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Pt-doped SnO2–Sb electrodes constitute promising candidates for the electrochemical abatement of refractory pollutants, but their efficacy to oxidize emerging pollutants remains uncertain. In this work, the electrochemical oxidation of diclofenac, pharmaceutical pollutant, on Pt-doped Ti/SnO2–Sb electrodes has been studied by cyclic voltammetry and galvanostatic treatment in neutral medium. In parallel, the capability of these anodes to generate hydroxyl radicals (OHs) has been analyzed by in-situ UV spectroelectrochemical measurements. For comparison purposes, the responses of Ti/SnO2–Sb and commercial Ti/Pt and BDD anodes were also evaluated. The voltammetric and electrolysis results show that the different Ti/SnO2–Sb anodes can effectively oxidize and mineralize diclofenac, so their electrochemical activity lies in between that of Ti/Pt and BDD. The incorporation of small amounts of Pt (3–13 at.%) into the SnO2–Sb coatings, despite hindering the OHs generation, enhances the kinetics and efficiency for diclofenac oxidation and mineralization. This better overall response is attributed to a synergy between diclofenac-Pt interaction and efficient OHs generation. Pt-doped Ti/SnO2–Sb electrodes are then presented as a cheaper potential alternative to BDD for treating pharmaceutics pollutants in waters. The authors thank the Spanish Ministerio de Economía y Competitividad (MINECO) and FEDER funds (grants MAT2016-76595-R and RYC-2017-23618) and Generalitat Valenciana (grant PROMETEO/2018/087) for financial support.

The production of titanium dioxide (TiO2) films on boron-doped diamond (BDD) surfaces to carry out heterojunctions has for some time become an attractive alternative to enhance the properties of both materials, in order to develop efficient photo-assisted processes to solve environmental problems, for example, the degradation of different industrial chemicals such as dyes, pharmaceuticals, pesticides, and metal ions, by this process tested in bench-scaled stirred are reviewed. The combination of these materials offers several advantages in water treatment, such as environmental compatibility, versatility, high efficiency, and safety, because they operate at room conditions. These key processes are carried out by means of photoelectrochemical treatments based on the degradation of organic compounds at photoanode from electrode reactions. Electrooxidation is the common electrochemical technique based on the destruction of organics at the anode via water discharge to promote free radicals (•OH), and the photocatalysis determined by the capacity of the catalyst to produce electron–hole pairs which generate free radicals that are able to undergo secondary reactions. Its concrete application was made possible through the discovery of water electrolysis by using TiO2. Now, the trend is the formation of films of TiO2 on the BDD to create highly efficient photoanodes through heterojunctions. In this chapter, we will present the most common synthesis methods used in the production of films, the physical and electrochemical characterization techniques that are used to study the new surfaces, some significant parameters on the decolorization, degradation, mineralization, and energy consumption are analyzed. As an important consideration, the decay kinetics of organic compounds and the evolution of intermediates are presented.

We report on the successful preparation of Fe-N codoped Titania powders, using TiO2Degussa P25, salt of Fe (II), and Urea. Modified Titania-based materials were characterized by SEM, EDS, BET, Raman, XRD diffraction and diffuse reflectance UV–vis spectroscopy measurements. The doping of TiO2 induced a shift in the absorption threshold toward the spectral range, obtaining catalysts with a greater photoactivity than the one of pure Degussa P25. The degradation of 200 mL of a solution with 50 mg L− 1acid blue BR dye in sulfate medium at pH 3.0 has been comparatively studied by electrochemical oxidation using a boron doped diamond anode (EO-BDD), Photocatalysis TiO2-Fe-N, and coupled material of EO-BDD/Photocatalysis TiO2-Fe-N. The solution was slowly degraded by EO-BDD (25%) and single Photocatalysis TiO2-Fe-N because of the low rate of dye degradation and its colored by-products with hydroxyl radicals generated at the BDD anode and catalyst surface from water oxidation (29%), whereas the solution was more rapidly degraded using coupled material of EO-BDD/Photocatalysis TiO2-Fe-N (82%), owing to the additional generation of hydroxyl radicals from the photocatalysis of TiO2-Fe-N and BDD anode. The authors thank the PRODEP Program (PRODEP-UGTO-PTC-472 and PRODEP 2015 UGTO-PTC-457) of UGTO under the Project 007/ 2015 (Convocatoria Institucional para Fortalecer la Excelencia Académica 2015), and the Project 778/2016 (Convocatoria Institucional de Apoyo a la Investigación Científica 2016-2017) is acknowledged. Authors thank Guanajuato University-CONACYT National Laboratory for SEM-EDX analysis. Financial support from the Spanish Ministry of Economy and Competitiveness in projects CTM2015-69845- R and CTQ2015-66078-R (MINECO/FEDER, UE) is gratefully acknowledged. C. J. Escudero thanks CONACYT-CONCYTEG for the postgraduate research grant (230713/383108) from Mexico.

In recent years, hard research has been aimed at developing more effective technologies for the treatment of water containing persistent organic contaminants. Among various technologies, the electrochemical advanced oxidation processes (EAOPs) recently have played a major role in water treatment science. These processes are based on the electrochemical promotion of strong oxidants such as free hydroxyl radicals (•OH). In the present chapter, we present an exhaustive evaluation of the treatment of various pollutants by some one key EAOPs, that is, the photoelectro-Fenton (PEF) process alone and in combination with other methods such as biological treatment and electrocoagulation. The fundamentals of these EAOPs are also given.

Plasma lipidome is now increasingly recognized as a potentially important marker of chronic diseases, but the exact extent of its contribution to the interindividual phenotypic variability in family studies is unknown. Here, we used the rich data from the ongoing San Antonio Family Heart Study (SAFHS) and developed a novel statistical approach to quantify the independent and additive value of the plasma lipidome in explaining metabolic syndrome (MS) variability in Mexican American families recruited in the SAFHS. Our analytical approach included two preprocessing steps: principal components analysis of the high-resolution plasma lipidomics data and construction of a subject-subject lipidomic similarity matrix. We then used the Sequential Oligogenic Linkage Analysis Routines software to model the complex family relationships, lipidomic similarities, and other important covariates in a variance components framework. Our results suggested that even after accounting for the shared genetic influences, indicators of lipemic status (total serum cholesterol, TGs, and HDL cholesterol), and obesity, the plasma lipidome independently explained 22% of variability in the homeostatic model of assessment-insulin resistance trait and 16% to 22% variability in glucose, insulin, and waist circumference. Our results demonstrate that plasma lipidomic studies can additively contribute to an understanding of the interindividual variability in MS.