Fig 1

Perovskite solar cells under shadow shading: (a) Circuit diagram of sub-cells in a series-connected cell after being shaded; (b) Hot spot phenomenon of perovskite solar cells under reverse bias [23]. (b) Adapt with permission from Ref. [23], Copyright 2020 Royal Society of Chemistry."

Fig 2

The optoelectronic performance of perovskite solar cells under reverse bias: (a) J−V curves of metal electrode perovskite solar cells as the reverse bias gradually increases [23]; (b) J−V curves of metal-free electrode perovskite solar cells as the reverse bias gradually increases [23]; (c) The J−V curve of device under applying a bias of −0.8 V for 60 s and recover when left in the dark [39]; (d) The J−V curve of device under applying a bias of −1.5 V for 60 s and recover when left in the dark [39]; (e) J−V curves of perovskite solar cells with different structures in the dark state [40]; (f) Performance changes of perovskite solar cells in tests with different fixed bias increment time [43]. (a, b) Adapt with permission from Ref. [23], Copyright 2020 Royal Society of Chemistry; (c, d) Adapt with permission from Ref. [39], Copyright 2024 Springer Nature; (e) Adapt with permission from Ref. [40], Copyright 2017 John Wiley and Sons; (f) Adapt with permission from Ref. [43], Copyright 2021 John Wiley and Sons."

Fig 3

Summary of stability data of perovskite solar cells under reverse bias: (a) A summary of the breakdown voltage of perovskite solar cells with different PCEs; (b) A summary of ageing duration of perovskite solar cells under different fixed reverse biases."

Table 1

PCE of perovskite solar cells and corresponding breakdown voltage."

Table 2

Ageing duration of perovskite solar cells under fixed reverse bias."

Fig 4

Summary of self-recovery mechanisms of perovskite solar cells: (a) Schematic diagram of MAPbI3 single-crystal perovskite solar cells under reverse bias [36]; (b) DLCP testing curve of perovskite solar cells after reverse bias [36]; (c) Energy diagram of mobile defects (Ii' and VI•) in perovskite [38]; (d) The ageing and recovery behavior of perovskite devices [48]; (e) s-EQE spectra and Gaussian fitting of metal electrode perovskite solar cells after 10 h of light soaking and after being left overnight [49]. (a, b) Adapt with permission from Ref. [36], Copyright 2021 Springer Nature; (c) Adapt with permission from Ref. [38], Copyright 2024 Springer Nature; (d) Adapt with permission from Ref. [48], Copyright 2021 Elsevier; (e) Adapt with permission from Ref. [49], Copyright 2020 John Wiley and Sons."

Fig 5

Summary of irreversible loss mechanisms of perovskite solar cells: (a) The migration and oxidation of iodide ions and the migration and reduction of metal ions, and the formation of conductive paths [24]; (b) The paired electrochemical reactions between perovskite solar cells and silver (or gold) electrodes under reverse bias [39]; (c) Williamson-Hall analysis of perovskite films induced by light and bias [50]; (d) Infrared thermography of perovskite solar cells at −5 V [40]. (a) Adapt with permission from Ref.24, Copyright 2024 Springer Nature; (b) Adapt with permission from Ref.39, Copyright 2024 Springer Nature; (c) Adapt with permission from Ref.50, Copyright 2019 Springer Nature; (d) Adapt with permission from Ref.40, Copyright 2018 John Wiley and Sons."

Fig 6

Application of blocking layers in perovskite solar cells to enhance reverse bias stability: (a) Schematic diagram of the composite electrode [30]; (b) The reverse bias stability of perovskite solar cells with and without composite electrodes [30]; (c) The scheme of barrier reinforcement through modified device architecture [24]; (d) The PCE changes of different perovskite solar cells under −1.6 V ageing [24]; (e) The optoelectronic performance of fresh and aged devices [51]; (f) Normalized PCE devices with and without MoO3 interfacial layer under different ageing conditions [52]. (a, b) Adapt with permission from Ref. [30], Copyright 2022 Springer Singapore; (c, d) Adapt with permission from Ref. [24], Copyright 2024 Springer Nature; (e) Adapt with permission from Ref. [51], Copyright 2016 John Wiley and Sons; (f) Adapt with permission from Ref. [52], Copyright 2019 Elsevier."

Fig 7

Enhancing reverse bias stability of perovskite solar cells through chemical passivation: (a) Device structure of single-crystal perovskite solar cells with MDMS modification [37]; (b) J−V curves of single-crystal solar cells with and without MDMS modification on MAPbI3 under −1 V reverse bias for different durations [37]; (c and d) Schematic illustration of 2D perovskite passivation on different n layers of 3D perovskite and J−V characteristics of untreated and passivated devices in the dark [53]; (e) Schematic illustration of C60 with non-directional iodine affinity and PFI with directional iodine affinity [38]; (f) Normalized PCE changes of perovskite solar cells with PFI modification under various reverse bias conditions [38]. (a, b) Adapt with permission from Ref. [37], Copyright 2023 John Wiley and Sons; (c, d) Adapt with permission from Ref. [53], Copyright 2023 John Wiley and Sons; (e, f) Adapt with permission from Ref. [38], Copyright 2024 Springer Nature."

Fig 8

Enhanced reverse bias stability of perovskite solar cells through HTL and metal layers replacement or modification: (a) Perovskite solar cells architectures with different TiO2 layers, (b) and the comparison their J−V curves before and after ageing under −2.5 V reverse bias [54]; (c) Optical microscope images of surface changes in device structures with different TiO2 layer under different ageing conditions [54]; (d) Schematics of the role of PTAA and Au electrode on inhibiting the reduction and oxidation reaction [39]; (e) The breakdown voltage variation of perovskite solar cells with Ag electrode/Au electrode and different HTLs [39]; (f) Schematics demonstrating that the silicon subcell bears a large part of the reverse bias in perovskite/silicon tandems [55]; (g) J−V curves of perovskite solar cells, silicon solar cells, and perovskite/silicon tandem solar cells under reverse bias in the dark [55]; (h) J−V curves of encapsulated perovskite solar cells, silicon solar cells, and perovskite/silicon tandem solar cells after being subjected to −2 V reverse bias for 12 h [55]. (a, b, c) Adapt with permission from Ref. [54], Copyright 2022 American Chemical Society; (d, e) Adapt with permission from Ref. [39], Copyright 2024 Springer Nature; (f, g, h) Adapt with permission from Ref. [55], Copyright 2023 Elsevier."

Fig 9

Test methods for reverse bias stability of perovskite solar cells: (a) J−V curves of perovskite solar cells scanned from positive to negative voltage in the dark state [39]; (b) J−V curves of perovskite solar cells after being subjected to increasing reverse biases for 60 s [39]; (c) PCE changes of perovskite solar cells with PFI/PCBM treatment after being maintained at 85 ℃ and −4.5 V reverse bias for a certain period of time [38]; (d) Schematics of a module scheme and equivalent circuit of a sub-cell under shadow shading [24]; (e) PCE evolution of modules with one sub-cell under shadow shading [24]. (a, b) Adapt with permission from Ref. [39], Copyright 2024 Springer Nature; (c) Adapt with permission from Ref. [38], Copyright 2024 Springer Nature; (d, e) Adapt with permission from Ref. [24], Copyright 2024 Springer Nature."

Fig 10

Material analysis of perovskite film and solar cells under reverse bias ageing: (a) Comparison of TOF-SIMS results between treated and untreated samples aged at −3.5 V for 6 min [24]; (b) XPS spectra of Ag in the device before and after ageing [39]; (c) XPS spectra of Cu at the buried interface of the perovskite film after ageing [24]; (d) The ratio of surface element content (calculated by XPS) after the metal layer is peeled off [38]; (e) XRD patterns of the device before and after ageing [24]; (f) STEM-EDX images and elemental mapping of unencapsulated perovskite solar cells after reverse bias ageing [55]; (g) 1H-NMR spectra of the device before and after ageing [24]; (h) PL mapping images of the device before and after ageing [24]; (i) PL spectra of sample regions with different degradation degrees [24]. (a, c, e, g, h, i) Adapt with permission from Ref. [24], Copyright 2024 Springer Nature; (b) Adapt with permission from Ref. [39], Copyright 2024 Springer Nature; (d) Adapt with permission from Ref. [38], Copyright 2024 Springer Nature; (f) Adapt with permission from Ref. [55], Copyright 2023 Elsevier."