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Screening of exfoliation conditions (dispersion solvent, prewetting solvent, microwave power, microwave irradiation time, MoS2–NMP ratio, and % yield); UV–vis analyses, optical and electronic microscopy analyses; thermogravimetric analysis of bulk and exfoliated MoS2, X-ray photoelectron spectroscopy analysis, electron transport measurements.

Hybrid systems based on superconducting planar resonators strongly coupled to magnetic molecules are promising candidates for future large-scale quantum processors. Superconducting microwave resonators allow the strong confinement of the electromagnetic fields mode volume, which is crucial for reaching a strong and coherent coupling with the spin qubits. However, achieving control over a few or single spins remains challenging. In this sense, two main issues need to be overcome. First, the cavity field effective volume needs to be further concentrated to maximize the addressability of a single spin in a controlled way. Second, as the microwave field is localized in a nanoscopic region, developing a method to deliver the magnetic sample with sufficient spatial accuracy is crucial. As a first approach, I. Gimeno et al. showed that reducing the width of a superconducting transmission line locally leads to an enhancement of the microwave magnetic field and, therefore, of the achieved coupling. Utilizing dip pen nanolithography, they can place nanodeposits in a controlled way, reducing the number of coupled spins by several orders of magnitude. However, new approaches must be developed to achieve strong coupling to a single spin. We propose to downscale and reach the single-spin sensitivity limit by replacing the constriction of the superconducting resonator with a carbon nanotube (CNT). This approach presents two significant advantages: first, it concentrates further the microwave magnetic volume, increasing the coupling rate to a single spin; second, as CNT can be directly functionalized with molecular species, it allows addressing a single magnetic molecule in a localized position. Preliminary results of a hybrid superconducting/CNT resonator are presented, where the controlled positioning of the carbon nanotube on the nanometer scale has been achieved by dielectrophoresis. Moreover, optimized superconducting lumped element resonators (LERs) have been developed and co

[EN] Magnetism and the existence of magnetic order in a material is determined by its dimensionality. In this regard, the recent emergence of magnetic layered van der Waals (vdW) materials provides a wide playground to explore the exotic magnetism arising in the two-dimensional (2D) limit. The magnetism of 2D flakes, especially antiferromagnetic ones, however, cannot be easily probed by conventional magnetometry techniques, being often replaced by indirect methods like Raman spectroscopy. Here, we make use of an alternative approach to provide direct magnetic evidence of few-layer vdW materials, including antiferromagnets. We take advantage of a surfactant-free, liquid-phase exfoliation (LPE) method to obtain thousands of few-layer FePS3 flakes that can be quenched in a solvent and measured in a conventional SQUID magnetometer. We show a direct magnetic evidence of the antiferromagnetic transition in FePS3 few-layer flakes, concomitant with a clear reduction of the Néel temperature with the flake thickness, in contrast with previous Raman reports. The quality of the LPE FePS3 flakes allows the study of electron transport down to cryogenic temperatures. The significant through-flake conductance is sensitive to the antiferromagnetic order transition. Besides, an additional rich spectra of electron transport excitations, including secondary magnetic transitions and potentially magnon-phonon hybrid states, appear at low temperatures. Finally, we show that the LPE is additionally a good starting point for the mass covalent functionalization of 2D magnetic materials with functional molecules. This technique is extensible to any vdW magnetic family.

The most widespread method for the synthesis of 2D–2D heterostructures is the direct growth of one material on top of the other. Alternatively, flakes of different materials can be manually stacked on top of each other. Both methods typically involve stacking 2D layers through van der Waals forces—such that these materials are often referred to as van der Waals heterostructures—and are stacked one crystal or one device at a time. Here we describe the covalent grafting of 2H-MoS2 flakes onto graphene monolayers embedded in field-effect transistors. A bifunctional molecule featuring a maleimide and a diazonium functional group was used, known to connect to sulfide- and carbon-based materials, respectively. MoS2 flakes were exfoliated, functionalized by reaction with the maleimide moieties and then anchored to graphene by the diazonium groups. This approach enabled the simultaneous functionalization of several devices. The electronic properties of the resulting heterostructure are shown to be dominated by the MoS2–graphene interface.

Grado en Lenguas Modernas y sus Literaturas

The invention relates to: polypeptides with polysaccharide monooxygenase activity; a host cell expressing said polypeptides, preferably a Myceliophthora thermophila cell that recombinantly expresses at least one of said polypeptides; an enzymatic composition comprising at least one of said polypeptides, preferably together with other cellulolytic enzymes; the use of said host cell, of at least one of the polypeptides with polysaccharide monooxygenase activity or of the enzymatic composition for the degradation of cellulosic biomass; and a method for producing bioproducts, preferably bioethanol, comprising the use of said host cell, of at least one of the polypeptides of the invention or of the enzymatic composition of the invention.

Thermochemical pretreatment and enzymatic hydrolysis are the areas contributing most to the operational costs of second generation ethanol in lignocellulosic biorefineries. The improvement of lignocellulosic enzyme cocktails has been significant in the recent years. Although the needs for the reduction of the energy intensity and chemical consumption in the pretreatment step are well known, the reduction of the severity of the process strongly affects the enzymatic hydrolysis yield. To explore the formulation requirements of the well known cellulolytic cocktail from Myceliophthora thermophila on mild pretreated raw materials, this cocktail was tested on steam exploded corn stover without acid impregnation. The low hemicellulose yield and significant accumulation of xylobiose compared with the standard pretreated material obtained with dilute acid impregnation evidenced a clear limitation in the conversion of xylan to xylose. In order to complement the beta-xylosidase limitation, a selection of enzymes was expressed and tested in this fungus. A controlled expression of xylosidases from Aspergillus nidulans, Aspergillus fumigatus, and Fusarium oxysporum allowed recovering hemicellulose yields reached with standard acid treated material. The results underline the need of parallel development of the pretreatment process with the optimization of the formulation of the enzymatic cocktails.