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Selective synthesis of large diameter single-walled carbon nanotubes (SWCNTs) is desired for a variety of applications, but most catalysts can only synthesize SWCNTs with a diameter less than 2 nm. Here, a low cost and green catalyst (Co/RH-SiO 2) was prepared by using rice husk-derived SiO 2 as the catalyst support, which selectively synthesized large SWCNTs (d t > 2 nm) with a percentage of 70.7 % among all tubes grown at the high growth temperature of 950 ℃. The carbon yield produced on this catalyst containing 1 wt% Co was 4.49 wt%. In contrast, commercial SiO 2 supported Co catalyst (Co/Cab-SiO 2) synthesized smaller SWCNTs with a broad diameter distribution under the same growth condition. The detailed characterizations of catalysts showed that Co/RH-SiO 2 catalyst is unique with the abundant small mesopores (2–4 nm) and reducible Co hydrosilicate and surface Co silicates highly dispersed in the pore structures. The reduction of Co hydrosilicate and surface Co silicates facilitates the formation of large Co clusters, which are stabilized by irreducible Co silicates and small mesopores, leading to the growth of large-diameter SWCNTs. Results in this study provide useful insights to develop low cost and green catalysts from biomass waste for the selective growth of SWCNTs. [Display omitted] ● Rice husk-derived SiO 2 was used as the support to prepare Co/RH-SiO 2 catalyst. ● Large-diameter single-walled carbon nanotubes (d>2 nm) were synthesized on Co/RH-SiO 2. ● Co/RH-SiO 2 catalyst was unique with abundant small mesopores (2–4 nm). ● Co species were highly dispersed in the mesopore structures of Co/RH-SiO 2. [ABSTRACT FROM AUTHOR]

The scalable hydrogenation of vinylic, allylic, and homoallylic sulfones is investigated with the conversion of the E-isomers being faster than the one of Z-isomers while delivering opposite enantiomers. [ABSTRACT FROM AUTHOR]

[Display omitted] • The oxidation mechanism and the influencing factors of EOPs are systematically presented. • The advantages and limitations of commonly used anode materials and their evaluation criteria and systems are reviewed. • The key challenges of EOPs in theoretical research and practical application are analyzed. • Perspective and suggestions for the future development of EOPs are proposed. Compared with conventional wastewater treatment processes, electrochemical oxidation processes (EOPs) can remove hazardous substances from wastewater more efficiently and without pollution. With the rapid development of green power technology, there are more development prospects for EOPs in wastewater treatment. In recent years, research related to EOPs in the field of wastewater treatment has flourished, numerous researchers have reviewed the last advances. However, the key challenges and future directions of EOPs in the context of carbon neutrality are still under-analyzed. In this review, we first summarize the oxidation mechanism and various control factors of EOPs. Then, we discuss the current development status of current and emerging electrode materials, and summarize their commonly used evaluation criteria and systems. Finally, based on the above review, we analyze the key challenges faced by EOPs in theoretical research and practical applications, and propose potential directions for the development of EOPs in wastewater treatment to meet the growing demand for carbon neutrality. We believe that this review will offer crucial guidance and reference to enhance the application and dissemination of EOPs in organic wastewater treatment. [ABSTRACT FROM AUTHOR]