Alexi Cosmos Arango

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Since the mixing ratio of the anions in the solution from which the crystals were grown was revealed to be almost identical to the stoichiometry determined by EPMA of the obtained crystal, the mixing ratio of the anions in the solution was adopted in the chemical formula of the crystal. The results of EPMA of k-(BETS) 2 Fe x Ga 1±x Br 1.0 Cl 3.0 are: for x(More)
We demonstrate a bilayer photovoltaic device consisting of a heterojunction between colloidal cadmium selenide (CdSe) quantum dots (QDs) and a wide band gap organic hole-transporting thin film of N,N'-diphenyl-N,N'-bis(3-methylphenyl)[1,1'-biphenyl]-4,4'-diamine (TPD) molecules. The active light-absorbing film of QDs is nondestructively printed onto TPD(More)
Citation Osedach, Tim P. et al. " Lateral heterojunction photodetector consisting of molecular organic and colloidal quantum dot thin films. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available.(More)
Solution-processable colloidal quantum-dot systems exhibit many of the special optical and electronic properties associated with epitaxially grown, quantum confined systems. Their tunable band gap and higher absorption relative to the bulk make quantum dots particularly attractive as photo-generation materials. At the same time, colloidal quantum dots offer(More)
This thesis presents the first colloidal quantum dot light emitting devices (QD-LEDs) with metal oxide charge transport layers. Colloidally synthesized quantum dots (QDs) have shown promise as the active material in optoelectronic devices because of their tunable, narrow band emission. To date, the most efficient QD-LEDs involve a mono-layer of closely(More)
We demonstrate a heterojunction photodetector consisting of a metal-oxide charge transport layer and a colloidal quantum-dot (QD) charge-generation layer. To make the device, a metal-oxide semiconductor, SnO 2 , is sputter-deposited over an array of interdigitated gold electrodes. A thin film of PbS QDs is then spin-coated over the structure (see Figure(More)
BACKGROUND The first cases of multiple sclerosis (MS) in Panama were notified in the 1980s and it was considered a low-risk region for this disease. Between 2000 and 2005, a prevalence study was conducted to characterize MS in Panama. METHODS An instrument was developed to gather information from clinical files and interviews with previous informed(More)
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