H 2 O molecules, which speeds up the structural decomposition of perovskites.…”

Cross-linking strategies for efficient and highly stable perovskite solar cells

“…40 To date, CLMs utilized as additive/passivation agents, interfacial modifiers, and charge-transporting materials have shown immense potential in realizing efficient PSCs with synchronously enhanced stabilities such as chemical stability, processing stability, thermal stability, as well as mechanical stability. Although several detailed review articles on the stability issues of PSCs have been published previously, 41–45 no reviews have focused on cross-linking strategies to our knowledge. Hence, this review aims to timely and fully summarize the recent progress of cross-linking strategies and provide feasible research directions in the design of cross-linking materials in a bid to enable high-performance and stable PSCs in the near future.…”