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Catalytic oxidative desulfurization (ODS) using titanium silicate catalysts has emerged as an efficient technique for the complete removal of organosulfur compounds from automotive fuels. However, the precise control of highly accessible and stable-framework Ti active sites remains highly challenging. Here we reveal for the first time by using density functional theory calculations that framework hexa-coordinated Ti (TiO6) species of mesoporous titanium silicates are the most active sites for ODS and lead to a lower-energy pathway of ODS. A novel method to achieve highly accessible and homogeneously distributed framework TiO6 active single sites at the mesoporous surface has been developed. Such surface framework TiO6 species exhibit an exceptional ODS performance. A removal of 920 ppm of benzothiophene is achieved at 60°C in 60 min, which is 1.67 times that of the best catalyst reported so far. For bulky molecules such as 4,6-dimethyldibenzothiophene (DMDBT), it takes only 3 min to remove 500 ppm of DMDBT at 60°C with our catalyst, which is five times faster than that with the current best catalyst. Such a catalyst can be easily upscaled and could be used for concrete industrial application in the ODS of bulky organosulfur compounds with minimized energy consumption and high reaction efficiency. [ABSTRACT FROM AUTHOR]

The article discusses the limitations of lithium-ion batteries (LIBs) and the growing interest in aqueous batteries as a sustainable alternative. Aqueous batteries are attractive due to their low cost and high safety, but their energy density and cycling performance need improvement for industrial applications. The optimization of electrode materials and electrolytes is a focus of research in aqueous batteries. The article also explores the voltage matching principle, different types of electrochemical reactions, and measures to enhance the energy density of aqueous batteries. The nature of the electrolyte and practical considerations for aqueous batteries are also discussed. While current aqueous batteries have met the demand for energy storage systems to some extent, further development in electrode and electrolyte engineering is expected to make next-generation aqueous batteries commercially viable. [Extracted from the article]

The article discusses the Fischer-Tropsch (FT) synthesis, a process used to convert synthesis gas into hydrocarbons. The precise mechanistic steps of this reaction are still debated, but recent research has reported periodic rate-and-selectivity oscillations in the FT reaction over a Co/Ce-oxide powder catalyst. These oscillations were accompanied by temperature variations and were attributed to Arrhenius factors associated with C-O bond breaking. The findings suggest the possibility of generating self-sustained oscillatory behavior in the FT reaction, which could lead to enhanced reaction rates and selectivity. This research has the potential to inspire further investigation into kinetic instabilities in complex catalytic reactions and the development of dynamic catalyst design strategies. [Extracted from the article]

Like nanomaterials, bacteria have been unknowingly used for centuries. They hold significant economic potential for fuel and medicinal compound production. Their full exploitation, however, is impeded by low biological activity and stability in industrial reactors. Though cellular encapsulation addresses these limitations, cell survival is usually compromised due to shell-to-cell contacts and low permeability. Here, we report ordered packing of silica nanocolloids with organized, uniform and tunable nanoporosities for single cyanobacterium nanoencapsulation using protamine as an electrostatic template. A space between the capsule shell and the cell is created by controlled internalization of protamine, resulting in a highly ordered porous shell-void-cell structure formation. These unique yolk-shell nanostructures provide long-term cell viability with superior photosynthetic activities and resistance in harsh environments. In addition, engineering the colloidal packing allows tunable shell-pore diameter for size-dependent permeability and introduction of new functionalities for specific molecular recognition. Our strategy could significantly enhance the activity and stability of cyanobacteria for various nanobiotechnological applications. [ABSTRACT FROM AUTHOR]

Active crystal facets can generate special properties for various applications. Herein, we report a (001) faceted nanosheet-constructed hierarchically porous TiO2/rGO hybrid architecture with unprecedented and highly stable lithium storage performance. Density functional theory calculations show that the (001) faceted TiO2 nanosheets enable enhanced reaction kinetics by reinforcing their contact with the electrolyte and shortening the path length of Li+ diffusion and insertion-extraction. The reduced graphene oxide (rGO) nanosheets in this TiO2/rGO hybrid largely improve charge transport, while the porous hierarchy at different length scales favors continuous electrolyte permeation and accommodates volume change. This hierarchically porous TiO2/rGO hybrid anode material demonstrates an excellent reversible capacity of 250 mAh g–1 at 1 C (1 C = 335 mA g–1) at a voltage window of 1.0–3.0 V. Even after 1000 cycles at 5 C and 500 cycles at 10 C, the anode retains exceptional and stable capacities of 176 and 160 mAh g–1, respectively. Moreover, the formed Li2Ti2O4 nanodots facilitate reversed Li+ insertion-extraction during the cycling process. The above results indicate the best performance of TiO2-based materials as anodes for lithium-ion batteries reported in the literature. [ABSTRACT FROM AUTHOR]

Catalytic oxidative desulfurization (ODS) using titanium silicate catalysts has emerged as an efficient technique for the complete removal of organosulfur compounds from automotive fuels. However, the precise control of highly accessible and stable-framework Ti active sites remains highly challenging. Here we reveal for the first time by using density functional theory calculations that framework hexa-coordinated Ti (TiO 6 ) species of mesoporous titanium silicates are the most active sites for ODS and lead to a lower-energy pathway of ODS. A novel method to achieve highly accessible and homogeneously distributed framework TiO 6 active single sites at the mesoporous surface has been developed. Such surface framework TiO 6 species exhibit an exceptional ODS performance. A removal of 920 ppm of benzothiophene is achieved at 60°C in 60 min, which is 1.67 times that of the best catalyst reported so far. For bulky molecules such as 4,6-dimethyldibenzothiophene (DMDBT), it takes only 3 min to remove 500 ppm of DMDBT at 60°C with our catalyst, which is five times faster than that with the current best catalyst. Such a catalyst can be easily upscaled and could be used for concrete industrial application in the ODS of bulky organosulfur compounds with minimized energy consumption and high reaction efficiency., (© The Author(s) 2024. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

Active crystal facets can generate special properties for various applications. Herein, we report a (001) faceted nanosheet-constructed hierarchically porous TiO 2 /rGO hybrid architecture with unprecedented and highly stable lithium storage performance. Density functional theory calculations show that the (001) faceted TiO 2 nanosheets enable enhanced reaction kinetics by reinforcing their contact with the electrolyte and shortening the path length of Li + diffusion and insertion-extraction. The reduced graphene oxide (rGO) nanosheets in this TiO 2 /rGO hybrid largely improve charge transport, while the porous hierarchy at different length scales favors continuous electrolyte permeation and accommodates volume change. This hierarchically porous TiO 2 /rGO hybrid anode material demonstrates an excellent reversible capacity of 250 mAh g -1 at 1 C (1 C = 335 mA g -1 ) at a voltage window of 1.0-3.0 V. Even after 1000 cycles at 5 C and 500 cycles at 10 C, the anode retains exceptional and stable capacities of 176 and 160 mAh g -1 , respectively. Moreover, the formed Li 2 Ti 2 O 4 nanodots facilitate reversed Li + insertion-extraction during the cycling process. The above results indicate the best performance of TiO 2 -based materials as anodes for lithium-ion batteries reported in the literature., (© The Author(s) 2020. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)