Interfacial Modification of Mesoporous TiO2 Films with PbI2-Ethanolamine-Dimethyl Sulfoxide Solution for CsPbIBr2 Perovskite Solar Cells

Abstract

As one of the most frequently-used electron-transporting materials, the mesoporous titanium dioxide (m-TiO2) film used in mesoporous structured perovskite solar cells (PSCs) can be employed for the scaffold of the perovskite film and as a pathway for electron transport, and the contact area between the perovskite and m-TiO2 directly determines the comprehensive performance of the PSCs. Because of the substandard interface combining quality between the all-inorganic perovskite CsPbIBr2 and m-TiO2, the development of the mesoporous structured CsPbIBr2 PSCs synthesized by the one-step method is severely limited. Here, we used a solution containing PbI2, monoethanolamine (EA) and dimethyl sulfoxide (DMSO) (PED) as the interfacial modifier to enhance the contact area and modify the m-TiO2/CsPbIBr2 contact characteristics. Comparatively, the performance of the solar device based on the PED-modified m-TiO2 layer has improved considerably, and its power conversion efficiency is up to 6.39%.

Low‐temperature crystallization and growth of CsPbIBr 2 films through PbX 2 ‐DMSO adduct towards stable and efficient carbon‐based all‐inorganic perovskite solar cells

“…The light absorption wavelength range (300‐600 nm) and absorption edge (~600 nm) for EQE is consistent with the UV‐visible absorption spectral study. The integrated current densities from the EQE spectra are basically consistent with the J sc provided in Table 2, wherein the discrepancies may have resulted from the spectral mismatch 12,19 …”

“…The integrated current densities from the EQE spectra are basically consistent with the J sc provided in Table 2, wherein the discrepancies may have resulted from the spectral mismatch. 12,19 The Electrochemical Impedance spectra (EIS) was chronicled to study the influence of DMSO-adducts on the recombination property of the cell (C-IPSC). EIS was performed at an applied bias voltage of 1.0 V under dark conditions and the Nyquist plot was derived from the spectra and is shown in 9A).…”

“…11,[16][17][18] These perovskites are often processed at high temperatures, typically above 250 C, to stabilise the alpha phase, which prevents them from being used in flexible devices. 19,20 Furthermore, mostly expensive noble electrodes (Ag, Au, etc.) and hole selective layers (HSLs) are used in high-efficiency PSCs, but they make the device as unstable one like organic HSLs (spiro-OMeTAD, PEDOT: PSS, etc.).…”

“…Thus, lowering open‐circuit voltage ( V oc ), fill factor (FF), conversion efficiency and ambient stability of the device 11,16‐18 . These perovskites are often processed at high temperatures, typically above 250°C, to stabilise the alpha phase, which prevents them from being used in flexible devices 19,20 . Furthermore, mostly expensive noble electrodes (Ag, Au, etc.)…”

Special Issue: Perovskite Nanostructures: From Material Design to Applications

“…These findings open new pathways for the development of low-cost and quick-processing perovskite photovoltaics. Another interesting work is published by Meng et al reporting the mesoporous titanium dioxide in perovskite solar cells [ 8 ]. The oxide is employed for the scaffold of the perovskite film and as a pathway for electron transport and the contact area between the perovskite and the titanium dioxide.…”