Cost Effective Synthesis of Graphene Nanomaterials for Non-Enzymatic Electrochemical Sensors for Glucose: A Comprehensive Review

The high conductivity of graphene material (or its derivatives) and its very large surface area enhance the direct electron transfer, improving non-enzymatic electrochemical sensors sensitivity and its other characteristics. The offered large pores facilitate analyte transport enabling glucose detection even at very low concentration values. In the current review paper we classified the enzymeless graphene-based glucose electrocatalysts’ synthesis methods that have been followed into the last few years into four main categories: (i) direct growth of graphene (or oxides) on metallic substrates, (ii) in-situ growth of metallic nanoparticles into graphene (or oxides) matrix, (iii) laser-induced graphene electrodes and (iv) polymer functionalized graphene (or oxides) electrodes. The increment of the specific surface area and the high degree reduction of the electrode internal resistance were recognized as their common targets. Analyzing glucose electrooxidation mechanism over Cu-Co-and Ni-(oxide)/graphene (or derivative) electrocatalysts, we deduced that glucose electrochemical sensing properties, such as sensitivity, detection limit and linear detection limit, totally depend on the route of the mass and charge transport between metal(II)/metal(III); and so both (specific area and internal resistance) should have the optimum values. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Asst. Prof. Brouzgou, A., thankfully acknowledges the Research, Innovation and Excellence Structure (DEKA) of the University of Thessaly for the funding of the research program entitled: ‘Electrochemical (bio)sensors: synthesis of novel carbon monolayer-based nanoelectrodes for biomolecules detection’ and Ms Balkourani, G. (PhD student) thankfully acknowledges the Hellenic Foundation for Research and Innovation (HFRI), the PhD Fellowship grant. 25, 6816

Thermochemical conversion of biomass to second generation biofuels through integrated process design--A review

The need for clean and environmental friendly fuels is leading the world to the production of biofuels and replacing conventional fuels by them. Second generation biofuels derived from lignocellulosic feedstocks tackle the drawbacks posed by the so-called first generation ones regarding feedstock availability and competition with the food industries. Thermochemical conversion of biomass to biofuels is a promising alternative route relying on well-established technologies including gasification and the Fischer-Tropsch synthesis. The conjunction of these processes creates a pathway through which the production of biofuels is sustainable. However, the multiple interactions between the processing steps greatly increase the difficulty in the accurate design of such processes. Detailed process modelling and optimization studies combined with process integration methods are necessary to demonstrate an effective way for the exploitation of these interactions. The aim of this work is to present and analyze the thermochemical conversion of biomass to second generation liquid biofuels as well as to indicate the emerging challenges and opportunities of the application of process integration on such processes towards innovative and sustainable solutions concerning climate concerns and energy security.Biomass Second generation biofuels Process integration Process design Modelling Optimization

Cost Effective Synthesis of Graphene Nanomaterials for Non-Enzymatic Electrochemical Sensors for Glucose: A Comprehensive Review

The high conductivity of graphene material (or its derivatives) and its very large surface area enhance the direct electron transfer, improving non-enzymatic electrochemical sensors sensitivity and its other characteristics. The offered large pores facilitate analyte transport enabling glucose detection even at very low concentration values. In the current review paper we classified the enzymeless graphene-based glucose electrocatalysts’ synthesis methods that have been followed into the last few years into four main categories: (i) direct growth of graphene (or oxides) on metallic substrates, (ii) in-situ growth of metallic nanoparticles into graphene (or oxides) matrix, (iii) laser-induced graphene electrodes and (iv) polymer functionalized graphene (or oxides) electrodes. The increment of the specific surface area and the high degree reduction of the electrode internal resistance were recognized as their common targets. Analyzing glucose electrooxidation mechanism over Cu-Co-and Ni-(oxide)/graphene (or derivative) electrocatalysts, we deduced that glucose electrochemical sensing properties, such as sensitivity, detection limit and linear detection limit, totally depend on the route of the mass and charge transport between metal(II)/metal(III); and so both (specific area and internal resistance) should have the optimum values. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Novel energy crops for Mediterranean contaminated lands: Valorization of Dittrichia viscosa and Silybum marianum biomass by pyrolysis

9 páginas.-- 4 figuras.-- 3 tablas.-- 5 referencias.-- Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.chemosphere.2017.08.063Establishing energy crops could be a cost-efficient alternative towards the valorization of the plant biomass produced in contaminated lands, where they would not compete with food production for land use. Dittrichia viscosa and Silybum marianum are two native Mediterranean species recently identified as potential energy crops for degraded lands. Here, we present the first characterization of the decomposition of the biomass of these species during thermo-chemical conversion (pyrolysis). Using a greenhouse study we evaluated whether the quality of D. viscosa and S. marianum biomass for energy production through pyrolysis could be substantially influenced by the presence of high concentrations of soluble trace element concentrations in the growing substrate. For each species, biomass produced in two different soil types (with contrasted trace element concentrations and pH) had similar elemental composition. Behavior during thermal decomposition, activation energies and concentrations of pyrolysis gases were also similar between both types of soils. Average activation energy values were 295 and 300 kJ mol−1 (for a conversion value of α = 0.5) for S. marianum and D. viscosa, respectively. Results suggest that there were no major effects of soil growing conditions on the properties of the biomass as raw material for pyrolysis, and confirm the interest of these species as energy crops for Mediterranean contaminated lands.This work was supported by the Iberdrola Foundation (Young Researchers Program) and the Spanish Ministry of Economy and Competitiveness (AGL2014-55717-R project and CTQ2013-46804-C2-1-R projects). We are grateful to Patricia Puente and Cristina García for their help at different stages of the study. MTD was supported by a Juan de la Cierva Postdoctoral fellowship from the Spanish Ministry of Economy and Competitiveness, and a postdoctoral fellowship from University of Seville (V Plan Propio).Peer reviewe