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1.
Sex Transm Dis ; 50(6): e8-e10, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36863060

RESUMO

ABSTRACT: Observational studies demonstrated 30% to 40% effectiveness of outer-membrane vesicle (OMV) meningococcal serogroup B vaccines against gonorrhea. To explore whether healthy vaccinee bias influenced such findings, we examined the effectiveness of MenB-FHbp, a non-OMV vaccine that is not protective against gonorrhea. MenB-FHbp was ineffective against gonorrhea. Healthy vaccinee bias likely did not confound earlier studies of OMV vaccines.


Assuntos
Gonorreia , Vacinas Meningocócicas , Neisseria meningitidis Sorogrupo B , Humanos , Gonorreia/epidemiologia , Gonorreia/prevenção & controle , Eficácia de Vacinas , Antígenos de Bactérias
2.
MMWR Morb Mortal Wkly Rep ; 71(5152): 1610-1615, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36580416

RESUMO

As of November 14, 2022, monkeypox (mpox) cases had been reported from more than 110 countries, including 29,133 cases in the United States.* Among U.S. cases to date, 95% have occurred among males (1). After the first confirmed U.S. mpox case on May 17, 2022, limited supplies of JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic) were made available to jurisdictions for persons exposed to mpox. JYNNEOS vaccine was approved by the Food and Drug Administration (FDA) in 2019 as a 2-dose series (0.5 mL per dose, administered subcutaneously) to prevent smallpox and mpox disease.† On August 9, 2022, FDA issued an emergency use authorization to allow administration of JYNNEOS vaccine by intradermal injection (0.1 mL per dose) (2). A previous report on U.S. mpox cases during July 31-September 3, 2022, suggested that 1 dose of vaccine offers some protection against mpox (3). This report describes demographic and clinical characteristics of cases occurring ≥14 days after receipt of 1 dose of JYNNEOS vaccine and compares them with characteristics of cases among unvaccinated persons with mpox and with the vaccine-eligible vaccinated population in participating jurisdictions. During May 22-September 3, 2022, among 14,504 mpox cases reported from 29 participating U.S. jurisdictions,§ 6,605 (45.5%) had available vaccination information and were included in the analysis. Among included cases, 276 (4.2%) were among persons who had received 1 dose of vaccine ≥14 days before illness onset. Mpox cases that occurred in these vaccinated persons were associated with lower percentage of hospitalization (2.1% versus 7.5%), fever, headache, malaise, myalgia, and chills, compared with cases in unvaccinated persons. Although 1 dose of JYNNEOS vaccine offers some protection from disease, mpox infection can occur after receipt of 1 dose, and the duration of protection conferred by 1 dose is unknown. Providers and public health officials should therefore encourage persons at risk for acquiring mpox to complete the 2-dose vaccination series and provide guidance and education regarding nonvaccine-related prevention strategies (4).


Assuntos
Mpox , Vacina Antivariólica , Humanos , Masculino , Demografia , Estados Unidos/epidemiologia , Mpox/epidemiologia , Mpox/prevenção & controle
3.
Proc Natl Acad Sci U S A ; 115(34): 8523-8528, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30082396

RESUMO

Stabilized photoanodes for light-driven water oxidation have been prepared on nanoparticle core/shell electrodes with surface-stabilized donor-acceptor chromophores, a water oxidation catalyst, and an electron-transfer mediator. For the electrode, fluorine-doped tin oxide FTO|SnO2/TiO2|-Org1-|1.1 nm Al2O3|-RuP2+-WOC (water oxidation catalyst) with Org1 (1-cyano-2-(4-(diphenylamino)phenyl)vinyl)phosphonic acid), the mediator RuP2+ ([Ru(4,4-(PO3H2)2-2,2-bipyridine)(2,2-bipyridine)2]2+), and the WOC, Ru(bda)(py(CH2)(3or10)P(O3H)2)2 (bda is 2,2-bipyridine-6,6-dicarboxylate with x = 3 or 10), solar excitation resulted in photocurrents of ∼500 µA/cm2 and quantitative O2 evolution at pH 4.65. Related results were obtained for other Ru(II) polypyridyl mediators. For the organic dye PP (5-(4-(dihydroxyphosphoryl)phenyl)-10,15,20-Tris(mesityl)porphyrin), solar water oxidation occurred with a driving force near 0 V.

4.
Proc Natl Acad Sci U S A ; 114(37): 9809-9813, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28847965

RESUMO

Dye-sensitized photoelectrosynthesis cells (DSPECs) provide a flexible approach for solar water splitting based on the integration of molecular light absorption and catalysis on oxide electrodes. Recent advances in this area, including the use of core/shell oxide interfacial structures and surface stabilization by atomic layer deposition, have led to improved charge-separation lifetimes and the ability to obtain substantially improved photocurrent densities. Here, we investigate the introduction of Ag nanoparticles into the core/shell structure and report that they greatly enhance light-driven water oxidation at a DSPEC photoanode. Under 1-sun illumination, Ag nanoparticle electrodes achieved high photocurrent densities, surpassing 2 mA cm-2 with an incident photon-to-current efficiency of 31.8% under 450-nm illumination.

5.
J Chem Phys ; 150(4): 041727, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30709265

RESUMO

A mesoporous atomic layer deposition (ALD) double-shell electrode, Al2O3 (insulating core)//ALD ZnO|ALD TiO2, on a fluorine-doped tin oxide (FTO) conducting substrate was explored for a photoanode assembly, FTO//Al2O3 (insulating core)//ALD ZnO|ALD TiO2|-chromophore-catalyst, for light-driven water oxidation. Photocurrent densities at photoanodes based on mesoporous ALD double-shell (ALD ZnO|ALD TiO2|) and ALD single-shell (ALD ZnO|, ALD TiO2|) electrodes were investigated for O2 evaluation by a generator-collector dual working electrode configuration. The high photocurrent densities obtained based on the mesoporous ALD ZnO|ALD TiO2 photoanode for O2 evolution arise from a significant barrier to back electron transfer (BET) by the optimized tunneling barrier in the structure with the built-in electric field at the ALD ZnO|ALD TiO2 interface. The charge recombination is thus largely decreased. In the films, BET following injection has been investigated through kinetic nanosecond transient absorption spectra, and the results of energy band analysis are used to derive insight into the internal electronic structure of the electrodes.

6.
J Am Chem Soc ; 140(44): 15062-15069, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30371065

RESUMO

Photoanodes in dye-sensitized photoelectrosynthesis cells integrate molecular chromophore/catalyst assemblies on mesoporous n-type metal oxide electrodes for light-driven water oxidation. One limitation for sustainable photoanodes is the stability of chromophore/catalyst assembly on electrode surfaces for long periods. Progress has been made in stabilizing chromophores based on atomic layer deposition, polymer dip coating, C-C cross-coupling by electropolymerization, and silane surface binding, but little progress has been made on catalyst stabilization. We report here the silane-derivatized catalyst, Ru(bda)(L)2 (bda = 2,2'-bipyridine-6,6'-dicarboxylate, L = 4-(6-(triethoxysilyl)hexyl)pyridine), catalyst 1, which is stabilized on metal oxide electrode surfaces over an extended pH range. A surface stabilization study shows that it maintains its reactivity on the electrode surface toward electrochemical oxidation over a wide range of conditions. Its electrochemical stability on electrode surfaces has been systematically evaluated, and its role as a catalyst for water oxidation has been explored. On surfaces of mesoporous nanostructured core/shell SnO2/TiO2, with a TiO2 stabilized inner layer of the Ru(II) polypyridyl chromophore, [Ru(4,4'-(PO3H2)2bpy)(bpy)2]2+ (RuP2+; bpy = 2,2'-bipyridine), highly efficient photoelectrochemical water oxidation catalysis occurs to produce O2 with a maximum efficiency of ∼1.25 mA/cm2. Long-term loss of catalytic activity occurs with time owing to catalyst loss from the electrode surface by axial ligand dissociation in the high oxidation states of the catalyst.

7.
J Am Chem Soc ; 140(20): 6493-6500, 2018 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-29701968

RESUMO

Integration of photoresponsive chromophores that initiate multistep catalysis is essential in dye-sensitized photoelectrosynthesis cells and related devices. We describe here an approach that incorporates a chromophore assembly surface-bound to metal oxide electrodes for light absorption with an overlayer of catalysts for driving the half-reactions of water splitting. The assembly is a combination of a core-twisted perylene diimide and a ruthenium polypyridyl complex. By altering the connection sequence of the two subunits in the assembly, in their surface-binding to either TiO2 or NiO, the assembly can be tuned to convert visible light into strongly oxidizing equivalents for activation of an electrodeposited water oxidation catalyst (NiCo2O x) at the photoanode, or reducing equivalents for activation of an electrodeposited water reduction catalyst (NiMo0.05S x) at the photocathode. A key element in the design of the photoelectrodes comes from the synergistic roles of the vertical (interlayer) charge transfer and lateral (intralayer) charge hopping in determining overall cell efficiencies for photoelectrocatalysis.

8.
J Am Chem Soc ; 140(2): 719-726, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29232507

RESUMO

Water oxidation is a critical step in artificial photosynthesis and provides the protons and electrons used in reduction reactions to make solar fuels. Significant advances have been made in the area of molecular water oxidation catalysts with a notable breakthrough in the development of Ru(II) complexes that use a planar "bda" ligand (bda is 2,2'-bipyridine-6,6'-dicarboxylate). These Ru(II)(bda) complexes show lower overpotentials for driving water oxidation making them ideal for light-driven applications with a suitable chromophore. Nevertheless, synthesis of heterogeneous Ru(II)(bda) complexes remains challenging. We discuss here a new "bottom-up" synthetic method for immobilizing these catalysts at the surface of a photoanode for use in a dye-sensitized photoelectrosynthesis cell (DSPEC). The procedure provides a basis for rapidly screening the role of ligand variations at the catalyst in order to understand the impact on device performance. The best results of a water-oxidation DSPEC photoanode based on this procedure reached 1.4 mA/cm2 at pH 7 in 0.1 M [PO4H2]-/[PO4H]2-solution with minimal loss in catalytic behavior over 30 min, and produced an incident photon to current efficiency (IPCE) of 24.8% at 440 nm.

9.
J Am Chem Soc ; 140(31): 9823-9826, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30036057

RESUMO

A ruthenium polypyridyl chromophore with electronically isolated triarylamine substituents has been synthesized that models the role of tyrosine in the electron transport chain in photosystem II. When bound to the surface of a TiO2 electrode, electron injection from a Ru(II) Metal-to-Ligand Charge Transfer (MLCT) excited state occurs from the complex to the electrode to give Ru(III). Subsequent rapid electron transfer from the pendant triarylamine to Ru(III) occurs with an observed rate constant of ∼1010 s-1, which is limited by the rate of electron injection into the semiconductor. Transfer of the oxidative equivalent away from the semiconductor surface results in dramatically reduced rates of back electron transfer, and a long-lived (τ = ∼165 µs) triarylamine radical cation that has been used to oxidize hydroquinone to quinone in solution.

11.
J Am Chem Soc ; 139(23): 7685-7688, 2017 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-28558233

RESUMO

Transfer of the first electron from (Ph3P)6Cu6H6 to Cp*2Fe+ is fast (k > 106 L·mol-1·s-1). Transfer of a second electron to the same oxidant has a much lower thermodynamic driving force and is considerably slower, with k = 9.29(4) × 103 L·mol-1·s-1. The second oxidation leads to the formation of [(Ph3P)6Cu6H5]+. The structure of [(Ph3P)6Cu6H5]+ has been confirmed by its conversion back to (Ph3P)6Cu6H6 and by microanalysis; X-ray diffraction shows that the complex is a bitetrahedron in the solid state. [(Ph3P)6Cu6H5]+ can also be prepared by treating (Ph3P)6Cu6H6 with MeOTf. With less than 1 equiv of Cp*2Fe+ as oxidant, (Ph3P)6Cu6H6 gives [(Ph3P)7Cu7H6]+ as the major product; X-ray diffraction shows a Cu6 octahedron with one face capped by an additional Cu. [(Ph3P)7Cu7H6]+ can also be prepared by treating (Ph3P)6Cu6H6 with [Cu(CH3CN)4]+ (along with 1 equiv of Ph3P), and can be converted back to (Ph3P)6Cu6H6 with base/H2.

12.
J Am Chem Soc ; 139(45): 16248-16255, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-29023122

RESUMO

Organic chromophores can be synthesized by established methods and offer an opportunity to expand overall solar spectrum utilization for dye-sensitized photoelectrosynthesis cells. However, there are complications in the use of organic chromophores arising from the instability of their oxidized forms, the inability of their oxidized forms to activate a water oxidation catalyst, or the absence of a sufficiently reducing excited state for electron injection into appropriate semiconductors. Three new triarylamine donor-acceptor organic dyes have been investigated here for visible-light-driven water oxidation. They offer highly oxidizing potentials (>1 V vs NHE in aqueous solution) that are sufficient to drive a water oxidation catalyst and excited-state potentials (∼-1.2 V vs NHE) sufficient to inject into TiO2. The oxidized form of one of the chromophores is sufficiently stable to exhibit reversible electrochemistry in aqueous solution. The chromophores also have favorable photophysics. Visible-light-driven oxygen production by an organic chromophore for up to 1 h of operation has been demonstrated with reasonable faradaic efficiencies for measured O2 production. The properties of organic chromophores necessary for successfully driving water oxidation in a light-driven system are explored along with strategies for improving device performance.

13.
J Am Chem Soc ; 139(41): 14518-14525, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-28810743

RESUMO

In a dye sensitized photoelectrosynthesis cell (DSPEC), the relative orientation of the catalyst and chromophore plays an important role in determining the device efficiency. Here we introduce a new, robust atomic layer deposition (ALD) procedure for the preparation of molecular chromophore-catalyst assemblies on wide bandgap semiconductors. In this procedure, solution deposited, phosphonate derivatized metal complexes on metal oxide surfaces are treated with reactive metal reagents in the gas phase by ALD to form an outer metal ion bridging group, which can bind a second phosphonate containing species from solution to establish a R1-PO2-O-M-O-PO2-R2 type surface assembly. With the ALD procedure, assemblies bridged by Al(III), Sn(IV), Ti(IV), or Zr(IV) metal oxide units have been prepared. To evaluate the performance of this new type of surface assembly, intra-assembly electron transfer was investigated by transient absorption spectroscopy, and light-driven water splitting experiments under steady-state illumination were conducted. A SnO2 bridged assembly on SnO2/TiO2 core/shell electrodes undergoes light-driven water oxidation with an incident photon to current efficiency (IPCE) of 17.1% at 440 nm. Light-driven water reduction with a ruthenium trisbipyridine chromophore and molecular Ni(II) catalyst on NiO films was also used to produce H2. Compared to conventional solution-based procedures, the ALD approach offers significant advantages in scope and flexibility for the preparation of stable surface structures.

14.
J Urban Health ; 94(5): 716-729, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28879489

RESUMO

Neighborhood-level structural interventions are needed to address HIV/AIDS in highly affected areas. To develop these interventions, we need a better understanding of contextual factors that drive the pandemic. We used multinomial logistic regression models to examine the relationship between census tract of current residence and mode of HIV transmission among HIV-positive cases. Compared to the predominantly white high HIV prevalence tract, both the predominantly black high and low HIV prevalence tracts had greater odds of transmission via injection drug use and heterosexual contact than male-to-male sexual contact. After adjusting for current age, gender, race/ethnicity, insurance status, and most recently recorded CD4 count, there was no statistically significant difference in mode of HIV transmission by census tract. However, heterosexual transmission and injection drug use remain key concerns for underserved populations. Blacks were seven times more likely than whites to have heterosexual versus male-to-male sexual contact. Those who had Medicaid or were uninsured (versus private insurance) were 23 and 14 times more likely, respectively, to have injection drug use than male-to-male sexual contact and 10 times more likely to have heterosexual contact than male-to-male sexual contact. These findings can inform larger studies for the development of neighborhood-level structural interventions.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Características de Residência/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adulto , Etnicidade , Feminino , Infecções por HIV/etnologia , Humanos , Renda/estatística & dados numéricos , Modelos Logísticos , Masculino , Medicaid/estatística & dados numéricos , Pessoa de Meia-Idade , Grupos Raciais , Fatores Socioeconômicos , Abuso de Substâncias por Via Intravenosa/etnologia , Estados Unidos/epidemiologia
15.
J Biomed Inform ; 53: 93-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25239262

RESUMO

Travel distance to medical care has been assessed using a variety of geographic methods. Network analyses are less common, but may generate more accurate estimates of travel costs. We compared straight-line distances and driving distance, as well as average drive time and travel time on a public transit network for 1789 persons diagnosed with HIV between 2010 and 2012 to identify differences overall, and by distinct geographic areas of Philadelphia. Paired t-tests were used to assess differences across methods, and analysis of variance was used to assess between-group differences. Driving distances were significantly longer than straight-line distances (p<0.001) and transit times were significantly longer than driving times (p<0.001). Persons living in the northeast section of the city traveled greater distances, and at greater cost of time and effort, than persons in all other areas of the city (p<0.001). Persons living in the northwest section of the city traveled farther and longer than all other areas except the northeast (p<0.0001). Network analyses that include public transit will likely produce a more realistic estimate of the travel costs, and may improve models to predict medical care outcomes.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/terapia , Acessibilidade aos Serviços de Saúde , Informática Médica/métodos , Meios de Transporte , Viagem , Coleta de Dados , Sistemas de Informação Geográfica , Geografia , Humanos , Philadelphia , Software , População Urbana
16.
J Am Chem Soc ; 135(46): 17262-5, 2013 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-24171656

RESUMO

The octahedral core of 84-electron LCuH hexamers does not dissociate appreciably in solution, although their hydride ligands undergo rapid intramolecular rearrangement. The single-electron transfer proposed as an initial step in the reaction of these hexamers with certain substrates has been observed by stopped-flow techniques when [(Ph3P)CuH]6 is treated with a pyridinium cation. The same radical cation has been prepared by the oxidation of [(Ph3P)CuH]6 with Cp*2Fe(+) and its reversible formation observed by cyclic voltammetry; its UV-vis spectrum has been confirmed by spectroelectrochemistry. The 48-electron trimer [(dppbz)CuH]3 has been prepared by use of the chelating ligand 1,2-bis(diphenylphosphino)benzene (dppbz).

17.
Am J Public Health ; 103(10): 1874-81, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23947325

RESUMO

OBJECTIVES: We estimated the risk of HIV associated with sexually transmitted infection (STI) history during adolescence. METHODS: We retrospectively studied a cohort of adolescents (n = 75 273, born in 1985-1993) who participated in the Philadelphia High School STD Screening Program between 2003 and 2010. We matched the cohort to STI and HIV surveillance data sets and death certificates and performed Poisson regression to estimate the association between adolescent STI exposures and subsequent HIV diagnosis. RESULTS: Compared with individuals reporting no STIs during adolescence, adolescents with STIs had an increased risk for subsequent HIV infection (incidence rate ratio [IRR] for adolescent girls = 2.6; 95% confidence interval [CI] = 1.5, 4.7; IRR for adolescent boys = 2.3; 95% CI = 1.7, 3.1). Risk increased with number of STIs. The risk of subsequent HIV infection was more than 3 times as high among those with multiple gonococcal infections during adolescence as among those with none. CONCLUSIONS: Effective interventions that reduce adolescent STIs are needed to avert future STI and HIV acquisition. Focusing on adolescents with gonococcal infections or multiple STIs might have the greatest impact on future HIV risk.


Assuntos
Infecções por HIV/etiologia , Doenças Bacterianas Sexualmente Transmissíveis/epidemiologia , Adolescente , Criança , Atestado de Óbito , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Philadelphia/epidemiologia , Distribuição de Poisson , Vigilância da População , Estudos Retrospectivos , Medição de Risco , Distribuição por Sexo , Doenças Bacterianas Sexualmente Transmissíveis/urina , Sexo sem Proteção , Adulto Jovem
18.
Lancet Infect Dis ; 22(7): 1021-1029, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35427490

RESUMO

BACKGROUND: Declining antimicrobial susceptibility to current gonorrhoea antibiotic treatment and inadequate treatment options have raised the possibility of untreatable gonorrhoea. New prevention approaches, such as vaccination, are needed. Outer membrane vesicle meningococcal serogroup B vaccines might be protective against gonorrhoea. We evaluated the effectiveness of a serogroup B meningococcal outer membrane vesicle vaccine (MenB-4C) against gonorrhoea in individuals aged 16-23 years in two US cities. METHODS: We identified laboratory-confirmed gonorrhoea and chlamydia infections among individuals aged 16-23 years from sexually transmitted infection surveillance records in New York City and Philadelphia from 2016 to 2018. We linked gonorrhoea and chlamydia case records to immunisation registry records to determine MenB-4C vaccination status at infection, defined as complete vaccination (two MenB-4C doses administered 30-180 days apart), partial vaccination (single MenB-4C vaccine dose), or no vaccination (serogroup B meningococcal vaccine naive). Using log-binomial regression with generalised estimating equations to account for correlations between multiple infections per patient, we calculated adjusted prevalence ratios (APR) and 95% CIs to determine if vaccination was protective against gonorrhoea. We used individual-level data for descriptive analyses and infection-level data for regression analyses. FINDINGS: Between Jan 1, 2016, and Dec 31, 2018, we identified 167 706 infections (18 099 gonococcal infections, 124 876 chlamydial infections, and 24 731 gonococcal and chlamydial co-infections) among 109 737 individuals linked to the immunisation registries. 7692 individuals were vaccinated, of whom 4032 (52·4%) had received one dose, 3596 (46·7%) two doses, and 64 (<1·0%) at least three doses. Compared with no vaccination, complete vaccination series (APR 0·60, 95% CI 0·47-0·77; p<0·0001) and partial vaccination series (0·74, 0·63-0·88; p=0·0012) were protective against gonorrhoea. Complete MenB-4C vaccination series was 40% (95% CI 23-53) effective against gonorrhoea and partial MenB-4C vaccination series was 26% (12-37) effective. INTERPRETATION: MenB-4C vaccination was associated with a reduced gonorrhoea prevalence. MenB-4C could offer cross-protection against Neisseria gonorrhoeae. Development of an effective gonococcal vaccine might be feasible with implications for gonorrhoea prevention and control. FUNDING: None.


Assuntos
Infecções por Chlamydia , Gonorreia , Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis Sorogrupo B , Gonorreia/epidemiologia , Gonorreia/prevenção & controle , Humanos , Infecções Meningocócicas/prevenção & controle , Neisseria gonorrhoeae , Sorogrupo , Vacinação
19.
ChemSusChem ; 14(16): 3267-3276, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34143541

RESUMO

The development and investigation of materials that leverage unique interfacial effects on electronic structure and redox chemistry are likely to play an outstanding role in advanced technologies for wastewater treatment. Here, the use of surface functionalization of metal oxides with a RuII poly(pyridyl) complex was reported as a way to create hybrid assemblies with optimized electrochemical performance for water remediation, superior to those that could be achieved with the molecular catalyst or metal-oxide electrodes used individually. Mechanistic analysis demonstrated that the molecularly functionalized electrodes could suppress the formation of hydroxyl radicals (i. e., the dominant remediation pathway for bare metal-oxide electrodes), allowing the water remediation to proceed through the highly oxidizing Ru3+ ions in the surface-bound complexes. Furthermore, the underlying metal-oxide substrates played a crucial role in altering the electronic structure and electrochemical properties of the surface-bound catalyst, such that the competing side reaction (i. e., water splitting) was largely inhibited.

20.
Chem Commun (Camb) ; 56(81): 12130-12133, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-32960199

RESUMO

Heteroleptic copper(i) bis(phenanthroline) complexes with surface anchoring carboxylate groups have been synthesized and immobilized on nanoporous metal oxide substrates. The species investigated are responsive to the external environment and this work provides a new strategy to control charge transfer processes for efficient solar energy conversion.

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