Cobalt Electrolyte/Dye Interactions in Dye-Sensitized Solar Cells: A Combined Computational and Experimental Study

Mosconi, Edoardo,Yum, Jun-Ho,Kessler, Florian,Gó,mez Garcí,a, Carlos J.,Zuccaccia, Cristiano,Cinti, Antonio,Nazeeruddin, Mohammad K.,Grä,tzel, Michael,De Angelis, Filippo American Chemical Society 2012 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.134 No.47

<P>We report a combined experimental and computational investigation to understand the nature of the interactions between cobalt redox mediators and TiO<SUB>2</SUB> surfaces sensitized by ruthenium and organic dyes, and their impact on the performance of the corresponding dye-sensitized solar cells (DSSCs). We focus on different ruthenium dyes and fully organic dyes, to understand the dramatic loss of efficiency observed for the prototype Ru(II) N719 dye in conjunction with cobalt electrolytes. Both N719- and Z907-based DSSCs showed an increased lifetime in iodine-based electrolyte compared to the cobalt-based redox shuttle, while the organic D21L6 and D25L6 dyes, endowed with long alkoxy chains, show no significant change in the electron lifetime regardless of employed electrolyte and deliver a high photovoltaic efficiency of 6.5% with a cobalt electrolyte. Ab initio molecular dynamics simulations show the formation of a complex between the cobalt electrolyte and the surface-adsorbed ruthenium dye, which brings the [Co(bpy)<SUB>3</SUB>]<SUP>3+</SUP> species into contact with the TiO<SUB>2</SUB> surface. This translates into a high probability of intercepting TiO<SUB>2</SUB>-injected electrons by the oxidized [Co(bpy)<SUB>3</SUB>]<SUP>3+</SUP> species, lying close to the N719-sensitized TiO<SUB>2</SUB> surface. Investigation of the dye regeneration mechanism by the cobalt electrolyte in the Marcus theory framework led to substantially different reorganization energies for the high-spin (HS) and low-spin (LS) reaction pathways. Our calculated reorganization energies for the LS pathways are in excellent agreement with recent data for a series of cobalt complexes, lending support to the proposed regeneration pathway. Finally, we systematically investigate a series of Co(II)/Co(III) complexes to gauge the impact of ligand substitution and of metal coordination (tris-bidentate vs bis-tridentate) on the HS/LS energy difference and reorganization energies. Our results allow us to trace structure/property relations required for further development of cobalt electrolytes for DSSCs.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2012/jacsat.2012.134.issue-47/ja3079016/production/images/medium/ja-2012-079016_0016.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja3079016'>ACS Electronic Supporting Info</A></P>

Land Subsidence in Oil&Gas Activities: Analysis and Monitoring with an Integrated Approach

( Alice Pozzoli ),( Alessandro Mosconi ),( Stefano Gagliano ),( Alberto Meroni ) 대한지질공학회 2019 대한지질공학회 학술발표회논문집 Vol.2019 No.2

Monitoring of soil compaction in Oil&Gas industry is worth in those areas where the hydrocarbon extraction goes along with either important natural land subsidence and soil deformation due to human activities such as building constructions, infrastructural implementations rather than fluid extractions and withdrawals. Monitoring the resulting vertical displacement is crucial for health and safety management, due to the potential impact on both people and environment. The possibility to integrate data collected from different instruments coming out with a fast and reliable analysis and interpretation is necessary to support decision making. The direct access to analyzed data through remote control would help to enforce prompt and tailored decisions enabling the optimization of anthropic activities vs natural land subsidence. Eni thanks to its extended technological know-how has been continuously developing innovative and integrated methodologies in order to analyze and interpret any acquired soil deformation parameter. To this purpose, thanks to a collaboration with Harris Geospatial Solution, ePISAV, an ENVI extension, has been customized, able to capitalize on and combine all the different data collected in different surveys. The workflow has been applied to an onshore site, enabling a complex study on land subsidence integrating monitoring parameters as InSAR, CGPS and shallow compaction data. Moreover, a quantitative comparison has been performed between collected measurements and the predictive subsidence model developed in house, allowing a proper calibration of the geomechanical model.

Current Challenges for the Early Detection of Alzheimer’s Disease: Brain Imaging and CSF Studies

Rachel Mistur,Lisa Mosconi,Susan De Santi,Marla Guzman,Yi Li,Wai Tsui,Mony J. de Leon 대한신경과학회 2009 Journal of Clinical Neurology Vol.5 No.4

The development of prevention therapies for Alzheimer’s disease (AD) would greatly benefit from biomarkers that are sensitive to the subtle brain changes that occur in the preclinical stage of the disease. Reductions in the cerebral metabolic rate of glucose (CMRglc), a measure of neuronal function, have proven to be a promising tool in the early diagnosis of AD. In vivo brain 2-[ 18 F]fluoro-2-Deoxy-D-glucose-positron emission tomography (FDG-PET) imaging demonstrates consistent and progressive CMRglc reductions in AD patients, the extent and topography of which correlate with symptom severity. There is increasing evidence that hypometabolism appears during the preclinical stages of AD and can predict decline years before the onset of symptoms. This review will give an overview of FDG-PET results in individuals at risk for developing dementia, including: presymptomatic individuals carrying mutations responsible for early-onset familial AD; patients with Mild Cognitive Impairment (MCI), often a prodrome to late-onset sporadic AD; non-demented carriers of the Apolipoprotein E (ApoE) ε4 allele, a strong genetic risk factor for late-onset AD; cognitively normal subjects with a family history of AD; subjects with subjective memory complaints; and normal elderly followed longitudinally until they expressed the clinical symptoms and received post-mortem confirmation of AD. Finally, we will discuss the potential to combine different PET tracers and CSF markers of pathology to improve the early detection of AD.

Neutron Studies for Dating the Universe

F. Kappeler,A. Mengoni,M. Mosconi,K. Fujii,M. Heil,C. Domingo-pardo,The n_TOF Collaboration 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23

The neutron capture cross sections of ^(186)Os and ^(187)Os are of key importance for defining the s-process abundance of ^(187)Os at the formation of the solar system. This quantity can be used to determine the radiogenic abundance component of ^(187)Os from the decay of ^(187)Re (t_(1/2) = 41.2 Gyr) and to infer the time-duration of the nucleosynthesis in our galaxy (Re/Os cosmochronometer). The neutron capture cross sections of ^(186)Os, ^(187)Os, and ^(188)Os have been measured at the CERN n_TOF facility from 1 eV to 1 MeV, covering the entire energy range of astrophysical interest. From these data Maxwellian averaged capture cross sections have been calculated with uncertainties between 3.3 and 4.7%. Additional information was obtained by measuring the inelastic scattering cross section of ^(187)Os at the Karlsruhe 3.7 MV Van de Graaff accelerator and by neutron resonance analyses of the n TOF capture data to establish a comprehensive experimental basis for the Hauser-Feshbach statistical model. Consistent HF calculations for the capture and inelastic reaction channels were performed to determine the stellar enhancement factors, which are required to correct the Maxwellian averaged cross sections for the effect of thermally populated excited states. The consequences of this analysis for the s-process component of the ^(187)Os abundance and the related impact on the evaluation of the time-duration of Galactic nucleosynthesis via the Re/Os cosmo-chronometer are discussed.

High open-circuit voltage solid-state dye-sensitized solar cells with organic dye.

Chen, Peter,Yum, Jun Ho,De Angelis, Filippo,Mosconi, Edoardo,Fantacci, Simona,Moon, Soo-Jin,Baker, Robin Humphry,Ko, Jaejung,Nazeeruddin, Md K,Grä,tzel, Michael American Chemical Society 2009 NANO LETTERS Vol.9 No.6

<P>Solid-state dye-sensitized solar cells were fabricated using an organic dye, 2-cyanoacrylic acid-4-(bis-dimethylfluoreneaniline)dithiophene (JK2), which exhibits more than 1 V open-circuit potential (V(oc)). To scrutinize the origin of high voltage in these cells, transient V(oc) decay measurements and density functional theroy calculations of the interacting dye/semiconductor surface were performed. A negative conduction band shift was observed due to the favorable dipolar field exerted by the JK2 sensitizer to the TiO(2) surface, at variance with heteroleptic Ru(II)-dyes for which an opposite dipole effect was found, providing an increased V(oc).</P>

Nearly Monodisperse Insulator Cs ₄ PbX ₆ (X = Cl, Br, I) Nanocrystals, Their Mixed Halide Compositions, and Their Transformation into CsPbX ₃ Nanocrystals

Akkerman, Quinten A.,Park, Sungwook,Radicchi, Eros,Nunzi, Francesca,Mosconi, Edoardo,De Angelis, Filippo,Brescia, Rosaria,Rastogi, Prachi,Prato, Mirko,Manna, Liberato American Chemical Society 2017 NANO LETTERS Vol.17 No.3

<P/><P>We have developed a colloidal synthesis of nearly monodisperse nanocrystals of pure Cs<SUB>4</SUB>PbX<SUB>6</SUB> (X = Cl, Br, I) and their mixed halide compositions with sizes ranging from 9 to 37 nm. The optical absorption spectra of these nanocrystals display a sharp, high energy peak due to transitions between states localized in individual PbX<SUB>6</SUB><SUP>4–</SUP> octahedra. These spectral features are insensitive to the size of the particles and in agreement with the features of the corresponding bulk materials. Samples with mixed halide composition exhibit absorption bands that are intermediate in spectral position between those of the pure halide compounds. Furthermore, the absorption bands of intermediate compositions broaden due to the different possible combinations of halide coordination around the Pb<SUP>2+</SUP> ions. Both observations are supportive of the fact that the [PbX<SUB>6</SUB>]<SUP>4–</SUP> octahedra are electronically decoupled in these systems. Because of the large band gap of Cs<SUB>4</SUB>PbX<SUB>6</SUB> (>3.2 eV), no excitonic emission in the visible range was observed. The Cs<SUB>4</SUB>PbBr<SUB>6</SUB> nanocrystals can be converted into green fluorescent CsPbBr<SUB>3</SUB> nanocrystals by their reaction with an excess of PbBr<SUB>2</SUB> with preservation of size and size distributions. The insertion of PbX<SUB>2</SUB> into Cs<SUB>4</SUB>PbX<SUB>6</SUB> provides a means of accessing CsPbX<SUB>3</SUB> nanocrystals in a wide variety of sizes, shapes, and compositions, an important aspect for the development of precisely tuned perovskite nanocrystal inks.</P>

Method Developing and Testing for Inelastic Scattering Measurements at the GELINA Facility

A. Plompen,N. Nankov,C. Rouki,M. Stanoiu,C. Borcea,D. Deleanu,A. Negret,P. Dessagne,M. Kerveno,G. Rudolf,J. C. Thiry,M. Mosconi,R. Nolte 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23

Accurate inelastic scattering measurements are of interest to improving modelling and simulation of advanced reactor systems through better nuclear data (OECD-NEA, High priority request list for nuclear data http://www.nea.fr/html/dbdata/hprl/). Two setups are available at IRMM for measurements of inelastic scattering with the (n; n´γ)-technique. The first the GAINS gammaarray for inelastic neutron scattering at a 200 m station consists of eight high purity germanium detectors, has high incident neutron energy resolution and is therefore tailored for inelastic scattering measurements. The second, at a 30 m station was developed by IPHC with the purpose of studying actinides for the Th/U cycle and emphasizing besides (n, n´γ) also (n, 2nγ) reactions. In the recent past a number of efforts were started to investigate the uncertainties and corrections required to obtain reliable results and to investigate the limits of accuracy of this technique. A joint effort is described that has led to an improved understanding of the fission chambers used. In particular, the important corrections to the efficiency for fission fragment loss were investigated.

Olaparib plus bevacizumab as maintenance therapy in patients with newly diagnosed, advanced ovarian cancer: Japan subset from the PAOLA-1/ENGOT-ov25 trial

Keiichi Fujiwara,Hiroyuki Fujiwara,Hiroyuki Yoshida,Toyomi Satoh,Kan Yonemori,Shoji Nagao,Takashi Matsumoto,Hiroaki Kobayashi,Hughes Bourgeois,Philipp Harter,Anna Maria Mosconi,Isabel Palacio Vazquez 대한부인종양학회 2021 Journal of Gynecologic Oncology Vol.32 No.5

Objective: The addition of maintenance olaparib to bevacizumab demonstrated a significant progression-free survival (PFS) benefit in patients with newly diagnosed, advanced ovarian cancer in the PAOLA-1/ENGOT-ov25 trial (NCT02477644). We evaluated maintenance olaparib plus bevacizumab in the Japan subset of PAOLA-1. Methods: PAOLA-1 was a randomized, double-blind, phase III trial. Patients received maintenance olaparib tablets 300 mg twice daily or placebo twice daily for up to 24 months, plus bevacizumab 15 mg/kg every 3 weeks for up to 15 months in total. This prespecified subgroup analysis evaluated investigator-assessed PFS (primary endpoint). Results: Of 24 randomized Japanese patients, 15 were assigned to olaparib and 9 to placebo. After a median follow-up for PFS of 27.7 months for olaparib plus bevacizumab and 24.0 months for placebo plus bevacizumab, median PFS was 27.4 versus 19.4 months, respectively (hazard ratio [HR]=0.34; 95% confidence interval [CI]=0.11–1.00). In patients with tumors positive for homologous recombination deficiency, the HR for PFS was 0.57 (95% CI=0.16–2.09). Adverse events in the Japan subset were generally consistent with those of the PAOLA-1 overall population and with the established safety and tolerability profiles of olaparib and bevacizumab. Conclusion: Results in the Japan subset of PAOLA-1 support the overall conclusion of the PAOLA-1 trial demonstrating that the addition of maintenance olaparib to bevacizumab provides a PFS benefit in patients with newly diagnosed, advanced ovarian cancer. Trial Registration: ClinicalTrials.gov Identifier: NCT02477644