Large improvement of photovoltaic performance of flexible perovskite solar cells using a multifunctional phospho-ethanolamine-modified SnO2 layer

Abstract

The non-radiative recombination loss caused by diverse defects within SnO 2 electron transport layer (ETL), perovskite film, and their interface greatly hinders the further improvement of the performance and stability of flexible perovskite solar cells (PSCs). Therefore, it is urgent to develop an effective strategy to address these issues. Herein, a multifunctional material, phospho-ethanolamine (PE), is introduced into SnO 2 aqueous colloids to suppress defects and prepare high-quality ETL. The results demonstrate that the incorporation of PE can significantly reduce the number of Sn dangling bonds due to the formation of new Sn-O-P bonds, which is beneficial to ameliorating the electrical properties of SnO 2 and obtaining dense SnO 2 film. Meanwhile, the amino group (NH 2 ) of PE can interact with uncoordinated Pb 2+ in perovskite, thereby suppressing SnO 2 /perovskite interface defects and obtaining improved perovskite film quality. Consequently, the optimized flexible and rigid PSCs based on the SnO 2 -PE composite ETL yield outstanding photoelectric conversion efficiency (PCE) of 18.48% and 21.61%, respectively. Moreover, flexible PSCs based on SnO 2 -PE present excellent mechanical durability, and 90.6% of the original PCE is retained after 1000 bending cycles.

Ecofriendly Mn3O4 as a Novel Hole Transport Material for Efficient and Ultrastable Flexible and Rigid Perovskite Solar Cells

“…The values of conductivity and electron mobility are a criterion to judge whether the Mn 3 O 4 material is a suitable HTM. As illustrated in Figure e, the conductivity calculation of Mn 3 O 4 is determined by measuring the current–voltage ( J – V ) curve of the device structure with FTO/Mn 3 O 4 /Au . The conductivity of the Mn 3 O 4 film is determined using the equation σ = Id /( VA ), where d and A represent the thickness and effective area of the film, respectively.…”

“…As illustrated in Figure 2e, the conductivity calculation of Mn 3 O 4 is determined by measuring the current− voltage (J−V) curve of the device structure with FTO/ Mn 3 O 4 /Au. 42 The conductivity of the Mn 3 O 4 film is determined using the equation σ = Id/(VA), where d and A represent the thickness and effective area of the film, respectively. Similarly, the hole mobility value of Mn 3 O 4 is determined by recording the J−V curve of the device framework with FTO/Spiro-OMeTAD/Mn 3 O 4 /Au under different bias voltages (Figure 2f).…”

Significant Efficiency and Stability Enhancement of Flexible Perovskite Solar Cells Combining with Multifunctional Effects of a Natural Spice

“…[36] It is worth noting that the PbI 2 diffraction peak in the ATB-modified perovskite film appears weaker compared to the pristine, suggesting that ATB may regulate the formation of PbI 2 to enhance the growth state of the perovskite crystal. [37] The absorption spectra of the perovskite films without or with ATB modification are shown in Figure 2b. Obviously, the ATB-modified perovskite film presents a significantly higher light absorption intensity, which can be attributed to the formation of high-quality perovskite film.…”

Substrate Modifications for Stability Improvements of Flexible Perovskite Solar Cells

“…Flexible perovskite solar cells (fPSCs) [ 1–48 ] are of significant interest due to their high power‐per‐weight ratios, potential for low cost fabrication on inexpensive flexible substrates, such as roll‐to‐roll (R2R) manufacturing, and the rising demand for niche applications of solar power (vehicle integrated photovoltaics, space applications, Internet of Things (IoT), wearable electronics, etc.). [ 1–3,5,6,9 ] A significant obstacle toward commercialization fPSCs, among others, is their lower efficiency and stability compared to rigid devices.…”

“…Stability considerations of fPSCs typically take into account mechanical stability and environmental stability. [ 2 ] Consequently, mechanical stability investigations of fPSCs [ 2,14,15,17–22,24–28,32–34,36,37,44–48 ] and environmental stability in ambient without illumination have been very common. [ 2,14–21,24,26,28,32,33,36–39,44,46–48 ] Impressive improvements have been achieved in mechanical stability, with reports of devices being able to withstand 10 000 bending cycles at a radius 0.5 mm.…”