Restructuring of silica-pillared clay (SPC) through posthydrothermal treatment and application as phosphotungstic acid supports for cyclohexene oxidation
“…20). 241 A new type of nanohybrid material H 6 P 2 W 18 O 62 /nanoclinoptilolite was fabricated, and performed as an efficient and reusable catalyst in the mild and one-pot condensation of different acetophenones. 242 These types of zeolites contain open tetrahedral cages, generating a system of channels, the sizes of which are determined by the content of silicon.…”
“…20). 241 A new type of nanohybrid material H 6 P 2 W 18 O 62 /nanoclinoptilolite was fabricated, and performed as an efficient and reusable catalyst in the mild and one-pot condensation of different acetophenones. 242 These types of zeolites contain open tetrahedral cages, generating a system of channels, the sizes of which are determined by the content of silicon.…”
“…The pores appear in lighter contrast between the layers which consists of uniform layered structure. Furthermore, the uniform gallery pores can be observed between the dark layers (Gao et al., 2012; Mao et al., 2009, 2014, 2015; Yang et al., 2013). Figure 5.TEM images of Mt, TDA-Mt, mesoporous Mt, and mesoporous Ti-Mt.…”
Adsorption of paraquat and pirimiphos-methyl in water was performed on four adsorbents including montmorillonite (Mt), organoclay (TDA-Mt) from intercalation of Mt with tetradecylammonium chloride, and mesoporous Mt from intragallery templating method (with and without Ti addition). The adsorbents were characterized by X-ray diffraction, N 2 adsorptiondesorption, and transmission electron microscopy. Paraquat adsorption isotherms followed Langmuir model and the adsorption capacity was as follows: TDA-Mt > Mt > mesoporous TiMt > mesoporous Mt. The adsorption mechanism on TDA-Mt and Mt might be via ion exchange. The adsorption on mesoporous samples was on the external surface with negative charge. The presence of Ti enhanced the adsorption capacity. Pirimiphos-methyl adsorbed on negative charge of the external surface of Mt samples. The adsorbed amount increased with the initial concentration due to a strong intermolecular interaction.
“…For instance, silica pillared clay (SPC) supported PTA has been prepared via post‐hydrothermal treatment. The as‐synthesised material possessed a high surface area of 686.2 m 2 g −1 with a pore size of 2.6 nm [50] …”
“…Kim et al ., applied HPA deposited on N 2 ‐doped mesoporous carbon(N‐MC) for methacrolein oxidation, and showed that the HPA/N‐MC has better catalytic activity than HPA/SBA‐15, presumably due to the better dispersion of keggin clusters on the n‐MC surface via chemical linkage [45b] . In another effort, Mao and co‐workers, applied silica‐pillared clay supported PTA as a catalyst for cyclohexene oxidation, the effective interaction between PTA and clay substrate and increased surface area leading to high conversion and selectivity [50] …”
Functionalized nanoporous heteropoly acids (HPAs) have garnered significant attention in recent years due to their enhanced surface area and porosity, as well as their potential for low‐cost regeneration compared to bulk materials. This review aims to provide an overview of the recent advancements in the synthesis and applications of functionalized HPAs. We begin by introducing the fundamental properties of HPAs and their unique structure, followed by a comprehensive overview of the various approaches employed for the synthesis of functionalized HPAs, including salts, anchoring onto supports, and implementing mesoporous silica sieves. The potential applications of functionalized HPAs in various fields are also discussed, highlighting their boosted performance in a wide range of applications. Finally, we address the current challenges and present future prospects in the development of functionalized HPAs, particularly in the context of mesoporous HPAs. This review aims to provide a comprehensive summary of the recent progress in the field, highlighting the significant advancements made in the synthesis and applications of functionalized HPAs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
