RESUMO
Perovskite thin films directly impact solar cell properties, making defect reduction crucial in perovskite solar cell research. In our study, we used perovskite quantum dots in the anti-solvent to act as nucleation centers in MAPbI3 thin films. These centers had lower nucleation barriers than homogeneous nucleation, improving perovskite crystallinity, reducing defects, and extending carrier lifetime. Fine-tuning the energy band also enhanced carrier transport. The most effective results were obtained using CsPb(Br0.5 I0.5)3 perovskite quantum dots. The resulting device, ITO/SnO2/MAPbI3 (300 nm)/spiro-OMeTAD (200 nm)/Ag (100 nm), achieved a 12.88% power conversion efficiency, a 16% increase from the standard element. The modified device maintained approximately 95% of its efficiency over 100 h in a 70% humidity environment.
RESUMO
Truncated silver nanodecahedrons (TAgNDs) and truncated silver nanoplates (TAgNPs) fabricated via chemical reduction and photochemical methods were added to poly[3,4-ethylenedioxythiophene]:poly[styrenesulfonate] (PEDOT:PSS) as dopants to promote the luminous efficiency of blue-emitting polymer light-emitting diodes (PLEDs). The differences in shape between TAgNDs and TAgNPs result in better dispersion of TAgNDs in PEDOT:PSS. Therefore, at an optimal doping concentration (the distributed density in the light-emitting region is 6.88 µg cm-2 for TAgNDs and 5.16 µg cm-2 for TAgNPs), the average current efficacy and maximum electroluminescence intensity enhancement factor for TAgND-doped PLEDs were 4.18 cd A-1 and 420%, respectively, which are much higher than those for TAgNP-doped PLEDs (1.83 cd A-1 and 200%) at a luminescence wavelength of 440 nm.
RESUMO
This study presents a substantial enhancement in electroluminescence achieved by depositing Ag nanoparticles on an ITO-coated glass substrate (Ag/ITO) for approximately 10-s to form novel window materials for use in polymer light-emitting diodes (PLEDs). The PLEDs discussed herein are single-layer devices based on a poly[9,9-dioctylfluorene-co-benzothiadiazole] (F8BT) emissive layer. In addition to its low cost, this novel fabrication method can effectively increase the charge transport properties of the active layer to meet the high performance requirements of PLEDs. Due to the increased conductivity and work function of the Ag/ITO substrate, the electroluminescence intensity was increased by nearly 3.3-fold compared with that of the same PLED with a bare ITO substrate.
RESUMO
Conducting atomic force microscopy and scanning surface potential microscopy were used to study the local electrical properties of gallium-doped zinc oxide (GZO) films prepared by pulsed laser deposition (PLD) on a polyimide (PI) substrate. For a PLD deposition process time of 8 min, the root-mean-square roughness, coverage percentage of the conducting regions, and mean work function on the GZO surface were 2.33 nm, 96.6%, and 4.82 eV, respectively. When the GZO/PI substrate was used for a polymer light-emitting diode (PLED), the electroluminescence intensity increased by nearly 20% compared to a standard PLED, which was based on a commercial-ITO/glass substrate.
RESUMO
An ultra-thin NaF film was thermally deposited between ITO and NPB as the buffer layer and then treated with the ultraviolet (UV) ozone, in the fabrication of organic light emitting diodes (ITO/NaF/NPB/Alq(3)/LiF/Al) to study its effect on hole-injection properties. The treatment drastically transforms the role of NaF film from hole-blocking to hole-injecting. This transformation is elucidated using hole-only devices, energy band measurement, surface energy, surface polarity, and X-ray photoelectron spectra. With the optimal thickness (3 nm) of the UV-ozone-treated NaF layer, the device performance is significantly improved, with a turn-on voltage, maximum luminance, and maximum current efficiency of 2.5 V, 15700 cd/m(2), and 4.9 cd/A, respectively. Results show that NaF film is not only a hole-blocking layer, but also a promising hole-injecting layer after UV-ozone treatment.