1,721,298 research outputs found
Synthesis and excited state processes of arrays containing amine-rich carbon dots and unsymmetrical rylene diimides
Full text linkCombining carbon dots (CDs) with p-extended chromophores is an attractive way to study the electronic and energy processes of the former as a key step to many applications, including photosensing, photocatalysis, or photosensitization. CDs, in conjugation with chromophores, can have value in preparing donor–acceptor hybrids, and can also be used as scaffolds to support electronic communication between dyes. In this work, we conjugate two different rylene diimides, naphthalene and perylene diimides (NDI and PDI, respectively), with amorphous nitrogen-doped carbon dots. We take advantage of the imidization reaction between the amine-rich surface of the carbon dots and the monimide monoanhydride precursors of NDIs and PDIs, under microwave assisted conditions. The resulting (nano)hybrids were characterized also by spectroscopic methods. In particular, time-resolved spectroscopy for the multichromophoric array, consisting of CDs and both rylene diimides, allowed us to elucidate the complex inter-chromophoric interactions taking place in the excited state.Fil: Dordevic, Luka. Università degli Studi di Trieste; ItaliaFil: Haines, Philipp. Universitat Erlangen-Nuremberg; AlemaniaFil: Cacioppo, Michele. Università degli Studi di Trieste; ItaliaFil: Arcudi, Francesca. Università degli Studi di Trieste; ItaliaFil: Scharl, Tobias. Universitat Erlangen-Nuremberg; AlemaniaFil: Cadranel, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Guldi, Dirk. Universitat Erlangen-Nuremberg; AlemaniaFil: Prato, Maurizio. Università degli Studi di Trieste; Itali
Symmetry‐Breaking Charge‐Transfer Chromophore Interactions Supported by Carbon Nanodots
Full text linkCarbon dots (CDs) and their derivatives are useful platforms for studying electron-donor/acceptor interactions and dynamics therein. Herein, we couple amorphous CDs with phthalocyanines (Pcs) that act as electron donors with a large extended p-surface and intense absorption across the visible range of the solar spectrum. Investigations of the intercomponent interactions by means of steady-state and pump-probe transient absorption spectroscopy reveal symmetry-breaking charge transfer/separation and recombination dynamics within pairs of phthalocyanines. The CDs facilitate the electronic interactions between the phthalocyanines. Thus, our findings suggest that CDs could be used to support electronic couplings in multichromophoric systems and further increase their applicability in organic electronics, photonics, and artificial photosynthesisFil: Cacioppo, Michele. Università degli Studi di Trieste; ItaliaFil: Scharl, Tobias. Universitat Erlangen-Nuremberg; AlemaniaFil: Dordevic, Luka. Università degli Studi di Trieste; ItaliaFil: Cadranel, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Arcudi, Francesca. Università degli Studi di Trieste; ItaliaFil: Guldi, Dirk. Universitat Erlangen-Nuremberg; AlemaniaFil: Prato, Maurizio. Università degli Studi di Trieste; Itali
Ultrasound-induced transformation of fluorescent organic nanoparticles from a molecular rotor into rhomboidal nanocrystals with enhanced emission
Full text linkFluorescent organic nanoparticles (FONs) based on aggregation-induced emission (AIE) are receiving increasing attention owing to their simple preparation, enhancedoptical properties, and a wide range of applications. Therefore, finding simple methods to tune the structural and emissive properties of FONs is highly desirable. In this context, we discuss the preparation of highly emissive, amorphous AIE spherical nanoparticles based on a structurally-simple molecular rotor and their sonochemicaltransformation into rhomboidal nanocrystals. Interestingly, the ultrasound-induced modification of the morphology is accompanied by a remarkable enhancement in the stability and emission of the resulting nanocrystals. Detailed characterization of both spherical and rhomboidal nanoparticles was carried out by means of several microscopic, crystallographic, and spectroscopic techniques as well as quantum mechanical calculations. In a nutshell, this work provides a unique example of the ultrasound-induced switching of morphology, stability, and emission in FONsFinancial support from Spanish Ministry of Economy and Competitivity, MICINN (CTQ-2011-24187/BQU), MIUR through FIRB program (contract no. RBFR10DAK6), ERC Advanced Grant 2012 (number 320951
Substituting TiCl4-carbon nanohorn interfaces for dye-sensitized solar cells
No full textAn easy-to-implement strategy to introduce carbon nanohorns as interlayers in the photoelectrode of a dye-sensitized solar cell without affecting its overall performance is presented. This provides a clean, easy, and ecofriendly alternative to achieve highly efficient cells
Fluorinated Fullerenes: Sources of Donor-Acceptor Dyads with [18]Trannulene Acceptors for Energy- and Electron-Transfer Reactions
No full text
Photon‐ and Charge‐Management in Advanced Energy Materials: Combining 0D, 1D, and 2D Nanocarbons as well as Bulk Semiconductors with Organic Chromophores
Full text linkIn this contribution, seminal works in the area of photon- and charge-management are highlighted with focus on covalent electron donor-acceptor conjugates built around porphyrins (Ps), on one hand, and 0D, 1D, and 2D nanocarbons, on the other hand. Photons in these conjugates are managed by Ps, while 0D, 1D, and 2D nanocarbons serve as the active component, which enable managing charges. With a few leading examples, it can be explored much beyond the simple photon- and charge-management characterization and emphasize photovoltaics and photocatalysis to convert and store energy. This contribution concludes by highlighting recent progress in mixing and matching the unique charge-management features of nanocarbons in the design of multidimensional nanocarbons.Fil: Cadranel, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; Argentina. Universitat Erlangen-Nuremberg; AlemaniaFil: Haines, Philipp. Universitat Erlangen-Nuremberg; AlemaniaFil: Kaur, Ramandeep. Universitat Erlangen-Nuremberg; AlemaniaFil: Menon, Arjun. Universitat Erlangen-Nuremberg; AlemaniaFil: Münich, Peter W.. Universitat Erlangen-Nuremberg; AlemaniaFil: Schol, Peter R.. Universitat Erlangen-Nuremberg; AlemaniaFil: Guldi, Dirk. Universitat Erlangen-Nuremberg; Alemani
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Optical processes in carbon nanocolloids
No full textIn recent years, carbon dots, graphene quantum dots, and other carbon nanocolloids have attracted a mounting interest as readily available, non-toxic, and tailorable carbon-based nanomaterials. One of the most fascinating features of carbon nanocolloids is their luminescence, the origin of which remains a source of dispute. The lack of understanding of the optical properties of carbon nanocolloids hampers their use in technological, environmental, and biomedical processes. Here, we review the current knowledge of excited states in carbon nanocolloids and related properties, inviting researchers to embrace the complexity of carbon nanocolloids. We point to the fundamental problems associated with their structure, photophysics, and photochemistry and highlight multiple directions of current and future research of this exciting class of nanomaterials.Fil: Ragazzon, Giulio. Università degli Studi di Trieste; ItaliaFil: Cadranel, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; ArgentinaFil: Ushakova, Elena V.. City University of Hong Kong; ChinaFil: Wang, Yichun. University of Michigan; Estados UnidosFil: Guldi, Dirk. Universitat Erlangen-Nuremberg; AlemaniaFil: Rogach, Andrey L.. City University of Hong Kong; ChinaFil: Kotov, Nicholas A.. University of Michigan; Estados UnidosFil: Prato, Maurizio. Università degli Studi di Trieste; Itali
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