Purpose This paper aims to evaluate the inhibitive effect and adsorption behavior of 5-(ethylthio)-1H-tetrazole (EHT) and 5-(benzylthio)-1H-tetrazole (BHT) on copper in a sulfur-ethanol system. Design Methodology Approach Evaluation was carried out using electrochemical measurement and surface analysis techniques. Measurements of static friction coefficient by scanning electron microscopy and contact angle analysis were applied and finally confirmed the existence of the adsorbed film. The inhibitive mechanism of the two compounds was evaluated by means of quantitative calculation and molecular dynamics simulation. The friction coefficient of corrosion surface before and after adding corrosion inhibitor was determined through static friction coefficient measurements. Findings The electrochemical measurement indicated that the most effective concentration of two corrosion inhibitors was 70 mg L–1, while the inhibition efficiency of that was EHT > BHT. The friction coefficient data showed that the addition of corrosion inhibitor reduced the roughness of the corrosion surface. Adsorption behavior of two inhibitors followed the Langmuir’s adsorption isotherm and was attributed to mixed-type adsorption. The results of quantitative calculation and molecular dynamics simulation showed that tetrazole rings of the two inhibitors and its connected S atoms were adsorbed on Cu(111) surface in parallel. Originality Value The corrosion inhibition performance of two tetrazolium derivatives in a sulfur-ethanol system was studied by combining experiments with theory, which provided a theoretical basis for the future research.

Activated carbons (ACs) for supercapacitors were synthesized from Eucommia ulmoides Oliver (EUO) wood by H3PO4 with systemic activation processes. The target structure of ACs could be prepared by adjusting the technological parameters. As the H3PO4 concentration was 25%, the mass ratio of feedstocks to activator was 1:4, the activation time was 6 h, and the activation temperature was 400 °C, the obtained AC revealed a high specific surface area (2033.87 m2·g−1) and well-developed mesoporous (the rate of mesoporous was 96.4%) with the best economic feasibility. Besides, it possessed excellent electrochemical performance: the maximum specific capacitance reached up to 252 F·g−1, the charging and discharging period was 3098.2 s at 0.2 A·g−1, and the retention rate of specific capacitance reached 92.3% after 10,000 cycles. This low temperature and convenience technology provide a valuable reference for synthesizing the EUO-based ACs, making high-value utilization on the EUO branches, and owning a broad application prospect in supercapacitors.

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Purpose This paper aims to evaluate the inhibitive effect and adsorption behavior of the 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A) on copper in 3 per cent NaCl solution. Design/methodology/approach A thiazole Schiff bases were synthesized, named, 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A), which was fabricated respectively on copper surface by the molecular self-assembled. Evaluation was carried out by electrochemical measurement and surface analysis techniques. Measurement of static friction coefficient scanning electron microscopy and Contact angle analysis were applied, and it is finally confirmed the existence of the adsorbed film. The inhibitive mechanism of A was evaluated by means of quantitative calculation and molecular dynamics simulation. Findings The electrochemical measurement indicated that the self-assembled molecular film can effectively inhibit the corrosion of copper sheet, when the concentration was 15 mmol⋅L−1 and the assembly time was 6 h, the corrosion inhibition effect was the best, reaching as high as 97.5 per cent. Scanning electron microscopy results showed that the Schiff base compound forms a protective film on the surface of the copper, which effectively blocks the transfer of corrosion particles to the metal substrate, thereby inhibiting the occurrence of corrosion. Adsorption behavior of A followed the Langmuir’s adsorption isotherm and attributed to mixed-type adsorption. The results of Quantitative calculation and molecular dynamics simulation showed that A was adsorbed on Cu (111) surface in parallel. Research limitations/implications In this study, the corrosion inhibition properties of Schiff base film were investigated by combining theory with experiment. Theoretical calculation is helpful to guide the synthesis of efficient and environmentally friendly corrosion inhibitors. Practical implications The damage caused by metal corrosion is great. The self-assembled Schiff base membrane synthesized in this paper is simple and compact, and the corrosion inhibition efficiency of copper in 3 per cent NaCl solution is 97.5 per cent. Social implications Inhibition of metal corrosion can better save energy and reduce economic losses. Originality/value The synthesized Schiff base was prepared on the copper surface by the molecular self-assembled. The Schiff base membrane has a good corrosion inhibition effect on copper in 3 per cent NaCl solution, and the corrosion inhibition efficiency is up to 97.5 per cent.