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The energy loss (Eloss) caused by inefficient charge transfer and large energy level offset at the buried interface can easily restrict the performance of p-i-n perovskite solar cells (PVSCs). In this study, the utilization of poly-TPD and P3CT-N as a dual-hole transporting layer (HTLs) was implemented in a sequential manner. This approach aimed to improve the charge transfer efficiency of the HTL and mitigate charge recombination at the interface between the HTL and PVK. The results showed that this strategy also could achieve more suitable energy levels, improve the quality of the perovskite film layer, and ultimately enhance the device's stability. IPVSCs employing the dual-HTLs approach exhibited the highest power conversion efficiency of 19.85%, and the open-circuit voltage increased to 1.09 V from 1.00 V. This study offers a straightforward and efficient approach to boost the device performance by minimizing Eloss and reducing the buried interfacial defects. The findings underscore the potential of employing a dual-HTL strategy as a promising pathway for further advancements in PVSCs. [ABSTRACT FROM AUTHOR]

Perovskite light‐emitting diodes (PeLEDs) are emerging candidates for the applications of solution‐processed full‐color displays. However, the device performance of deep‐blue PeLED still lags far behind that of their red and green counterparts, which is largely limited by low external quantum efficiency (EQE) and poor operational stability. Here, a facile and reliable crystallization strategy for perovskite grains is proposed, with improved deep‐blue emission through rational interfacial engineering. By modifying the substrate with potassium cation (K+) as the supplier of heterogeneous nucleation seeds, the interfacial K+‐guided grain growth is realized for well‐packed perovskite assemblies with high surface coverage and the controlled crystal orientation, leading to the enhanced radiative recombination and hole‐transport capabilities. Synergistical boost in device performance is achieved for deep‐blue PeLEDs emitting at 469 nm with a peak EQE of 4.14%, a maximum luminance of 451 cd m–2, and spectrally stable color coordinates of (0.125, 0.076) that matches well with the National Television System Committee (NTSC) standard blue. [ABSTRACT FROM AUTHOR]

Ag2CrO4 nanoparticles (10–35 nm) were assembled onto LaFeO3 nanoparticles (20–60 nm) via a facile chemical precipitation method to form novel Ag2CrO4–LaFeO3 heterojunction composite photocatalysts. The prepared Ag2CrO4–LaFeO3 composites were characterized by XRD, SEM, TEM, XPS, BET, UV-vis DRS, PL spectroscopy and EIS and photocurrent response. The TEM result clearly shows that Ag2CrO4 particles are decorated onto LaFeO3 particles to form Ag2CrO4–LaFeO3 heterojunction. Compared to bare LaFeO3, the 10%Ag2CrO4-LaFeO3 composite exhibits a slightly increased BET specific surface area, increased photocurrent density, decreased charge-transfer resistance and decreased PL emission peaks. Using simulated sunlight as the light source and in the presence of H2O2, the photo-Fenton performance of the composite photocatalysts toward the degradation of RhB was investigated, revealing that they manifest significantly enhanced photo-Fenton degradation of RhB when compared with bare LaFeO3 and Ag2CrO4. Among the composite photocatalysts, 10%Ag2CrO4–LaFeO3 exhibits the highest photo-Fenton activity, which is about 3.1 and 2.5 times higher than that of bare LaFeO3 and Ag2CrO4, respectively. This is attributed to the fact that the composite photocatalysts have highly efficient separation of photogenerated electron–hole pairs due to the formation of Ag2CrO4–LaFeO3 heterojunctions. Active species trapping experiments and ·OH detection experiments were carried out, from which it is concluded that ·OH radicals are the dominant reactive species causing the dye degradation. A synergistic mechanism was proposed to elucidate the enhanced photo-Fenton activity of Ag2CrO4–LaFeO3 heterojunction composites. [ABSTRACT FROM AUTHOR]

The energy loss (Eloss) caused by inefficient charge transfer and large energy level offset at the buried interface can easily restrict the performance of p-i-n perovskite solar cells (PVSCs). In this study, the utilization of poly-TPD and P3CT-N as a dual-hole transporting layer (HTLs) was implemented in a sequential manner. This approach aimed to improve the charge transfer efficiency of the HTL and mitigate charge recombination at the interface between the HTL and PVK. The results showed that this strategy also could achieve more suitable energy levels, improve the quality of the perovskite film layer, and ultimately enhance the device's stability. IPVSCs employing the dual-HTLs approach exhibited the highest power conversion efficiency of 19.85%, and the open-circuit voltage increased to 1.09 V from 1.00 V. This study offers a straightforward and efficient approach to boost the device performance by minimizing Eloss and reducing the buried interfacial defects. The findings underscore the potential of employing a dual-HTL strategy as a promising pathway for further advancements in PVSCs.

Ag 2 CrO 4 nanoparticles (10-35 nm) were assembled onto LaFeO 3 nanoparticles (20-60 nm) via a facile chemical precipitation method to form novel Ag 2 CrO 4 -LaFeO 3 heterojunction composite photocatalysts. The prepared Ag 2 CrO 4 -LaFeO 3 composites were characterized by XRD, SEM, TEM, XPS, BET, UV-vis DRS, PL spectroscopy and EIS and photocurrent response. The TEM result clearly shows that Ag 2 CrO 4 particles are decorated onto LaFeO 3 particles to form Ag 2 CrO 4 -LaFeO 3 heterojunction. Compared to bare LaFeO 3 , the 10%Ag 2 CrO 4 -LaFeO 3 composite exhibits a slightly increased BET specific surface area, increased photocurrent density, decreased charge-transfer resistance and decreased PL emission peaks. Using simulated sunlight as the light source and in the presence of H 2 O 2 , the photo-Fenton performance of the composite photocatalysts toward the degradation of RhB was investigated, revealing that they manifest significantly enhanced photo-Fenton degradation of RhB when compared with bare LaFeO 3 and Ag 2 CrO 4 . Among the composite photocatalysts, 10%Ag 2 CrO 4 -LaFeO 3 exhibits the highest photo-Fenton activity, which is about 3.1 and 2.5 times higher than that of bare LaFeO 3 and Ag 2 CrO 4 , respectively. This is attributed to the fact that the composite photocatalysts have highly efficient separation of photogenerated electron-hole pairs due to the formation of Ag 2 CrO 4 -LaFeO 3 heterojunctions. Active species trapping experiments and ·OH detection experiments were carried out, from which it is concluded that ·OH radicals are the dominant reactive species causing the dye degradation. A synergistic mechanism was proposed to elucidate the enhanced photo-Fenton activity of Ag 2 CrO 4 -LaFeO 3 heterojunction composites.