Publications by authors named "Flavia Tomarchio"

This work demonstrates the green production of a graphene ink for inkjet printing and its use as a hole transport layer (HTL) in an organic solar cell. Graphene as an HTL improves the selective hole extraction at the anode and prevents charge recombination at the electronic interface and metal diffusion into the photoactive layer. Graphite was exfoliated in water, concentrated by iterative centrifugation, and characterized by Raman.

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Multiple studies have reported the observation of electro-synaptic response in different metal/insulator/metal devices. However, most of them analyzed large (>1 µm ) devices that do not meet the integration density required by industry (10  devices/mm ). Some studies emploied a scanning tunneling microscope (STM) to explore nano-synaptic response in different materials, but in this setup there is a nanogap between the insulator and one of the metallic electrodes (i.

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Article Synopsis
  • The study examines a method for creating photocatalytic composites by using liquid-phase exfoliation of graphite with TiO nanoparticles in water and at room temperature, without any extra heating or surfactants.
  • These composites demonstrate significantly enhanced photocatalytic activity, degrading up to 40% more pollutants for a model dye and 70% more for nitrogen oxides compared to standard TiO nanoparticles.
  • The mechanisms of this enhanced performance are explored through ultrafast transient absorption spectroscopy, revealing that rapid electron transfer from TiO to graphite flakes reduces charge recombination and boosts the production of reactive species.
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We report vertically illuminated, resonant cavity enhanced, graphene-Si Schottky photodetectors (PDs) operating at 1550 nm. These exploit internal photoemission at the graphene-Si interface. To obtain spectral selectivity and enhance responsivity, the PDs are integrated with an optical cavity, resulting in multiple reflections at resonance, and enhanced absorption in graphene.

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Saturable absorbers (SA) operating at terahertz (THz) frequencies can open new frontiers in the development of passively mode-locked THz micro-sources. Here we report the fabrication of THz SAs by transfer coating and inkjet printing single and few-layer graphene films prepared by liquid phase exfoliation of graphite. Open-aperture z-scan measurements with a 3.

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We report the exfoliation of graphite in aqueous solutions under high shear rate [∼ 10 s] turbulent flow conditions, with a 100% exfoliation yield. The material is stabilized without centrifugation at concentrations up to 100 g/L using carboxymethylcellulose sodium salt to formulate conductive printable inks. The sheet resistance of blade coated films is below ∼2Ω/□.

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Graphene has unique physical and chemical properties, making it appealing for a number of applications in optoelectronics, sensing, photonics, composites, and smart coatings, just to cite a few. These require the development of production processes that are inexpensive and up-scalable. These criteria are met in liquid-phase exfoliation (LPE), a technique that can be enhanced when specific organic molecules are used.

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Neural-interfaces rely on the ability of electrodes to transduce stimuli into electrical patterns delivered to the brain. In addition to sensitivity to the stimuli, stability in the operating conditions and efficient charge transfer to neurons, the electrodes should not alter the physiological properties of the target tissue. Graphene is emerging as a promising material for neuro-interfacing applications, given its outstanding physico-chemical properties.

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