A5052916499- Organic Electronics and Photovoltaics
- Molecular Junctions and Nanostructures
- Force Microscopy Techniques and Applications
- Surface Chemistry and Catalysis
- Conducting polymers and applications
- Thin-Film Transistor Technologies
- Quantum Dots Synthesis And Properties
- Fullerene Chemistry and Applications
- Porphyrin and Phthalocyanine Chemistry
- Semiconductor materials and devices
- Surface and Thin Film Phenomena
- Advanced Chemical Physics Studies
- Graphene research and applications
- Mechanical and Optical Resonators
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Block Copolymer Self-Assembly
- Perovskite Materials and Applications
- Semiconductor materials and interfaces
- Nanowire Synthesis and Applications
- Supramolecular Self-Assembly in Materials
- Copper-based nanomaterials and applications
- Photonic Crystals and Applications
- Spectroscopy and Quantum Chemical Studies
- Ferroelectric and Piezoelectric Materials
Institut de Ciència de Materials de Barcelona
2016-2025
FC Barcelona
2019
Instituto de Ciencia de Materiales de Sevilla
2018
Consejo Superior de Investigaciones Científicas
2000-2017
Universitat Autònoma de Barcelona
2003-2017
Centre de Recerca Matemàtica
2014
Max Planck Society
2004-2011
Max Planck Institute for Intelligent Systems
2004-2011
Karlsruhe Institute of Technology
2011
European Synchrotron Radiation Facility
2003-2011
Five core-cyanated perylene carboxylic diimides end-functionalized with fluorine-containing linear and cyclic substituents have been synthesized employed in the fabrication of air-stable n-channel organic thin-film field-effect transistors carrier mobilities up to 0.1 cm2/Vs. The relationships between molecular structure, morphology, substrate temperature during vacuum deposition, transistor performance, air stability investigated. Our experiments led us conclude that role fluorine...
The efficiency of organic bulk heterojunction solar cells strongly depends on the multiscale morphology interpenetrating polymer-fullerene network. Understanding molecular assembly and identification influencing parameters is essential for a systematic optimization such devices. Here, we investigate ordering during drying doctor-bladed blends PEDOT:PSS-coated substrates simultaneously using in situ grazing incidence X-ray diffraction (GIXD) laser reflectometry. In process blend...
In this work, we assess the possible reasons for differences observed in open circuit voltage (<italic>V</italic><sub>OC</sub>) mixed cation perovskite solar cells when comparing four different hole transport materials (HTMs), namely <bold>TAE-1</bold>, <bold>TAE-3</bold>, <bold>TAE-4</bold> and <bold>spiro-OMeTAD</bold>.
The mechanisms behind the threshold-voltage shift in organic transistors due to functionalizing of gate dielectric with self-assembled monolayers (SAMs) are still under debate. We address by which SAMs determine threshold voltage, analyzing whether voltage depends on gate-dielectric capacitance. have investigated based five oxide thicknesses and two rather diverse chemical properties, using benchmark semiconductor dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene. Unlike several previous...
We demonstrate that energy losses during friction of alkylsilane self-assembled monolayers with sharp atomic force microscope tips can be correlated to molecular events occurring at specific threshold loads. Under these loads, discrete tilts occur, which are dictated by the geometrical requirements close packing molecules. The barriers overcome tilt give rise changes in frictional forces.
Metal-organic interfaces based on copper-phthalocyanine monolayers are studied in dependence of the metal substrate (Au versus Cu), its symmetry [hexagonal (111) surfaces fourfold (100) surfaces], as well donor or acceptor semiconducting character associated with nonfluorinated perfluorinated molecules, respectively. Comparison properties these systematically varied metal-organic provides new insight into effect each previously mentioned parameters molecule-substrate interactions.
In situ X-ray measurements give insight into the effect of substrate temperature on structural evolution doctor–bladed poly(3-hexylthiophene):[6,6]-phenyl-C61 butyric acid methyl ester (P3HT:PCBM) blends during transition from wet to solid. Drying active layer at lower (10 °C) leads a better nanomorphology with finer interpenetrating network, and may be an easy route for optimization performance in solar cells. Detailed facts importance specialist readers are published as "Supporting...
Interfaces play a determining role in establishing the degree of carrier selectivity at outer contacts organic solar cells. Considering that bulk heterojunction consists blend electron donor and acceptor materials, specific relative surface coverage electrode interfaces has an impact on selectivity. This work unravels how fullerene cathode lies behind electrodes. A variety techniques such as variable-angle spectroscopic ellipsometry capacitance–voltage measurements have been used to...
Disentangling the details of vertical distribution small semiconductor molecules blended with polystyrene (PS) and contact properties are issues fundamental value for designing strategies to optimize small-molecule:polymer blend organic transistors. These questions addressed here ultrathin blends 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) PS processed by a solution-shearing technique using three different composition ratios. We show that friction force microscopy (FFM)...
The detailed structure of F16CuPc films on SiO2 has been determined by means in situ grazing incidence X-ray diffraction from the first monolayer to thicker films. In contrast homologous H16CuPc molecule, exhibit same independently deposition temperature. show a thickness-dependent polymorphism manifested in-plane crystal structure, which implies large differences molecular tilt within cofacial stacking molecules.
Self organisation: 2D binary molecular monolayers formed by co-evaporation of two small organic molecules (DIP and F16CuPc), achieve exceptional order through CF⋅⋅⋅H interactions. Room temperature STM images the “2D phase diagram” for structures versus relative coverage on Au(111) Cu(111) are shown in figure. Supporting information this article is available WWW under http://www.wiley-vch.de/contents/jc_2267/2007/z700494_s.pdf or from author. Please note: The publisher not responsible...
We report an in situ X-ray investigation of the composition dependence on structural evolution during drying doctor-bladed blends poly-(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). This study enables observation microstructure real time blend crystallization. P3HT:PCBM with ratios 1:0.5, 1:0.8, 1:2 exhibit differing course solvent evaporation resulting a different upon solidification. Large excess PCBM over eutectic impedes π−π packing P3HT chains leads to...
We have determined the full molecular 3D packing of thin organic films archetypical n-type semiconductor N, N'-dioctyl-3,4:9,10-perylene tetracarboxylic diimide (PTCDI-C 8) by surface X-ray crystallography. show that PTCDI-C 8 forms smooth layered on Al 2O 3 (11-20) with an outstanding degree order. The thin-film structure is found to consist a triclinic unit cell plane aromatic core tilted 67 +/- 2 degrees respect plane, which differs significantly from bulk structure. crystallites extend...
This structural characterisation shows how non-fullerene acceptor packing largely track from single crystals to solar cells. The crystal impacts electron mobility, while the domain purity drives bimolecular recombination and performance.
The influence of the film/substrate interface and role film thickness on structural transition temperature for thin films asymmetric BTBT derivative 7-decyl-2-phenyl[1]benzothieno[3,2-b][1]-benzothiophene (Ph-BTBT-10) have been addressed by using Kelvin probe force microscopy (KPFM) synchrotron grazing incidence wide angle X-ray scattering (GIWAXS). Our data strongly suggest that transformation from a single-layer phase to thermodynamically stable bilayer structure develops bottom its...
In organic electronics, the nature and spatial distribution of grains in polycrystalline thin films small semiconductor molecules greatly impact electronic properties devices. Therefore, tools that accurately characterize at mesoscopic level are essential. To this end, we demonstrate here power a bimodal atomic force microscopy (AFM) with torsional eigenmode for highly accurate imaging grain orientations films. The energy dissipated between tip sample during scanning depends on in-plane...
An atomic force microscope (AFM) study of the structure and stability islands alkanethiol (C16H33SH) grown on Au(111) is presented. Ripening processes involving long-range molecular diffusion takes place at ambient temperature in scale days. In partially covered surface, ripening manifested by an enlargement as well densification. On packed islands, c(4×2) superstructure imaged. Another manifestation island densification a substantial increase mechanical stability, shown resistance film to...
A study of the changes molecular packing in self-assembled monolayers alkylthiols on Au(111) induced by external pressure is presented. Atomic force microscopy (AFM) used to apply and measure height islands alkanethiols partially covering gold surface. The are made ordered straight chain alkylthiol molecules tilted from surface normal. Their was found decrease a stepwise manner as function load applied tip. Simultaneous increases friction were observed. simple geometrical model involving...
Solvent vapor annealing (SVA) can strongly influence the morphology of oligomer:fullerene based organic solar cells.
Contact resistance and charge trapping are two key obstacles, often intertwined, that negatively impact on the performance of organic field-effect transistors (OFETs) by reducing overall device mobility provoking a nonideal behavior. Here, we expose semiconductor (OSC) thin films based blends 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT-C8) with polystyrene (PS) to (i) CH3CN vapor annealing process, (ii) doping I2/water procedure, (iii) vapors I2/CH3CN simultaneously dope...
The structure and stability of alkanethiols self-assembled on Au(111) have been studied as a function the molecular chain length by means atomic force microscopy (AFM) grazing incidence X-ray diffraction (GIXD). Below saturation, phases consisting molecules with different tilt angles periodicities are formed. Differences in mechanical these revealed AFM experiments discussed terms competition between intermolecular molecule-substrate interactions length. For long molecules, play dominant...
Abstract Self‐assembly of functional supra‐molecular nanostructures is among the most promising strategies for further development organic electronics. However, a poor control interactions driving assembling phenomena still hampers tailored growth designed structures. Here exploration how non‐covalent molecule‐substrate can be modified on molecular level described. For that, mixtures DIP and F16CuPc, two molecules with donor acceptor character, respectively are investigated. A detailed study...
We report direct experimental evidence for a layer-dependent step-edge barrier in organic thin film growth, investigating di-indenoperylene on ${\mathrm{SiO}}_{2}$ as an archetypical system. In particular, we show that noticeable Ehrlich-Schw\"obel effect emerges only beyond the 3rd molecular layer, accompanied by mass step-upward diffusion. further disclose this thickness dependence of interlayer transport is directly related to reorientations during first stages growth. This ultimately...
Abstract The lack of long‐term stability in thin films organic semiconductors can often be caused by the low structural metastable phases that are frequently formed upon deposition on a substrate surface. Here, 2,7‐dioctyloxy[1]benzothieno[3,2‐ b ]benzothiophene (C 8 O‐BTBT‐OC ) and blends this material with polystyrene solution shearing fabricated. Both types exhibit surface‐induced herringbone phase (SIP) all tested coating conditions. blended reveal higher device performance field‐effect...