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One‐pot epoxy formulations, containing uncured resin, curing agent, and promoter, require the promoter to be insoluble in the resin at room temperature to prevent premature polymerization. Here, we introduce three novel reaction promoters synthesized by reacting amino propyl imidazole (API) and various diisocyanates such as HMDI, IPDI, or MDI. We evaluate the impact of these promoters on the physical properties, storage stability, and curing kinetics of the resulting epoxy formulations. The results of the kinetic study showed that the compositions containing each synthesized promoter acted as reaction promoters, as evidenced by the lower activation energy in the differential scanning calorimetry (DSC) experiment. The results of the mechanical properties showed that HMDI‐API promoter improved both tensile and flexural strength, while exhibiting high storage stability. The findings provide valuable insights for selecting suitable promoters for specific applications in one‐pot epoxy systems. [ABSTRACT FROM AUTHOR]

The glucose oxidation reaction (GOR) is a potential alternative to water oxidation because of its relatively low thermodynamic potential and the high availability of glucose. Herein, a FeCoO/N‐doped C electrode derived from metal–organic framework (MOF) materials is applied, which is synthesized in several steps through the controlled deposition of Fe–Co oxide nanocatalysts onto Co –N‐doped C nanofibers on a Ni foam substrate and demonstrate exceptional electrocatalytic activity for both the GOR and overall water splitting. Here, a bifunctional electrocatalyst derived from MOF, FeCoO/N‐doped C is reported, for glucose oxidation reaction (GOR) and hydrogen evolution reaction (HER). The MOF‐derived FeCoO/N‐doped C (+/‐) as a bifunctional electrocatalyst exhibits a cell voltage of 1.4 V for the GOR&HER, to reach a current density of 10 mA cm−2, which is 280 mV lower than that for the oxygen evolution reaction (OER)&HER (1.68 V). This study reveals that GOR is an energy‐efficient and affordable source of H2 and value‐added chemicals. [ABSTRACT FROM AUTHOR]

The tendency of epoxy resins to form three‐dimensional structures can make them brittle, which restricts their use in various applications even if they have great mechanical properties. Due to the expansion of epoxy resin application to electric automotives and aerospace as carbon fiber resistance plastics (CRFPs), it is desirable to synthesize epoxy resins that is more impact resistant. Herein, the synthesis of flexible epoxy resin FMER‐F and FMER‐J is reported. These epoxy resins were based on bisphenol F and J diglycidy ether. The dimeric fatty acid modified epoxy resins (FMERs) were synthesized by reacting acid anhydride modified epoxy resins (AMERs) with dimeric fatty acids. To obtain thermosetting epoxy polymers, the epoxy resin was mixed with a curing agent and an accelerator and, subsequently, it was cured at a high temperature. The mechanical properties of various epoxy polymers were analyzed to evaluate the change in the performance of the materials. The flexural strength of the composition with 10 parts per hundred resin (phr) of FMER‐F increased by 21%. The impact strength of the composition with 30 phr of FMER‐J increased by 27%. FMERs were found to be used as toughening agents in epoxy resins and composites because of their ability to enhance mechanical properties. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) emissions are an important environmental issue that causes greenhouse and climate change effects on the earth. Nowadays, CO2 has various conversion methods to be a potential carbon resource, such as photocatalytic, electrocatalytic, and photo-electrocatalytic. CO2 conversion into value-added products has many advantages, including facile control of the reaction rate by adjusting the applied voltage and minimal environmental pollution. The development of efficient electrocatalysts and improving their viability with appropriate reactor designs is essential for the commercialization of this environmentally friendly method. In addition, microbial electrosynthesis which utilizes an electroactive bio-film electrode as a catalyst can be considered as another option to reduce CO2. This review highlights the methods which can contribute to the increase in efficiency of carbon dioxide reduction (CO2R) processes through electrode structure with the introduction of various electrolytes such as ionic liquid, sulfate, and bicarbonate electrolytes, with the control of pH and with the control of the operating pressure and temperature of the electrolyzer. It also presents the research status, a fundamental understanding of carbon dioxide reduction reaction (CO2RR) mechanisms, the development of electrochemical CO2R technologies, and challenges and opportunities for future research. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) water splitting is an eco-friendly method for producing clean and sustainable hydrogen fuels. Compared with the fabrication of solar hydrogen using n-type metal oxide semiconductor photoanodes, that of solar hydrogen using p-type metal oxide semiconductor photocathodes has not been researched as thoroughly. Therefore, this study investigated the effect of drop casting time on the PEC performance of a prepared CuBi2O4 photocathode. XPS, HRTEM, UV-DRS, Raman spectroscopy, XRD, and SEM analyses were used to characterize the prepared CuBi2O4 photocathode. Owing to the high charge separation and transfer, the photocurrent density of the CuBi2O4 photocathode was ~0.6 mA cm−2 at 0.3 V vs. RHE. The nanoporous CuBi2O4 photocathode exhibited a high photocurrent density of up to 1.2 mA cm−2 at 0.3 V vs. RHE with H2O2 as a sacrificial agent. Mott–Schottky and impedance measurements were also performed on the CuBi2O4 photocathode to estimate its acceptor density and charge-transfer resistance. [ABSTRACT FROM AUTHOR]

As the demand for fiber-reinforced composite (FRC) has increased in various industries, composite materials have been manufactured in larger sizes and more complex shapes. Since the FRC has been manufactured in such larger and more complex shapes, wettability, one of the important factors in FRC manufacturing efficiency, has been the focus of many researchers. This paper explores various evaluation methods of the wettability between fiber and polymer matrix. Generally, work of adhesion, capillary, and permeability methods have been used to evaluate the wettability parameters between the fibers and the polymer matrix. These three parameters exhibit different scales of measurements such as surface energy, viscosity of the polymer, the fiber volume fraction, fiber orientation, and so on. Future research may include complementary studies between these evaluation methods. [ABSTRACT FROM AUTHOR]