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1.
Pediatr Neonatol ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38908947

RESUMO

BACKGROUND: This study aimed to analyze the use of corticosteroids and epinephrine in neonates for the first extubation attempt and compared clinical characteristics of infants with successful and failed extubation events. METHODS: This was a retrospective cohort study conducted at a single level III neonatal intensive care unit in Taiwan. The study included 215 infants born between 2020 and 2021 who had been intubated for more than 48 h before their first extubation attempt. We compared perinatal and peri-extubation characteristics and outcomes between the two groups. Successful extubation was defined as freedom from invasive ventilatory support 72 h after extubation. The relationship between corticosteroids, local epinephrine, and successful extubation was determined using multivariate logistic regression analysis. RESULTS: In the univariate analysis, the failed extubation group received a significantly higher proportion of intravenous dexamethasone (p = 0.006) than the successful extubation group. Furthermore, the failed extubation group had a longer duration of nebulized epinephrine (p = 0.034) and more episodes of local application of epinephrine to the superior larynx (p = 0.003) than the successful extubation group. Multivariate analysis revealed that the absence of lung atelectasis, tachycardia 72 h after extubation, and lower post-extubation PCO2 were the key factors associated with successful extubation. CONCLUSIONS: There were trends toward systemic dexamethasone, local application of epinephrine to the superior larynx, and longer duration of nebulized epinephrine in the reintubation group. However, corticosteroid or local epinephrine use was not significantly associated with successful extubation. Lung atelectasis, elevated levels of carbon dioxide, and tachycardia were identified as risk factors for extubation failure.

2.
Angew Chem Int Ed Engl ; 62(40): e202309831, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37594921

RESUMO

Self-assembled monolayers (SAMs) offer the advantage of facile interfacial modification, leading to significant improvements in device performance. In this study, we report the design and synthesis of a new series of carboxylic acid-functionalized porphyrin derivatives, namely AC-1, AC-3, and AC-5, and present, for the first time, a strategy to exploit the large π-moiety of porphyrins as a backbone for interfacing the indium tin oxide (ITO) electrode and perovskite active layer in an inverted perovskite solar cell (PSC) configuration. The electron-rich nature of porphyrins facilitates hole transfer and the formation of SAMs, resulting in a dense surface that minimizes defects. Comprehensive spectroscopic and dynamic studies demonstrate that the double-anchored AC-3 and AC-5 enhance SAMs on ITO, passivate the perovskite layer, and function as conduits to facilitate hole transfer, thus significantly boosting the performance of PSCs. The champion inverted PSC employing AC-5 SAM achieves an impressive solar efficiency of 23.19 % with a high fill factor of 84.05 %. This work presents a novel molecular engineering strategy for functionalizing SAMs to tune the energy levels, molecular dipoles, packing orientations to achieve stable and efficient solar performance. Importantly, our comprehensive investigation has unraveled the associated mechanisms, offering valuable insights for future advancements in PSCs.

3.
Worldviews Evid Based Nurs ; 20(5): 465-475, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37140131

RESUMO

BACKGROUND: Women usually decrease their physical activity (PA) after becoming pregnant. The change in PA may influence their symptom distress (SD). The changes and correlations between SD and PA throughout pregnancy remain unclear. AIMS: The aims of this study were to describe PA and SD trajectories across all three trimesters and examine their correlations during pregnancy. METHODS: A repeated-measure longitudinal study with convenience sampling at a hospital in Northern Taiwan was performed. Participants were recruited at 8-16 weeks of gestation, and two follow-up visits were performed at 24-28 weeks of gestation (second trimester) and after 36 weeks of gestation (third trimester). A total of 225 participants completed the study. The participants completed the Pregnancy Physical Activity Questionnaire (PPAQ) and Pregnancy-related Symptom Disturbance Scale (PSD), and sociodemographic and prenatal variables were recorded. RESULTS: Throughout pregnancy, SD decreased then increased, showing an overall upward trend, whereas PA showed the opposite pattern, increasing then decreasing, with an overall downward trend. Sedentary activity was positively correlated with both physical and psychological SD during the second and third trimesters. Exceeding the Institute of Medicine's recommendations for gestational weight gain, having childcare support, sport/exercise-type, and light-intensity PA were negatively associated with the physical and psychological SD, while a history of miscarriage and sedentary-intensity PA were positively associated with the physical and psychological SD. LINKING EVIDENCE TO ACTION: While several factors, including light-intensity PA, were found negatively associated with the physical and psychological SD, sedentary-intensity PA were positively associated with the physical and psychological SD, our findings shed light on future intervention strategies to relieve SD and decrease sedentary behavior among pregnant women.

4.
Angew Chem Int Ed Engl ; 61(39): e202209365, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35881461

RESUMO

A series of new D2h symmetric porphyrins (MDA4, MTA4, and MDA8) with donor-π-donor structures have been synthesized as the hole-transporting materials for perovskite solar cells (PSCs). The novel porphyrin molecules feature a D2h symmetrically substituted ZnII porphyrin core and two kinds of donor systems (diarylamine (DAA) and triarylamine (TAA)), which can regulate energy level, increase thermal stability, solubility, and hydrophobicity via long alkoxyl chains. PSC devices based on MDA4 as the HTM showed impressive power-conversion efficiency (PCE) of 22.67 % under AM1.5G solar illumination. Notably, the device was sent for certification, and a PCE of 22.19 % was reported, representing the highest PCE from porphyrin-based HTMs. Furthermore, the MDA4-based PSCs showed excellent thermal stability under 60 °C and RH 60 % and preserved 88 % of initial performance after 360 hours. The strategy opens a new avenue for developing efficient and stable porphyrin HTMs for PSCs.

5.
Angew Chem Int Ed Engl ; 60(9): 4886-4893, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33215788

RESUMO

A series of new double fence porphyrin dyes bJS1-bJS3, with eight long alkoxyl chains attached to four ß-phenyl groups, have been designed and synthesized. The single fence meso-substituted counterparts mJS1-mJS3 were also prepared as reference dyes. Dyes bJS1-bJS3 and mJS1-mJS3 exhibit power conversion efficiencies of 8.03-10.69 % and 2.33-6.69 %, respectively. Based on photovoltaic studies, the remarkable cell performance of double fence porphyrin sensitizers can be attributed to reduced dye aggregation and a decreased charge-recombination rate. Notably, porphyrins bJS2 and bJS3 exhibit better efficiency than the benchmark YD2-o-C8 (9.83 % in this work), demonstrating that the double fence structure is a promising design strategy for efficient porphyrin sensitizers in high-performance DSSCs.

6.
R Soc Open Sci ; 7(9): 201266, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33047067

RESUMO

This study involves the generation of gold nanoparticles (Au NPs) via a novel natural/non-toxic methodology using tea and orange-peel extracts. These were then embedded into a novel blend composed of a polyethylene oxide and gelatin (PEO-Gel) fibre mat. The scanning electron microscopy results indicated that the addition of both collagen (COL) and ascorbic acid (AA) into the PEO-Gel system (PEO-Gel-AA-COL system) enhances the Au NP incorporation into nanofibres leading to a diameter of 164.60 ± 20.95 and 192.43 ± 39.14 nm in contrast to the spraying observed with the Au PEO-Gel system alone. Releasing studies conducted over 30 min indicated that the PEO-Gel-AA-COL-orange peel Au (OpAu) system accounts for a higher content of Au release than the green tea Au (GtAu) NP system where a maximum release could be attained within 10-30 min depending on the amount of Au NPs that have been incorporated. Moreover, the transdermal diffusion studies conducted using Strat membrane indicated that Au NPs from both formulations (PEO-Gel-AA-COL-GtAu nanofibre, PEO-Gel-AA-COL-OpAu nanofibre) have diffused through the stratum corneum and trapped in the dermis and epidermis indicating its transdermal deliverability. Additionally, 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay revealed that nanofibres have similar radical scavenging activity like AA standard. Toxicity evaluation on a zebra fish embryo model confirmed that both GtAu NPs and OpAu NPs do not induce any teratogenic activity and are safe to be used in the range of 1.0-167 µg ml-1.

7.
ACS Appl Mater Interfaces ; 12(5): 5812-5819, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31942803

RESUMO

Cu(I)/(II) complex redox couples in dye-sensitized solar cell (DSSC) are of particular interest because of their low reorganization energy between Cu(I) and Cu(II), which minimizes the potential loss during sensitizer regeneration, thus allowing the open-circuit voltage of the device to go over 1.0 V. However, Cu(I)/(II)-based redox couples are reported to coordinate with 4-tert-butylpyridine (TBP), which is a standard additive in the electrolyte, and this is believed to account for the poor durability of a Cu(I)/(II)-based DSSCs. Despite TBP coordination on Cu(I)/(II) complexes are confirmed in the literature, its detailed mechanism is yet to be directly proven. In addition, how TBP coordination with Cu(I)/(II) complexes affects the stability of the device is never reported. Here, we choose bis(2,9-dimethyl-1,10-phenanthroline) copper(I)/(II) ([Cu(dmp)22+/+]) as the modeling redox couple to investigate its interaction with TBP. It is found that [Cu(dmp)2+] is resistive to TBP coordination but could form three new TBP-coordinated compounds. Moreover, it is also confirmed their electrochemical activity on Pt catalyst and mass transfer capability are both demoted significantly. As a result, serious fill factor loss is observed on the stability trail while short-circuit current density and open-circuit voltage are relatively unaffected. This unique degradation pattern may resemble a feature of Cu(I)/(II)-based redox couple after TBP poisoning.

8.
Materials (Basel) ; 12(22)2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31717944

RESUMO

This work studied the effect of niobium-content on the microstructures, hardness, and corrosion properties of CrFeCoNiNbx alloys. Results indicated that the microstructures of these alloys changed from granular structures (CrFeCoNi alloy) to the hypereutectic structures (CrFeCoNiNb0.2 and CrFeCoNi0.4 alloys), and then to the hypoeutectic microstructures (CrFeCoNiNb0.6 and CrFeCoNi alloys). The lattice constants of the major two phases in these alloys, fcc and Laves phases (hcp), increased with the increasing of Nb-content because of solid-solution strengthening. The hardness of CrFeCoNiNbx alloys also had the same tendency. Adding niobium would slightly lessen the corrosion resistance of CrFeCoNiNbx alloys in 1 M deaerated sulfuric acid and 1 M deaerated sodium chloride solutions, but the CrFeCoNiNbx alloys still had better corrosion resistance in comparison with commercial 304 stainless steel. In these dual-phased CrFeCoNiNbx alloys, the fcc phase was more severely corroded than the Laves phase after polarization tests in these two solutions.

9.
ACS Appl Mater Interfaces ; 11(24): 21424-21434, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31014067

RESUMO

The design of a dye-sensitized solar cell (DSSC) based on the simultaneous incorporation of multiple dyes is examined. By investigating the use of the porphyrin-based YD2-o-C8 and YDD6, and the organic chromophore TTAR, which can act as complementary absorbers, we are able to enhance the capture of incoming light across the solar spectrum. This is demonstrated first by using a conventional DSSC architecture with a liquid electrolyte and performed a power conversion efficiency (PCE) of 11.2%, representing an improvement over cells based on each of the independent dyes. Next, we used Cs2SnI6 as an encapsulating layer over the sensitizing molecules to reduce charge leakage across the dye layers and also added to the absorption of longer wavelengths up to one micron. Finally, we fabricated a cell utilizing a Cs2SnI6/succinonitrile solid hole-transport electrolyte and achieved a PCE of ∼8.5%. It is expected that the all solid-state design will go a long way toward improving long-term device stability.

10.
ACS Appl Mater Interfaces ; 10(46): 39970-39982, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30376713

RESUMO

In this work, we have synthesized a novel porphyrin dye named SK7, which contains two N, N-diarylamino moieties at two ß-positions as electron-donating units and one carboxy phenylethynyl moiety at the meso-position as an electron-withdrawing, anchoring group. This novel dye was tested for the application in dye-sensitized solar cells. The light-harvesting behavior of SK7 and YD2 was investigated using UV-vis absorption and density functional calculation. The electron transport properties at the TiO2/dye/electrolyte interface for SK7- and YD2-based devices were evaluated by electrochemical impedance spectroscopy. X-ray crystallographic characterization was conducted to understand the influence of two N, N-diarylamino units at two ß-positions. The power conversion efficiencies of ca. 6.54% under 1 sun illumination (AM 1.5G) and ca. 19.72% under a T5 light source were noted for the SK7 dye. The performance of SK7 is comparable to that of dye YD2, which contains only one N, N-diarylamino moiety at the meso-position (ca. 7.78 and 20.00% under 1 sun and T5 light, respectively).

11.
ACS Appl Mater Interfaces ; 10(3): 2391-2399, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29281249

RESUMO

Since their introduction, dye-sensitized solar cells (DSCs) have achieved huge success at a laboratory level. Recently, research is concentrated to visualize large DSC modules at the commercial platform. In that aspect, we have tested structurally simple porphyrin-based dye SK6 and anthracene-based dye CW10 for DSCs application under simulated 1 sun (AM 1.5G) and indoor light sources. These two dyes can be easily synthesized and yet are efficient with cell performances of ca. 5.42% and ca. 5.75% (without coadsorbent/additive) for SK6 and CW10, respectively, under AM 1.5G illumination. The power conversion efficiency (PCE) of SK6 reported in this work is the highest ever reported; this is achieved by optimizing the adsorption of SK6 on TiO2 photoanode using the most suitable solvent and immersion period. Cosensitization of SK6 with CW10 on TiO2 surface has boosted cell performance further and achieved PCE of ca. 6.31% under AM 1.5G illumination. Charge-transfer properties of individual and cosensitized devices at TiO2/dye/electrolyte interface were examined via electrochemical impedance spectroscopy. To understand the cell performances under ambient light conditions, we soaked individual and cosensitized devices under T5 and light-emitting diode light sources in the range of 300-6000 lx. The PCE of ca. 22.91% under T5 light (6000 lx) with JSC = 0.883 mA cm-2, VOC = 0.646 V, and FF = 0.749 was noted for the cosensitized device, which equals a power output of 426 µW cm-2. These results reveal that DSCs made of structurally simple dyes performed efficiently under both 1 sun (AM 1.5G) and indoor light conditions, which is undoubtedly a significant achievement when it comes to a choice of commercial application.

12.
ACS Appl Mater Interfaces ; 9(43): 37786-37796, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28990749

RESUMO

The need for low-cost and highly efficient dyes for dye-sensitized solar cells under both the sunlight and dim light environments is growing. We have devised GJ-series push-pull organic dyes which require only four synthesis steps. These dyes feature a linear molecular structure of donor-perylene-ethynylene-arylcarboxylic acid, where donor represents N,N-diarylamino group and arylcarboxylic groups represent benzoic, thienocarboxylic, 2-cyano-3-phenylacrylic, 2-cyano-3-thienoacrylic, and 4-benzo[c][1,2,5]thiadiazol-4-yl-benzoic groups. In this study, we demonstrated that a dye without tedious and time-consuming synthesis efforts can perform efficiently. Under the illumination of AM1.5G simulated sunlight, the benzothiadiazole-benzoic-containing GJ-BP dye shows the best power conversion efficiency (PCE) of 6.16% with VOC of 0.70 V and JSC of 11.88 mA cm-2 using liquid iodide-based electrolyte. It also shows high performance in converting light of 6000 lx light intensity, that is, incident power of ca. 1.75 mW cm-2, to power output of 0.28 mW cm-2 which equals a PCE of 15.79%. Interestingly, the benzoic-containing dye GJ-P with a simple molecular structure has comparable performance in generating power output of 0.26 mW cm-2 (PCE of 15.01%) under the same condition and is potentially viable toward future application.

13.
J Phys Chem Lett ; 8(8): 1824-1830, 2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-28387117

RESUMO

Indoor utilization of emerging photovoltaics is promising; however, efficiency characterization under room lighting is challenging. We report the first round-robin interlaboratory study of performance measurement for dye-sensitized photovoltaics (cells and mini-modules) and one silicon solar cell under a fluorescent dim light. Among 15 research groups, the relative deviation in power conversion efficiency (PCE) of the samples reaches an unprecedented 152%. On the basis of the comprehensive results, the gap between photometry and radiometry measurements and the response of devices to the dim illumination are identified as critical obstacles to the correct PCE. Therefore, we use an illuminometer as a prime standard with a spectroradiometer to quantify the intensity of indoor lighting and adopt the reverse-biased current-voltage (I-V) characteristics as an indicator to qualify the I-V sampling time for dye-sensitized photovoltaics. The recommendations can brighten the prospects of emerging photovoltaics for indoor applications.

14.
Molecules ; 21(8)2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27527136

RESUMO

Porphyrin YD2-o-C8-based dyes were employed to sensitize room-temperature (RT) chemical-assembled ZnO aggregated anodes for use in dye-sensitized solar cells (DSSCs). To reduce the acidity of the YD2-o-C8 dye solution, the proton in the carboxyl group of a porphyrin dye was replaced with tetrabuthyl ammonium (TBA⁺) in this work. The short-circuit current density (Jsc) of the YD2-o-C8-TBA-sensitized ZnO DSSCs is higher than that of the YD2-o-C8-sensitized cells, resulting in the improvement of the efficiency of the YD2-o-C8-based ZnO DSSCs. With an appropriate incorporation of chenodeoxycholic acid (CDCA) as coadsorbate, the Jsc and efficiency of the YD2-o-C8-TBA-sensitized ZnO DSSC are enhanced due to the improvement of the incident-photon-to-current efficiency (IPCE) values in the wavelength range of 400-450 nm. Moreover, a considerable increase in Jsc is achieved by the addition of a light scattering layer in the YD2-o-C8-TBA-sensitized ZnO photoanodes. Significant IPCE enhancement in the range 475-600 nm is not attainable by tuning the YD2-o-C8-TBA sensitization processes for the anodes without light scattering layers. Using the RT chemical-assembled ZnO aggregated anode with a light scattering layer, an efficiency of 3.43% was achieved in the YD2-o-C8-TBA-sensitized ZnO DSSC.


Assuntos
Porfirinas/química , Sistema Solar/química , Óxido de Zinco/química , Corantes/química , Fontes de Energia Elétrica , Eletrodos , Estrutura Molecular , Energia Solar
15.
Angew Chem Int Ed Engl ; 55(16): 5035-9, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-26991696

RESUMO

Despite the long list of known fluoroporphyrinoids, the most fundamental 2,3,7,8,12,13,17,18-octafluoroporphyrin (OFP) has not been synthesized until now. It is achieved by condensation of two molecules of tetrafluoro-dipyrrylmethane-2-carboxaldehyde in the presence of magnesium(II) salts. The fluorinated dipyrrylmethane also gives 5,15-bis(pentafluorophenyl)-OFP (F18P) with a reasonable yield. Both Mg/OFP and Zn/F18P in the solid-state reveal an essentially flat structure. The fluoro groups impart as much as a 0.5 V anodic shift for porphyrin ring oxidation/reduction, as well as hypsochromic shifts in the Uv-vis spectra.

16.
ACS Appl Mater Interfaces ; 8(5): 3418-27, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26752243

RESUMO

A series of zinc porphyrin dyes YD22-YD28 were synthesized and used for dye-sensitized solar cells. Dyes YD26-YD28 consist of zinc porphyrin (ZnP) as core unit, arylamine (Am) as electron-donating group, and p-ethynylbenzoic acid (EBA) as an electron-withdrawing/-anchoring group. The dyes YD22-YD25 contain additional phenylethynylene group (PE) bridged between Am and ZnP units. The influence of the PE unit on molecular properties as well as photovoltaic performances were investigated via photophysical and electrochemical studies and density functional calculations. With the insertion of PE unit, the dyes YD22-YD25 possess better light-harvesting properties in terms of significantly red-shifted Q-band absorption. The conversion efficiencies for dyes YD22-YD25 are better than those of dyes YD26-YD28 owing to larger J(SC) output. Natural transition orbitals and Mulliken charge analysis were used to analyze the electron injection efficiency for porphyrin dyes upon time-dependent DFT calculations. The results indicated that insertion of additional PE unit is beneficial to higher J(SC) by means of improved light-harvesting property due to broadened and red-shifted absorption.

17.
ACS Appl Mater Interfaces ; 7(27): 14975-82, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26083949

RESUMO

Three novel efficient donor-acceptor porphyrins, MH1-MH3, with a pyridine-type acceptor and anchoring group were synthesized and their optical, electrochemical, and photovoltaic properties investigated. Replacing the commonly used 4-carboxyphenyl anchoring group with 2-carboxypyridine, 2-pyridone, and pyridine did not significantly change the absorption and electrochemical properties of the porphyrin dyes. These new porphyrin dyes MH show power conversion efficiencies of 8.3%, 8.5%, and 8.2%, which are comparable to that of the benchmark YD2-o-C8 (η=8.25%) under similar conditions. It was demonstrated that 2-carboxypyridine is an efficient and stable anchoring group as MH1 and showed better cell performance and long-term stability than YD2-o-C8 under light soaking conditions.

18.
J Am Chem Soc ; 136(43): 15379-85, 2014 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-25299304

RESUMO

We introduce a new class of molecular iodosalt compounds for application in next-generation solar cells. Unlike tin-based perovskite compounds CsSnI3 and CH3NH3SnI3, which have Sn in the 2+ oxidation state and must be handled in an inert atmosphere when fabricating solar cells, the Sn in the molecular iodosalt compounds is in the 4+ oxidation state, making them stable in air and moisture. As an example, we demonstrate that, using Cs2SnI6 as a hole transporter, we can successfully fabricate in air a solid-state dye-sensitized solar cell (DSSC) with a mesoporous TiO2 film. Doping Cs2SnI6 with additives helps to reduce the internal device resistance, improving cell efficiency. In this way, a Z907 DSSC delivers 4.7% of energy conversion efficiency. By using a more efficient mixture of porphyrin dyes, an efficiency near 8% with photon confinement has been achieved. This represents a significant step toward the realization of low-cost, stable, lead-free, and environmentally benign next-generation solid-state solar cells.

19.
Dalton Trans ; 43(16): 6229-35, 2014 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-24599319

RESUMO

Two pentacobalt(II) EMACs were synthesized. A pyrazine-modulated tripyridyldiamine resulted in an EMAC with fully delocalized Co-Co bonds along molecules. From a pyrazine- and naphthyridine-containing ligand, a defective cobalt linear EMAC with an 8-coordinated cobalt(II) in the center was obtained for the first time. An electrochemistry study on the defective pentacobalt chain compound showed redox peaks at E1/2 = -1.00, +0.76, and +0.98 V (versus EAg/AgCl), indicating that it is quite stable and very resistant to both oxidation and reduction. Research on magnetism revealed that the fully delocalized Co EMAC is a spin mixture, and the defective cobalt EMAC showed a high-spin mononuclear cobalt(II) behaviour with a magnetic moment of 2.63 µB per molecule at room temperature. Measurement on molecular electric conductance by STM bj showed a single-molecular resistance of 15.4 (± 3.1) MΩ for defective and 12.3 (± 2.6) MΩ for delocalized pentacobalt complexes.

20.
Angew Chem Int Ed Engl ; 53(11): 2973-7, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24501108

RESUMO

Porphyrins have drawn much attention as sensitizers owing to the large absorption coefficients of their Soret and Q bands in the visible region. In a donor and acceptor zinc porphyrin we applied a new strategy of introducing 2,1,3-benzothiadiazole (BTD) as a π-conjugated linker between the anchoring group and the porphyrin chromophore to broaden the absorption spectra to fill the valley between the Soret and Q bands. With this novel approach, we observed 12.75% power-conversion efficiency under simulated one-sun illumination (AM1.5G, 100 mW cm(-2)). In this study, we showed the importance of introducing the phenyl group as a spacer between the BTD and the zinc porphyrin in achieving high power-conversion efficiencies. Time-resolved fluorescence, transient-photocurrent-decay, and transient-photovoltage-decay measurements were employed to determine the electron-injection dynamics and the lifetime of the photogenerated charge carriers.

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