Efficient and Stable Inverted Perovskite Solar Cells Using Donor–Acceptor–Donor Small Molecules to Tuning NiO_x/Perovskite Interfacial Microstructure

Abstract

Nickel oxide (NiO x ) is one of the most widely used inorganic hole transport materials for inverted perovskite solar cells (PSCs), which has the advantages of low cost, easy preparation, and good stability. However, the energy‐level mismatch and interfacial redox reactions at the NiO x /perovskite interface limit the performance of NiO x ‐based PSCs. Herein, triphenylamine‐2,1,3‐benzothiadiazole‐triphenylamine (TBT) small‐molecule material is first used as an interfacial modification layer between NiO x and perovskite. The deposition of TBT on NiO x helps to hinder the contact between NiO x and perovskite, improves the electrical conductivity, passivates interfacial defects, and inhibits the recombination of interfacial carriers. TBT makes the valance band top energy level of NiO x better match that of perovskite and promotes the hole transfer at NiO x /perovskite interface, and the hole transfer rate increases from 2.19 × 1010 to 4.12 × 1010 s−1. The TBT‐based device obtains a champion power conversion efficiency (PCE) of 21.84%, much higher than the control device (18.62%). Furthermore, the optimized device which is conserved in 30 ± 5% relative humidity and 25 °C environments more than 1000 h retains 90% of the initial efficiency. A effective strategy to improve the PCE and stability of NiO x ‐based PSCs is provided.

A simple passivation strategy of Na-dithienylethene for highly efficient and stable perovskite solar cells

“…To quantitatively describe the differences in charge transfer, we performed tting of the GSB dynamics, and the results are presented in Table S2, † where s 1 , s 2 and s 3 represent the hole transfer time, electron-hole pair recombination time and defect capture time, respectively. 10 Through calculations, the hole transfer rates are 4.5 × 10 9 s −1 (perovskite/Spiro-OMeTAD) and 5.3 × 10 9 s −1 (NaDTEperovskite/Spiro-OMeTAD). This is consistent with the differences in photoluminescence intensity we observed earlier (Fig.…”

“…[1][2][3][4] Perovskite not only possesses good bandgap tunability, 5 high carrier transfer rate, 6 low exciton binding energy, 7 and long exciton diffusion length, 8 but it also offers advantages such as facile solution processing and low-temperature fabrication. 9,10 Due to its unique photoelectric characteristics, it also has wide applications in LEDs, photodetectors and sensors. [11][12][13] However, the stability of perovskite solar cells remains a signicant challenge and needs to be addressed before practical application.…”

Efficient and Stable Inverted Perovskite Solar Cell using Potassium Fluoroborate Doped PEDOT:PSS

“…[28] The enhanced optical absorption of the perovskite film can be attributed to the larger grain size and better crystallinity of the perovskite grown on the film. [20,21,28,29] Increased optical absorption leads to the generation of more electron-hole pairs in the perovskite, contributing to improved performance of perovskite solar cells.…”

“…This work provides a simple and effective method to solve the problem of low hole transport in inverted devices with PEDOT:PSS as the hole transport layer. [19][20][21] 2. Results and Discussion The XPS full spectra of PEDOT:PSS and 2-KBF 4 -PEDOT:PSS are presented in Figure 1a.…”

“…This work provides a simple and effective method to solve the problem of low hole transport in inverted devices with PEDOT:PSS as the hole transport layer. [ 19–21 ]…”