High efficiency blue organic light-emitting diodes with below-bandgap electroluminescence

Blue organic light-emitting diodes require high triplet interlayer materials, which induce large energetic barriers at the interfaces resulting in high device voltages and reduced efficiencies. Here, we alleviate this issue by designing a low triplet energy hole transporting interlayer with high mobility, combined with an interface exciplex that confines excitons at the emissive layer/electron transporting material interface. As a result, blue thermally activated delay fluorescent organic light emitting diodes with a below-bandgap turn-on voltage of 2.5 V and an external quantum efficiency of 41.2% were successfully fabricated. These devices also showed suppressed efficiency roll-off maintaining an EQE of 34.8% at 1000 cd m-2. Our approach paves the way for further progress through exploring alternative device engineering approaches instead of only focusing on the demanding synthesis of organic compounds with complex structures

Zinc Phthalocyanine−Graphene Hybrid Material for Energy Conversion: Synthesis, Characterization, Photophysics and Photoelectrochemical Cell Preparation

Graphene exfoliation upon tip sonication in o-­‐DCB was accomplished. Then, covalent grafting of (2-­‐ aminoethoxy)(tri-­‐tert-­‐butyl) zinc phthalocyanine (ZnPc), to exfoliated graphene sheets was achieved. The newly formed ZnPc-­‐graphene hybrid material was found soluble in common organic solvents without any precipitation for several weeks. Application of diverse spectroscopic techniques verified the successful formation of ZnPc-­‐graphene hybrid materi-­‐ al, while thermogravimetric analysis revealed the amount of ZnPc loading onto graphene. Microscopy analysis based on AFM and TEM was applied to probe the morphological characteristics and to investigate the exfoliation of graphene sheets. Efficient fluorescence quenching of ZnPc in the ZnPc-­‐graphene hybrid material suggested that photoinduced events occur from the photoexcited ZnPc to exfoliated graphene. The dynamics of the photoinduced electron transfer was evaluated by femtosecond transient absorption spectroscopy, thus, revealing the formation of transient species such as ZnPc+ yielding the charge-­‐separated state ZnPc•+–graphene•–. Finally, the ZnPc-­‐graphene hybrid material was integrated into a photoactive electrode of an optical transparent electrode (OTE) cast with nanostructured SnO2 films (OTE/SnO2), which exhibited sta le and reproducible photocurrent responses and the incident photon-­‐to-­‐current conversion efficien-­‐ cy was determine

Tunable reactivity of triphosgene-triethylamine: A study on the synthesis of pyrrole-based tricyclics

The synthesis of novel pyrrolo[1,2-c][1,3]benzodiazepine and pyrrolo[3,2-c]- [1]benzazepine ring systems from (2-aminophenyl)(1H-pyrrol-2-yl)methanone and 2-[(1H-pyrrol-2-yl)methyl]aniline is presented, utilizing triphosgene as carbonylation-cyclization reagent for the formation of the 7-membered heterocycle. A study of the reaction shows that small changes in the reaction conditions affect dramatically the course of the reaction. Acidity as well as aqueous workup play significant roles in the reaction outcome, directing product formation and revealing important aspects of triphosgene mediated cyclizations. © 2020 Elsevier Lt

Vacancy migration in hexagonal boron nitride

International audienc

Azafullerenes encapsulated within single-walled carbon nanotubes.

Methods of insertion of azafullerenes in single-walled carbon nanotubes (SWNTs) at different temperatures were investigated, while the effects of the conditions applied on the structure of azafullerene-based peapods, namely, C59N@SWNTs, were explored. Morphological characteristics of C59N@SWNTs were assessed and evaluated by means of high-resolution transmission electron microscopy (HR-TEM). Pathways and chemical reactions that occur upon encapsulation of C59N within SWNTs were evaluated. Monomeric azafullerenyl radical C59N. as inserted into SWNTs at high temperature, from purified (C59N)2 in the gas phase, can undergo a variety of different transformations forming dimers, oligomers or existing in its monomeric form inside SWNTs due to the stabilization effect by nanotube side walls. However, under milder conditions, that is, at lower temperature, bisazafullerene (C59N)2 can be inserted into SWNTs in its pristine dimeric form

Cyclooxygenase-2 Expression in Non-Small Cell Lung Cancer Correlates With Hypertrophic Osteoarthropathy.

Hypertrophic osteoarthrpathy (HO) is a rare paraneoplasic syndrome associated with non-small cell lung cancer (NSCLC). The pathophysiology of HO is unknown but was recently related to enhanced levels of urine prostaglandin E2 (PGE2). Here, we report the case of a patient that presented HO in association with a resectable left upper lobe NSCLC. Following surgery and adjuvant chemotherapy, HO resolved and did not recur with development of a brain metastasis 1 year later. Interestingly, tumor cyclooxygenase-2, an enzyme responsible the synthesis of PGE2, was expressed in the primary tumor but not in the resected metastasis

Method

The invention provides mitochondria-targeted chemiluminescent agents and their use in methods of photodynamic therapy (PDT). In particular, the invention provides compounds of general formula (1), and their pharmaceutically acceptable salts: (1) in which A represents a chemiluminescent moiety; each L, which may be the same or different, is either a direct bond or a linker; each B, which m ay be the same or different, represents a mitotropic moiety; n is an integer from 1 to 3, preferably 1; and x is an integer from 1 to 3, preferably 1. Such compounds find particular use in the treatment of deeply-sited tumours, e.g. glioblastoma multiforme (GBM), when used in combination with a photosensitizer or photosensitizer precursorPeer reviewedOslo Universitetssykehus HF, Consejo Superior de Investigaciones Científicas (España), Universitat Politècnica de ValènciaA1 Solicitud de patente con informe sobre el estado de la técnic

Method

The invention provides mitochondria-targeted chemiluminescent agents and their use in methods of photodynamic therapy (PDT). In particular, the invention provides compounds of general formula (1), and their pharmaceutically acceptable salts: (1) in which A represents a chemiluminescent moiety; each L, which may be the same or different, is either a direct bond or a linker; each B, which m ay be the same or different, represents a mitotropic moiety; n is an integer from 1 to 3, preferably 1; and x is an integer from 1 to 3, preferably 1. Such compounds find particular use in the treatment of deeply-sited tumours, e.g. glioblastoma multiforme (GBM), when used in combination with a photosensitizer or photosensitizer precursorPeer reviewedOslo Universitetssykehus HF, Consejo Superior de Investigaciones Científicas (España), Universitat Politècnica de ValènciaA1 Solicitud de patente con informe sobre el estado de la técnic

Method

The invention provides mitochondria-targeted chemiluminescent agents and their use in methods of photodynamic therapy (PDT). In particular, the invention provides compounds of general formula (1), and their pharmaceutically acceptable salts: (1) in which A represents a chemiluminescent moiety; each L, which may be the same or different, is either a direct bond or a linker; each B, which m ay be the same or different, represents a mitotropic moiety; n is an integer from 1 to 3, preferably 1; and x is an integer from 1 to 3, preferably 1. Such compounds find particular use in the treatment of deeply-sited tumours, e.g. glioblastoma multiforme (GBM), when used in combination with a photosensitizer or photosensitizer precursorPeer reviewedOslo Universitetssykehus HF, Consejo Superior de Investigaciones Científicas (España), Universitat Politècnica de ValènciaA1 Solicitud de patente con informe sobre el estado de la técnic