Facile Synthesis and Tunable Porosities of Imidazolium-Based Ionic Polymers that Contain In Situ Formed Palladium Nanoparticles

Electron-Rich Triazine-Conjugated Microporous Polymers for the Removal of Dyes from Wastewater

Conjugated microporous polymers (CMP) as porous functional materials have received considerable attention due to their unique structures and fascinating properties for the adsorption and degradation of dyes. Herein, a triazine-conjugated microporous polymer material with rich N-donors at the skeleton itself was successfully synthesized via the Sonogashira-Hagihara coupling by a one-pot reaction. These two polymers had Brunauer-Emmett-Teller (BET) surface areas of 322 and 435 m²g^-1 for triazine-conjugated microporous polymers (T-CMP) and T-CMP-Me, respectively. Due to the porous effects and the rich N-donor at the framework, it displayed a higher removal efficiency and adsorption performance compared to cationic-type dyes and selectivity properties for (methylene blue) MB⁺ from a mixture solution of cationic-type dyes. Furthermore, the T-CMP-Me could quickly and drastically separate MB⁺ and (methyl orange) MO^- from the mixed solution within a short time. Their intriguing absorption behaviors are supported by ¹³C NMR, UV-vis absorption spectroscopy, scanning electron microscopy, and X-ray powder diffraction studies. This work will not only improve the development of porous material varieties, but also demonstrate the adsorption or selectivity of porous materials for dyes from wastewater.

N-Heterocyclic carbenes and their precursors in functionalised porous materials

Though N-heterocyclic carbenes (NHCs) have emerged as diverse and powerful discrete functional molecules in pharmaceutics, nanotechnology, and catalysis over decades, the heterogenization of NHCs and their precursors for broader applications in porous materials, like metal-organic frameworks (MOFs), porous coordination polymers (PCPs), covalent-organic frameworks (COFs), porous organic polymers (POPs), and porous organometallic cages (POMCs) was not extensively studied until the last ten years. By de novo or post-synthetic modification (PSM) methods, myriads of NHCs and their precursors containing building blocks were designed and integrated into MOFs, PCPs, COFs, POPs and POMCs to form various structures and porosities. Functionalisation with NHCs and their precursors significantly expands the scope of the potential applications of porous materials by tuning the pore surface chemical/physical properties, providing active sites for binding guest molecules and substrates and realizing recyclability. In this review, we summarise and discuss the recent progress on the synthetic methods, structural features, and promising applications of NHCs and their precursors in functionalised porous materials. At the end, a brief perspective on the encouraging future prospects and challenges in this contemporary field is presented. This review will serve as a guide for researchers to design and synthesize more novel porous materials functionalised with NHCs and their precursors.

Selective Hydrogenation by Carbocatalyst: The Role of Radicals

The selective hydrogenation of the nitro moiety is a difficult task in the presence of other reducible functional groups such as alkenes or alkynes. We show that the carbon-based (metal-free) catalyst can be used to selectively reduce substituted nitro groups using H₂ as a reducing agent, providing a great potential to replace noble-metal catalysts and contributing to simple and greener strategies for organic synthesis.

Highly efficient aqueous phase reduction of nitroarenes catalyzed by phosphine-decorated polymer immobilized ionic liquid stabilized PdNPs

Phosphino-decorated polymer immobilised ionic liquid-stabilised PdNPs are highly efficient catalysts for the aqueous phase hydrogenation and transfer hydrogenation of aromatic nitro compounds in batch and continuous flow.

Defect-rich Ni–Ti layered double hydroxide as a highly efficient support for Au nanoparticles in base-free and solvent-free selective oxidation of benzyl alcohol

Defect-rich Ni–Ti layered double hydroxide supported Au nanoparticles exhibited greatly enhanced activity in the oxidation of benzyl alcohol.

Accelerated catalytic activity of Pd NPs supported on amine-rich silica hollow nanospheres for quinoline hydrogenation

The ultra-small Pd NPs stabilized by the amine-rich silica hollow nanosphere with a TOF as high as 5052 h⁻¹ are among the most active solid catalysts for quinoline hydrogenation. The high catalytic activity could be mainly attributed to the ultra-small particle size and high surface electron density of Pd NPs.

Palladium nanoparticles supported on a carbazole functionalized mesoporous organic polymer: synthesis and their application as efficient catalysts for the Suzuki–Miyaura cross coupling reaction

Pd nanoparticles supported on a carbazole functionalized mesoporous organic polymer exhibit high performance in the Suzuki–Miyaura cross coupling reaction with good catalytic activity, substrate adaptability and recyclability.

Gold nanoparticles supported by imidazolium-based porous organic polymers for nitroarene reduction

Gold nanoparticles supported by imidazolium-based porous organic polymers exhibit higher catalytic activity, selectivity and recyclability than those supported by a non-ionic analogue.