Groups-dependent phosphines as the organic redox for point defects elimination in hybrid perovskite solar cells

Postpassivation of Cs0.05(FA0.83MA0.17)0.95Pb(I0.83Br0.17)3 Perovskite Films with Tris(pentafluorophenyl)borane

“…Halide perovskite solar cells (PSCs) have been in the spotlight in the photovoltaic field, profiting from their outstanding optoelectronic properties, low-cost fabrication, and simple processing technique. − In the last decade, the power conversion efficiency (PCE) of PSCs has rapidly enhanced to 25.2 from 3.8%. , Halide perovskite, as a light-absorption layer, is vital for highly efficient PSCs (efficiency >20%). However, inherent crystal defects are generated inside a polycrystalline perovskite film during perovskite film fabrication procedure and device operation process. , Although most defects give rise to shallow electronic states in bandgap edges, PSC devices are still confronted with the small number of deep trap states that are in charge of the nonradiative recombination centers in perovskite layers, damaging the optoelectronic properties of the device. − Simultaneously, many unstable factors (moisture, oxygen, and ultraviolet light) also originate from these defects, which greatly attenuates the stability of the photovoltaic device . Therefore, the key to efficient and stable PSCs is to reduce or passivate those defects.…”

“…Relevant studies reveal that uncoordinated ions, metallic Pb (Pb 0 ) and iodide (I 0 ), are the central deep-level trap states lying in perovskite films. , Also, the report exhibits that Pb 0 is the primary defect that deteriorates device performance and stability . Approaches, including composition engineering, film optimization engineering, additive engineering, ,,, and interfacial modification engineering, have been presented to reduce Pb 0 defects. Zhong et al employed organic phosphine redox pair as a Pb 0 and I 0 defects stabilizer.…”

“…Zhong et al employed organic phosphine redox pair as a Pb 0 and I 0 defects stabilizer. The relevant PSC gained enhanced performance and long-term stability . Zhou et al proved that introducing Eu 3+ -Eu 2+ redox pair into the PSC can effectively eliminate Pb 0 and I 0 defects, which greatly inhibited the degradation of PSC devices .…”

“…However, inherent crystal defects are generated inside a polycrystalline perovskite film during perovskite film fabrication procedure and device operation process. 6,7 Although most defects give rise to shallow electronic states in bandgap edges, PSC devices are still confronted with the small number of deep trap states that are in charge of the nonradiative recombination centers in perovskite layers, damaging the optoelectronic properties of the device. 8−11 Simultaneously, many unstable factors (moisture, oxygen, and ultraviolet light) also originate from these defects, which greatly attenuates the stability of the photovoltaic device.…”

“…The relevant PSC gained enhanced performance and long-term stability. 7 Zhou et al proved that introducing Eu 3+ -Eu 2+ redox pair into the PSC can effectively eliminate Pb 0 and I 0 defects, which greatly inhibited the degradation of PSC devices. 15 Qi et al found that pentaerythritol tetrakis(3-mercaptopropionate) can simultaneously passivate uncoordinated Pb 2+ and block the formation of Pb 0 defects.…”