Ana Teresa Brandão

Abstract Carbon materials are readily available and are essential in energy storage. One of the routes used to enhance their surface area and activity is the decoration of carbons with semiconductors, such as amorphous TiO2, for application in energy storage devices.

Abstract Lithium-sulfur batteries are a promising alternative to lithium-ion batteries as they can potentially offer significantly increased capacities and energy densities. The ever-increasing global battery market demonstrates that there will be an ongoing demand for cost effective battery electrode materials. Materials derived from waste products can simultaneously address two of the greatest challenges of today, i.e., waste management and the requirement to develop sustainable materials. In this study, we detail the carbonisation of gelatin from blue shark and chitin from prawns, both of which are currently considered as waste biproducts of the seafood industry. The chemical and physical properties of the resulting carbons are compared through a correlation of results from structural characterisation techniques, including electron imaging, X-ray diffraction, Raman spectroscopy and nitrogen gas adsorption. We investigated the application of the resulting carbons as sulfur-hosting electrode materials for use in lithium-sulfur batteries. Through comprehensive electrochemical characterisation, we demonstrate that value added porous carbons, derived from marine waste are promising electrode materials for lithium-sulfur batteries. Both samples demonstrated impressive capacity retention when galvanostatically cycled at a rate of C/5 for 500 cycles. This study highlights the importance of looking towards waste products as sustainable feeds for battery material production.

Abstract A plasmonic nanostructure was constructed as a biorecognition element coupled to an optical sensing platform in sandwich format, targeting the hazelnut Cor a 14 allergen-encoding gene. The analytical performance of the genosensor presented a linear dynamic range between 100 amol L-1 and 1 nmol L-1 , a limit of detection (LOD) < 19.9 amol L-1 , and a sensitivity of 13.4 +/- 0.6 m.. The genosensor was successfully hybridized with hazelnut PCR products, tested with model foods, and further validated by real-time PCR. It reached a LOD <0.001% (10 mg kg(-1) ) of hazelnut in wheat material (corresponding to 1.6 mg kg(-1) of protein) and a sensitivity of 17.2 +/- 0.5 m. for a linear range of 0.001%-1%. Herein, a new genosensing approach is proposed as a highly sensitive and specific alternative tool with potential application in monitoring hazelnut as an allergenic food, protecting the health of sensitized/allergic individuals.

Abstract Waste, in particular, biowaste, can be a valuable sourceof novelcarbon materials. Renewable carbon materials, such as biomass-derivedcarbons, have gained significant attention recently as potential electrodematerials for various electrochemical devices, including batteriesand supercapacitors. The importance of renewable carbon materialsas electrodes can be attributed to their sustainability, low cost,high purity, high surface area, and tailored properties. Fish wasterecovered from the fish processing industry can be used for energyapplications and prioritizing the circular economy principles. Herein,a method is proposed to prepare a high surface area biocarbon fromglycogen extracted from mussel cooking wastewater. The biocarbon materialswere characterized using a Brunauer-Emmett-Teller surfacearea analyzer to determine the specific surface area and pore sizeand by scanning electron microscopy coupled with energy-dispersiveX-ray analysis, Raman analysis, attenuated total reflectance Fouriertransform infrared spectroscopy, X-ray diffraction, X-ray photoelectronspectroscopy, and transmission electron microscopy. The electrochemicalcharacterization was performed using a three-electrode system, utilizinga choline chloride-based deep eutectic solvent (DES) as an eco-friendlyand sustainable electrolyte. Optimal time and temperature allowedthe preparation of glycogen-based carbon materials, with a specificsurface area of 1526 m(2) g(-1), a pore volumeof 0.38 cm(3) g(-1), and an associated specificcapacitance of 657 F g(-1) at a current density of1 A g(-1), at 30 degrees C. The optimal material wasscaled up to a two-electrode supercapacitor using a DES-based solid-stateelectrolyte (SSE@DES). This prototype delivered a maximum capacitanceof 703 F g(-1) at a 1 A g(-1) of currentdensity, showing 75% capacitance retention over 1000 cycles, deliveringthe highest energy density of 0.335 W h kg(-1) andpower density of 1341 W kg(-1). Marine waste can bea sustainable source for producing nanoporous carbon materials tobe incorporated as electrode materials in energy storage devices.

Abstract Many theoretical and experimental studies have been focused on the physicochemical properties of dense ionic fluids such as ionic liquids (ILs). However, less attention has been given to interfacial properties involving deep eutectic solvents (DES). The impact of the DES composition, hydrogen bond donor (HBD) structure, temperature, and electrode nature material on the DES-electrode vertical interactions remain vague. The lack of knowledge imposes significant constraints in proposing a suitable Electrical Double Layer model (EDL) to describe the DES at electrified interfaces. Measuring differential capacitance-potential curves is a strategy to assess the EDL structure and understand how ions interact with the electrode surface, which knowledge is fundamental to designing and optimizing electrochemical systems for various applications (e.g., energy storage devices). Accordingly, a set of choline chloride-based DESs was assessed containing distinct HBD at their eutectic composition (the poly-alcohol's 1,2-ethanediol, 1,2-propylene glycol, 1,3-propylene glycol, and the amide urea) against glassy carbon (GC), gold (Au), and the platinum (Pt) electrode at different temperatures. The differential capacitance-potential curves were found to vary significantly in shape in the three different electrode surfaces studied, ranging from camel shape (Au electrode), U-shape (GC), and asymmetric bell shape (polycrystalline Pt). The carboxylic malonic and oxalic acids were also assessed for a proper comparison to understand better the role of the HBD's functional group in shaping the electrode-electrolyte structure against the trend found with diol isomers. A suitable EDL model must inevitably accommodate interfacial properties assessed at the capacitive region, namely the influence of the surface chemistry, potential dependence, DES structure molecules, and temperature in shaping the electrified interfacial anatomy.