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Cu-modified TiO2 nanoparticles derived from MIL-125 were prepared by solvothermal method for the photocatalytic degradation of methylene blue under visible light illumination. For boosting the photocatalytic performance as well as the physicochemical properties of bare sample, 2 wt % Cu2+ ions were integrated into the nodes of the MIL-125 framework. The results showed that incorporation of 2 wt % Cu2+ ions into the MOF framework had significant effects on the crystallographic structure and morphological and optical properties of photocatalytic samples, as well as catalytic activity for the methylene blue degradation reaction. The high activity profile of Cu-modified TiO2 nanoparticles derived from MIL-125 might be attributed to the increased thermal stability, lower band gap energy, and smaller crystallite size of the sample. Activity tests were carried out at five varying MB initial concentrations and four different pH values. According to the findings, an increase in initial dye concentration resulted in a decrease in degradation efficiency. It was observed that increasing the pH value in the range of 3-11 initially led to higher degradation rates until pH 7, after which the degradation rate began to decline. [ABSTRACT FROM AUTHOR]

The polysulfide (PS) shuttle mechanism (PSM) is one of the biggest problems of lithium–sulfur (Li–S) batteries, resulting in fast capacity fading and low Coulombic efficiency. Due to electrostatic interactions, polar materials can adsorb the PS intermediates on their surfaces, decreasing the PSM effect. These polar materials should also have high electronic conductivity and surface area to be used in sulfur cathodes of Li–S batteries. In this respect, metal‐organic frameworks (MOF) and their derivatives gain significant attention. In this work, UiO‐66/graphene nanoplatelet (GNP)/sulfur composites are prepared with different UiO‐66/GNP ratios to investigate the effect of MOF amount on the electrochemical performance of Li–S batteries. MOF amount in the composite does not significantly influence performance for moderate S loadings. In contrast, Li–S cells with higher MOF‐loaded cathodes present superior performance at higher sulfur loadings and C rates. [ABSTRACT FROM AUTHOR]

A thermodynamic analysis was performed for the production of synthesis gas and hydrogen gas from steam reforming of propionic acid, one of the constituents of the bio-oil, using ASPEN Plus v8.8. The aim of the study was to perform a global analysis on steam reforming of propionic acid focusing on several parameters such as steam-to-propionic acid ratio, reaction temperature, addition of O 2 in the feed stream and presence of CaO as a CO 2 sorbent in the reaction environment. The results showed that higher amounts of steam/propionic acid ratio resulted in higher H 2 and CO 2 yields. It was also observed that high H 2 O/PA molar ratios led to reduced coke production as WGS reaction was favored with excess steam, causing CO in the reaction mixture to be consumed through the WGS reaction rather than the Boudouard reaction. Addition of O 2 in the reaction environment was observed to negatively affect yield of H 2. Yet, coke formation was deprived and increasing the O 2 amount in the feed stream decreased the energy required for the process. Furthermore, the presence of CaO enhanced H 2 yield and energy requirements of the process compared to conventional steam reforming process. 100 % yield of H 2 production with a heat generation of −83.4 MJ/kmol of PA and almost zero formation of CO 2 , CO, CH 4 and coke is achieved at 600 °C for sorption enhanced steam reforming of propionic acid. [Display omitted] • Maximum H 2 production is noted as 4.96 kmol/kmol of PA at 750 °C for H 2 O/PA = 4. • O 2 /PA molar ratio significantly affect the heat requirement & coke deposition. • Process enthalpy changes from 38.5 to −49.5 & −83.4 MJ/kmol with higher CaO. • 100% H 2 yield is achieved for CaO = 3 kmol/h at 600 and 700 °C. [ABSTRACT FROM AUTHOR]

Cu-modified TiO 2 nanoparticles derived from MIL-125 were prepared by solvothermal method for the photocatalytic degradation of methylene blue under visible light illumination. For boosting the photocatalytic performance as well as the physicochemical properties of bare sample, 2 wt % Cu 2+ ions were integrated into the nodes of the MIL-125 framework. The results showed that incorporation of 2 wt % Cu 2+ ions into the MOF framework had significant effects on the crystallographic structure and morphological and optical properties of photocatalytic samples, as well as catalytic activity for the methylene blue degradation reaction. The high activity profile of Cu-modified TiO 2 nanoparticles derived from MIL-125 might be attributed to the increased thermal stability, lower band gap energy, and smaller crystallite size of the sample. Activity tests were carried out at five varying MB initial concentrations and four different pH values. According to the findings, an increase in initial dye concentration resulted in a decrease in degradation efficiency. It was observed that increasing the pH value in the range of 3-11 initially led to higher degradation rates until pH 7, after which the degradation rate began to decline., (© TÜBİTAK.)