Eliminating J-V hysteresis in perovskite solar cells via defect controlling

Wang

Advanced Energy Materials

et al. 2019

259

196

Organic-inorganic hybrid perovskite solar cells (PSCs) have become a promising candidate in the photovoltaic field due to their high power conversion efficiency and low material cost. However, the development of PSCs is limited by their poor stability under practical conditions in the presence of oxygen, moisture, sunlight, and heat and the current-voltage (I-V) hysteresis. In particular, the hysteretic I-V issue casts doubt on the validity of the photovoltaic performance results that are achieved, making it difficult to evaluate the authentic performance of PSCs. In this review article, the authors focus on understanding the I-V hysteresis behaviour in PSCs and on exploring the possible reasons leading to this hysteresis phenomenon. The various strategies attempted to suppress the I-V hysteresis in PSCs are summarized, and a brief future recommendation is provided.

Section: Improving the Morphology Of The Perovskite Layer By Different Fabrication Methodsmentioning

confidence: 99%

Fundamental Understanding of Photocurrent Hysteresis in Perovskite Solar Cells

Wang

Advanced Energy Materials

et al. 2019

259

196

“…However, interface barriers usually exist between the metal cathode (such as Ag, Al) and the electron transport layer (such as PCBM) in planar p-i-n PVSCs, leading to poor electron extraction [30,31]. Interface engineering should come to the rescue to eliminate any possible interfacial structural and electronic mismatches, to lower interfacial energy barriers, and thus to reduce interfacial trap density [32][33][34][35]. In addition to the aforementioned possible efficiency gain, interface engineering is also expected to improve the chemical stability of the perovskite absorber [36,37], thereby enhancing the overall device stability.…”

Section: Introductionmentioning

confidence: 99%

Molecular design enabled reduction of interface trap density affords highly efficient and stable perovskite solar cells with over 83% fill factor

et al. 2018

ACS Appl. Mater. Interfaces

“…50,51 In addition, the TPC decay time for the CEA-based PePV was shorter than the pristine devices; as shown in Figure 4d, devices with CEA and without CEA showed 0.45 and 1.35 μs TPC decay time, respectively, thus confirming that a more effective charge transport is possible in the CEA-based PePV. 18,44 More notably, these comprehensive observations shown in Figure 4 support that the CEA-induced, better device performances could be caused by the improved charge transport behavior and suppressed trap-assisted recombination to be achieved with the CEAinduced perovskite-film changes.…”

Section: ■ Experimental Sectionmentioning

confidence: 56%

Enhanced Device Performances of MAFACsPb(I_xBr_1–x) Perovskite Solar Cells with Dual-Functional 2-Chloroethyl Acrylate Additives

Cho

Kwon

Choi

et al. 2020

Perovskite photovoltaics (PePVs) tend to suffer from a high density of defects that restrict the device in terms of performances and stability. Therefore, defect passivation and film-quality improvement of perovskite active layers are crucial for highperformance PePVs. In this work, 2-chloroethyl acrylate (CEA) with CO and −Cl groups in Cs 0.175 FA 0.750 MA 0.075 Pb (I 0.880 Br 0.120 ) precursor solutions is introduced as a novel bifunctional additive to act as both a defect passivator and perovskite-growth controller. With the aid of CEA, the perovskite crystallinity and average grain size are improved, and perovskite defects are effectively reduced, thus increasing the representative efficiency (PCE = 19.32%). PePVs with CEA also maintain their initial efficiency of 85% even after about 500 h under air conditions with a humidity of 40 ± 5%. As a result, this study proves that the novel additive CEA can produce higher PePV efficiency and more stable devices.