Boat‐, Cuboid‐, and Dumbbell‐Shaped Hierarchical Morphology of Cerium (IV) Hydroxidophosphate Materials for Oxidative Coupling Reaction

Abstract

A simple hydrothermal approach was used to obtain boat‐, cuboid‐, and dumbbell‐shaped hierarchical morphology of cerium (IV) hydroxidophosphate materials. The period of the reactions, pH, and types of bases play crucial roles in tuning the morphology of the material. PXRD, FE‐SEM, HR‐TEM, FT‐IR, XPS, EDX, and EPR spectroscopies were used to analyze the materials. FE‐SEM and HR‐TEM analysis show that the materials have hierarchical morphology. According to XPS and EPR analysis, the materials comprise a redox‐active Ce3+/Ce4+ couple. The thiol to disulfide oxidative coupling reaction is synergistically boosted by the hierarchical morphology and redox‐active Ce3+/Ce4+ couple. The catalyst has excellent catalytic activity both in aqueous as well as protic organic solvents. However, the catalyst exhibited no reactivity in common organic solvents such as CH3CN, DCM, and THF. The catalytic reaction was thoroughly investigated in the presence of various solvents, catalyst amounts, oxidising agents, and substrates. In the presence of H2O2, the yield is 99%, whereas in the presence of air, it is 79%. We found high yields for several aromatic thiols but aliphatic thiols exhibited relatively poor yields under identical conditions.

Design and assembly of porous organic cages

“…Recent developments have showcased POCs as emerging molecular building blocks for constructing high-quality covalent organic frameworks (COFs) through post-synthetic linker exchange strategies. 162–165 This illustrates the potential of POCs to dynamically transform into polymeric organic frameworks.…”

Recent Developments on the Catalytic and Biosensing Applications of Porous Nanomaterials

“…Although porous oxide and phosphate nanostructures have smaller surface areas than silica, they provide a great platform for heterogeneous catalytic transformations because of their high crystallinity, thermal stability, and number of active sites [113][114][115][116][117][118][119]. Akbari et al reviewed the applications of metal-oxide NPs from groups 4 to 9 and 11 for the selective oxidation of alkenes, alcohols, and aldehydes [120].…”

“…Sarkar et al recently prepared boat-, dumbbell-, and cuboid-shaped cerium hydroxidophosphate materials via sol-gel-mediated hydrothermal synthesis and employed them for the oxidative coupling of thiols to disulfides in the presence of H 2 O 2 and air [113]. Bifunctional Zn-Ti-based nanocatalysts exhibited catalytic activities in oxidation and benzylation reactions, demonstrating the high efficiency and stability of this heterogeneous support for organic transformations [122].…”

Solar Light-Driven Molecular Oxygen Activation by BiOCl Nanosheets: Synergy of Coexposed {001}, {110} Facets and Oxygen Vacancies

“…The design and fabrication of facet-controlled single-crystalline BiOCl semiconductors with well-defined morphology have garnered significant interest due to their wide range of applications in photocatalysis. − These applications include CO 2 reduction, ammonia synthesis, , oxidation of amine and alcohol compounds, water splitting, as well as dyes and antibiotic degradations . The unique electronic and chemical structures of these semiconductors are a result of their single-crystalline structure with varying shapes, which can be attributed to the different electronic and atomic arrangements within the crystal. − BiOCl exhibits a unique two-dimensional layered structure, consisting of interleaved [Bi 2 O 2 ] 2+ slabs and double chloride atom slabs . These distinct layers play a crucial role in preventing the recombination of photogenerated electrons and holes by creating interior electric fields between the [Bi 2 O 2 ] 2+ and chloride layers. , Additionally, the structure helps minimize surface trapping of photogenerated electrons and holes through the presence of low-dangling bonds resulting from the covalently bonded layers .…”