Publications by authors named "Guillermina L Luque"

Li-S batteries are promising alternatives due to their proven increased gravimetric capacity compared to Li-ion batteries. However, their development is hindered by many technical issues, one of the most challenging being the dissolution and shuttle of polysulfide species, which causes irreversible loss of cathode material leading to rapid capacity fading. Among the possible strategies to mitigate this effect, the choice of suitable solvents is easy to implement and has large room for improvement.

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Anode-free metal batteries (AFMBs) are a new architecture of battery technology that relies solely on current collectors (CCs) at the anode side, eliminating the need for traditional metal anodes. This approach can pave the way for higher energy densities, lower manufacturing costs, and lower environmental footprints associated with metal batteries. This comprehensive review provides an in-depth exploration of AFMB technology, extending its scope beyond lithium and into a broader range of metals (sodium Na, potassium K, magnesium Mg, zinc Zn and aluminum Al).

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Capacity retention is a critical property to enhance in electrochemical storage systems applied to renewable energy. In lithium-sulfur (Li-S) batteries, the capacity fade resulting from the shuttle effect of polysulfides is a major obstacle to their practical application. Sepiolite, an eco-friendly earth-abundant clay with suitable surface chemistry for anchoring and retaining various molecules and structures, was studied as a cathode additive to mitigate the shuttle effect using experimental and theoretical approaches.

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Lithium-sulfur batteries are considered one of the possible next-generation energy-storage solutions, but to be commercially available many drawbacks have yet to be solved. One solution with great potentiality is the use of lithium sulfide as cathode material since it can be coupled to Li-free anodes, such as graphite, Si or Sn. Nevertheless, LiS, like sulfur, is electronically and ionically insulating, with a high activation potential for its initial oxidation step.

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Complex materials composed of two and three elements with high Li-ion storage capacity are investigated and tested as lithium-ion battery (LiB) negative electrodes. Namely, anodes containing tin, silicon, and graphite show very good performance because of the large gravimetric and volumetric capacity of silicon and structural support provided by tin and graphite. The performance of the composites during the first cycles was studied using ex situ magic angle spinning (MAS) Li Nuclear Magnetic Resonance (NMR), density functional theory (DFT) calculations, and electrochemical techniques.

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The performance of amperometric glucose biosensors based on the dispersion of glucose oxidase (GOx) and copper oxide within a classical carbon (graphite) paste composite is reported in this work. Copper oxide promotes an excellent electrocatalytic activity towards the oxidation and reduction of hydrogen peroxide, allowing a large decrease in the oxidation and reduction overpotentials, as well as an important enhancement of the corresponding currents. Therefore, it is possible to perform the glucose biosensing at low potentials where there is no interference even in large excess of ascorbic acid, uric acid or acetaminophen.

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The aim of this review is to summarize the most relevant contributions in the development of electrochemical (bio)sensors based on carbon nanotubes in the last years. Since the first application of carbon nanotubes in the preparation of an electrochemical sensor, an increasing number of publications involving carbon nanotubes-based sensors have been reported, demonstrating that the particular structure of carbon nanotubes and their unique properties make them a very attractive material for the design of electrochemical biosensors. The advantages of carbon nanotubes to promote different electron transfer reactions, in special those related to biomolecules; the different strategies for constructing carbon nanotubes-based electrochemical sensors, their analytical performance and future prospects are discussed in this article.

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In this work we report on the successful use of a composite prepared by dispersion of multi-wall carbon nanotubes (1-5 microm length, 20-50 nm diameter) and copper microparticles within mineral oil as detector for amino acids quantification in flow injection analysis and capillary electrophoresis. The resulting electrode displays a highly sensitive amperometric detection of amino acids, based on the copper dissolution facilitated by the strong activity of amino acids as ligands of Cu(II). The sensor makes possible the detection of amino acids, electroactive or not, at very low potentials (0.

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This work reports the advantages of using glassy carbon electrodes (GCEs) modified with multi-wall carbon nanotubes (CNT) dispersed in polyethylenimine (PEI) as detectors in flow injection and capillary electrophoresis. The presence of the dispersion of CNT in PEI at the electrode surface allows the highly sensitive and reproducible determination of hydrogen peroxide, different neurotransmitters (dopamine (D) and its metabolite dopac, epinephrine (E), norepinephrine (NE)), phenolic compounds (phenol (P), 3-chlorophenol (3-CP) and 2,3-dichlorophenol (2,3CP)) and herbicides (amitrol). Sensitivities enhancements of 150 and 140 folds compared to GCE were observed for hydrogen peroxide and amitrol, respectively.

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This work reports on the analytical performance of composites obtained by dispersing copper microparticles and multi-wall carbon nanotubes within a mineral oil binder (CNTPE-Cu) for the determination of amino acids and albumin. The strong complexing activity of amino acids towards copper makes possible an important improvement in the sensitivity for the determination of amino acids and albumin. This new electrode permits the highly sensitive amperometric detection of amino acids, even the non-electroactive ones, at very low potentials (0.

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