Direct Z-scheme MgIn2S4/TiO2 heterojunction for enhanced photocathodic protection of metals under visible light

To improve the photocathodic protection performance of traditional TiO2 photoanodes for metals, constructing a Z-scheme heterojunction is one of the most promising and creative strategies. Herein, we fabricated a novel Z-scheme MgIn2S4 nanosheets/TiO2 nanotube nanocomposite through anodization and hydrothermal method. The optimized Z-scheme MgIn2S4/TiO2 nanocomposites exhibited stronger visible light absorption, higher separation efficiency of photoelectrons and photocathodic protection performances in comparison to pure TiO2. The theoretical analysis and experimental results show that the Z-scheme heterojunction and oxygen vacancies jointly improved the separation efficiency of photogenerated electron-hole pairs and visible light absorption capacity, thereby improving the photoelectric conversion performance of the MgIn2S4/TiO2 nanocomposites. Furthermore, the influence of the precursor solution concentration on the photocathodic protection performances of the composites was investigated. As a result, when the concentration of magnesium source in the precursor solution was 0.06 mmol, the prepared MgIn2S4/TiO2-0.06 displayed the best photocathodic protection performance. In addition, the hydroxyl radicals (•OH) generated in the electron spin resonance (ESR) experiment verified the Z-scheme heterojunction mechanism of the MgIn2S4/TiO2 composite, and also demonstrated the excellent redox performance of the composite. This work provides valuable reference for the construction of high-performance Z-scheme heterojunctions for photocathode protection of metals.

Advanced Coatings for the Corrosion Protection of Metals

The corrosion protection of metallic materials is of great importance in many fields, especially also when it comes to environmental issues. The book focuses on organic and inorganic coatings, metallic coatings and new methods for the deposition of protective thin layers. Coating techniques and methods for testing and assessing corrosion behavior are presented.

Theory and Applications of Green Corrosion Inhibitors

The book presents theoretical insights, characterization tools and mechanisms of green corrosion inhibitors and their industrial applications in areas such as reinforced concrete, coating, aircraft, oil and gas, acid pickling, water industry and the protection of metals and alloys used in electronic devices.

CATALYTIC SYN TIC SYNTHESIS OF PYRIDINES BASED ON THE CRO THESIS OF PYRIDINES BASED ON THE CROTON FRACTION

Background. The presence in the molecule of pyridine bases of nitrogen atoms having the properties of the bases determines the specificity of the products of this class and gives ample opportunities for their use in various industries. . The chemistry of pyridine bases is associated with such general theoretical issues as the electronic structure of the cycle, aromaticity, the effect of substituents on the reactivity of heterocycles in nucleophilic substitution reactions, and tautomerism. At the same time, systematic data on the reactions of alkylation with dihalo-alkanes, acylation under low-temperature poly-condensation, and complexation were not available to create a complete picture of the reactivity of pyridine bases. Materials and methods. The aim of the work is to develop cheap and convenient methods for the preparation of pyridine bases, to search for effective and selective process catalysts, and to determine the degree of anticorrosion protection of metals of the obtained products.

Review of Recent Developments in the Formulation of Graphene-Based Coatings for the Corrosion Protection of Metals and Alloys

Corrosion is a naturally occurring phenomenon and there is continuous interest in the development of new and more protective coatings or films that can be employed to prevent or minimise corrosion. In this review the corrosion protection afforded by two-dimensional graphene is described and discussed. Following a short introduction to corrosion, the application of graphene in the formulation of coatings and films is introduced. Initially, reduced graphene oxide (rGO) and metallic like graphene layers are reviewed, highlighting the issues with galvanic corrosion. Then the more successful graphene oxide (GO), functionalised GO and polymer grafted GO-modified coatings are introduced, where the functionalisation and grafting are tailored to optimise dispersion of graphene fillers. This is followed by rGO coupled with zinc rich coatings or conducting polymers, GO combined with sol-gels, layered double hydroxides or metal organic frameworks as protective coatings, where again the dispersion of the graphene sheets becomes important in the design of protective coatings. The role of graphene in the photocathodic protection of metals and alloys is briefly introduced, while graphene-like emerging materials, such as hexagonal boron nitride, h-BN, and graphitic carbon nitride, g-C3N4, are then highlighted.