In this study, ultraviolet (UV)-ozone treated ultrathin Nb-doped ZnO (NZO) films are developed as an efficient anode buffer layer to improve the overall performance of organic light-emitting diodes ...(OLEDs). The results show that the UV-ozone treated NZO buffer layer containing 1 mol% of Nb2O5 possesses a higher oxygen content and a greater work function (5.22 eV) as compared to that of an indium tin oxide (ITO) film (~4.7 eV) signifying a reduction in hole injection barrier and thus an improvement in the injection efficiency. In addition, UV-ozone treatment can increase the surface energy of NZO films while reducing their surface roughness. Importantly, the UV-ozone treated 1 nm-thick NZO film with a Nb2O5 doping concentration of 1 mol% can help to lower the turn-on voltage from 3.2 V to 2.8 V, increase the luminance from 10,450 cd/m2 to 25370 cd/m2, and improve the current efficiency from 3.46 cd/A to 5.26 cd/A, (~52 % enhancement as compared to the standard OLED device). Moreover, OLEDs with the developed buffer layer reveal a significant improvement in the roll-off phenomenon under high current densities, indicating a key role of the optimized NZO film in enhancing the carrier balance of the devices. When applied to the p-i-n structure, the NZO film also lead to a superior device performance as compared to the conventional p-i-n structure using NPB:MoO3 as a hole injection layer, suggesting a widespread use of the developed thin film. These findings therefore show a promising use of the UV-ozone treated NZO ultrathin film as an effective anode buffer material for enhancing OLED overall performance.
•Nb2O5 doping, UV-ozone surface treatment, anode buffer layer, organic light-emitting diodes (OLED).
Air annealing of MoO3 bottom layer is a simple and highly efficient surface treatment method to prepare ultrathin, continuous, and smooth Ag layers in MoO3/Ag/MoO3 (MAM) transparent conductive films ...(TCFs) for indium tin oxide (ITO)-free organic solar cells (OSCs). Air annealing can readily oxidize MoO3 surface and increase surface energy of the MoO3 layer, which significantly enhances the adhesion between Ag and MoO3. When the MoO3 bottom layer is annealed at 200 °C, moreover, the treatment yields a flatter MoO3 surface, which positively influences the growth of Ag nanostructures. Eventually, an almost homogeneous, smooth, and continuous surface morphology of the ultrathin Ag films with a thickness of 6.5 nm was obtained. By employing air-annealed MoO3 bottom layer, the MoO3 (200 °C, 10 min)/Ag (6.5 nm)/MoO3 TCF had higher optical transmittance (Tav = 83.6%) and lower sheet resistance (Rs = 6.5 Ω/sq) than unannealed MAM or commercial ITO TCFs, thereby obtaining the higher value of figure of merit (FTC = 2.6 ×10−2 Ω−1). When used as the transparent electrode in organic solar cells (OSCs), the improved optoelectrical properties of the MoO3 (200 °C, 10 min)/Ag (6.5 nm)/MoO3 electrode result in increased short-circuit current density (Jsc = 2.27 mA cm−2) and fill factor (FF = 54.8%) of OSCs in comparison to devices based on unannealed MAM and ITO electrodes, leading to an improvement in power conversion efficiency (PCE = 0.62%). From the results of photocurrent measurements, air annealing MoO3 increases exciton generation in active layers and reduces the carrier back-transfer induced recombination at the anode contact, yielding the enhanced photovoltaic performance.
Display omitted
•Air annealing of MoO3 can oxidize MoO3 surface and increase surface energy of the MoO3 layer.•An almost smooth, and continuous surface morphology of the ultrathin Ag films was obtained by air annealing MoO3.•Air annealing of the MoO3 layer increases the figure of merit of MoO3/Ag/MoO3 (MAM) transparent conductive films (TCFs).•Air-annealed MAM-based organic solar cells (OSCs) exhibit the enhanced photovoltaic performance.•Air annealing of MoO3 in MAM TCFs increases exciton generation and reduces carrier recombination in OSCs.
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.
•Electro-deposited CuSCN was used for the hole injection layer in OLEDs.•The effects of applying thermal annealing and UV-Ozone treatments on CuSCN/organic interface were investigated.•Surface ...energy, polarity, morphology characteristics were improved owing to interface dipole-dipole effects of applied treatments.•Utilization of both treatment led to a remarkable enhancement of OLED performances.
In this study, we demonstrated an organic light-emitting diode (OLED) using electro-deposited CuSCN as a hole-injection layer. The effects of thermal annealing and UV-Ozone treatments on ITO/CuSCN/organic interfaces were investigated. By employing both UV-O3 and proper thermal annealing (75 ° C, 20 min), Cu2O was found on the surface of CuSCN. With these treatments, the surface roughness of the organic deposited on CuSCN was reduced from 4.25 to 1.28 nm. The optical transmittance was also enhanced. Additionally, the CuSCN surface energy and polarity were considerably increased and the hole-injection barrier was decreased from 0.70 to 0.47 eV. The interface dipole effects lead to better adhesion between CuSCN/organic interface and facilitate the hole injection capability from anode ITO due to the formation of superficial Cu2O. The underlying mechanisms were illustrated by surface energy, X-Ray photoelectron spectroscopy (XPS), and ultraviolet photoelectron spectroscopy (UPS) measurements. As a result, these significantly enhanced CuSCN characteristics led to improved OLED performances, which achieved a hundred-fold efficiency compared to the device without any treatment. With this realization of integrating electro-deposited CuSCN into conventional organic optoelectronic systems, it could bring various practical benefits particularly concerning industrial interests in low-temperature, cost-effective, and large-area fabrication techniques.
Ultraviolet ozone (UVO) treatment of molybdenum trioxide (MoO3) appears to be a simple and efficient method for obtaining highly continuous and smooth silver (Ag) thin films in the thermally ...evaporated MoO3/Ag/MoO3 (MAM) multilayered structure as transparent electrodes for small-molecule organic solar cells (OSCs). It is observed that UVO treatment can oxidatively modify the non-stoichiometric MoO3 (or MoO3-x) surfaces, further increasing the Mo6+/Mo5+ composition ratio and work function of MoO3-x. Importantly, the use of UVO treatment for the MoO3 bottom layer effectively improves the wettability of Ag on MoO3 and enhances the lateral growth of Ag thin film, resulting in a reduction of the percolation threshold thickness of the continuous Ag layer. Due to the formation of an ultrathin Ag interlayer with a continuous and smooth surface morphology, the MAM multilayered electrode after UVO treatment of MoO3 for 3 min has excellent optical and electrical properties, including a high maximum transmittance of 89.1% and a low sheet resistance of 8.0 Ω/sq. When the optimal UVO-treated MoO3/Ag (7.5 nm)/MoO3 films are used as the anode in OSCs with the copper phthalocyanine (CuPc)/fullerene (C60) planar heterojunction structure, the OSCs have a power conversion efficiency of 0.55%, which is 2.0 and 1.2 times higher than that of devices with untreated MoO3/Ag (7.5 nm)/MoO3 (0.27%) and MoO3/Ag (10 nm)/MoO3 electrodes (0.46%), respectively, and competitive with that of indium-tin-oxide-based devices. Because of almost full surface coverage of the Ag interlayer, UVO treatment of MoO3 in MAM multilayered electrodes can improve charge carrier injection/extraction at the anode contact and hence improve the photovoltaic performance of OSCs.
Display omitted
•Ultraviolet ozone (UVO) treatment for the MoO3 layer effectively improves the wettability of Ag on MoO3.•UVO-treated MoO3 layer decreases the percolation threshold thickness of continuous Ag films in transparent conductive films.•UVO-treated MoO3 layer increases the optical transmittance and electrical conductivity of the MoO3/Ag/MoO3 (MAM) electrodes.•The higher power conversion efficiency was obtained in UVO-treated MAM-based organic solar cells (OSCs).•UVO treatment of MoO3 in MAM multilayer electrodes improves charge carrier injection/extraction at the anode contact of OSCs.
Interleukin-6 (IL-6), a proinflammatory cytokine, was found to surge in the cerebral spinal fluid after aneurysmal subarachnoid hemorrhage (SAH). We hypothesized that the plasma level of IL-6 could ...be an independent biomarker in predicting clinical outcome of patients with ruptured intracranial aneurysm.
We prospectively included 53 consecutive patients treated with platinum coil embolization of the ruptured intracranial aneurysm. Plasma IL-6 levels were measured in the blood samples at the orifices of the aneurysms and from peripheral veins. The outcome measure was the modified Rankin Scale one month after SAH. Multiple logistic regression analyses were used to evaluate the associations between the plasma IL-6 levels and the neurological outcome.
Significant risk factors for the poor outcome were old age, low Glasgow Coma Scale (GCS) on day 0, high Fisher grades, and high aneurysmal and venous IL-6 levels in univariate analyses. Aneurysmal IL-6 levels showed modest to moderate correlations with GCS on day 0, vasospasm grade and Fisher grade. A strong correlation was found between the aneurysmal and the corresponding venous IL-6 levels (ρ = 0.721; P<0.001). In the multiple logistic regression models, the poor 30-day mRS was significantly associated with high aneurysmal IL-6 level (OR, 17.97; 95% CI, 1.51-214.33; P = 0.022) and marginally associated with high venous IL-6 level (OR, 12.71; 95% CI, 0.90-180.35; P = 0.022) after adjusting for dichotomized age, GCS on day 0, and vasospasm and Fisher grades.
The plasma level of IL-6 is an independent prognostic biomarker that could be used to aid in the identification of patients at high-risk of poor neurological outcome after rupture of the intracranial aneurysm.
The core density of the defects in perovskite thin films will directly affect the properties of perovskite solar cells. On the other hand, interface engineering is usually being used to effectively ...improve the quality of perovskite thin films. In this sought of work, MAPbI3 perovskite thin films were modified by an antisolvent process using trioctylphosphine as a passivator. Trioctylphosphine is a kind of Lewis base and from the experimental results, it is noticed on being contribute to MAPbI3 grain growth and grain boundary passivation. Due to the grain boundary passivation and grain size increase, the intense defect density inside the grain and at the grain boundary of the MAPbI3 films is gradually reduced, thereby improving the carrier lifetime, while the hydrophobic property of octyl alkane makes the perovskite thin films less susceptible to air, water and oxygen degraded by the influence. The solar cell which are using the proposed films with the device structure configuration as ITO/SnO2/MAPbI3/spiro-OMeTAD/Ag and the perovskite layers were modified with trioctylphosphine. Among them, the perovskite thin films showcased to have a best performance when the trioctylphosphine chlorobenzene solution was about 0.15% and the PCE of the device reached for about 12.17%, an increase of 10% was compared with the standard device. In addition, the modified device exhibits good environmental stability, retaining about 90% of the initial efficiency for 100 h in a 70% humidity environment.
•The modification of MAPbI3 perovskite films by trioctylphosphine, which can improve the performance of the solar cell.•The results show that trioctylphosphine as a Lewis base contributes to grain growth and grain boundary passivation.•The hydrophobic properties of octyl alkanes make perovskite films less susceptible to degradation by oxygen and water.•0.15% of trioctylphosphine chlorobenzene solution is the best ratio. The PCE reaches 12.17%.•After being exposed to a humidity of 70% for 100 h, the device only experiences a 90% decrease in PCE.
Upper tract urothelial cancer (UTUC) is a less common disease in Western countries but has a high level of prevalence in Asian populations. Compared to bladder cancer, unique etiologic and genomic ...factors are involved in UTUC. Fibroblast growth factor receptor 3 (FGFR3) up-regulation has been proposed as a promising target for bladder cancer therapy. In this study, we aimed to profile the expression of FGFR3 in Asian and Caucasian UTUC tissues and to evaluate the in vitro therapeutic efficacy of small interference RNA (siRNA)-mediated FGFR3 silencing in UTUC treatment. The FGFR3 expression levels in renal pelvis tissues and microarray sections from Asian and Caucasian patients with UTUC, respectively, were measured via immunohistochemistry. The BFTC-909 and UM-UC-14 UTUC cell lines were used to examine the effects of FGFR3 silencing on proliferation, migration, epithelial-mesenchymal transition (EMT) marker expression, and signaling machinery. FGFR3 expression increased as the TNM stage increased in both Asian and Caucasian UTUC tumors, and no statistical difference was identified between the two groups. In vitro studies demonstrated that FGFR3 siRNA delivery significantly inhibited proliferation and migration and suppressed the expression of EMT markers and transcription factors in UTUC cells. Mechanistically, FGFR3 silencing alleviated the constitutive expression of RAS and the phosphorylation of MAPK signaling mediators, including ERK1/2 and JNK1/2. FGFR3 silencing elicited an apoptosis-inducing effect similar to that of FGFR inhibition. Conclusion: siRNA-targeted FGFR3 expression may impede the expansion and invasion of UTUC cells by alleviating the RAS/MAPK signaling pathway. The genetic interference of FGFR3 expression via siRNA in UTUC cells may constitute a useful therapeutic strategy.
PDF
