A Cobalt Tandem Catalyst Supported on a Compressible Microporous Polymer Monolith

Abstract

A compressible microporous polymer monolith (MPM) was prepared by performing the Sonogashira–Hagihara reaction between 1,4-diiodobenzene and 1,3,5-triethynylbenzene in a gel state without stirring. MPM was functionalized via the click reaction with 1,3,5-tris(azidomethyl)-2,4,6-trimethylbenzene and 2,6-diethynylpyridine. MPM showed superhydrophobicity but became hydrophilic after the click reaction. The functionalized MPM (F-MPM) had polar triazole groups generated by the click reaction, which were used as coordination sites for Co(II) ions. Cobalt nanoparticles were loaded to F-MPM through in situ reduction of coordinated Co(II) ions to produce a monolithic Co heterogeneous catalyst (Co-MPM). The microscopic study showed that MPM, F-MPM, and Co-MPM consisted of fiber bundles, together with spherical particles on the micrometer scale. Co-MPM was used for tandem catalysis. Co-MPM promoted the reaction of dehydrogenation of ammonia borane and hydrogenation of nitro compounds in one pot to give amine products. The reactions with the compression and release process were much faster compared with the reactions performed under the stirring conditions, suggesting that the repeated compression and release facilitated interfacial contact between the reactants and active sites in Co-MPM.

The Hydrogen‐Storage Challenge: Nanoparticles for Metal‐Catalyzed Ammonia Borane Dehydrogenation

“…For the hydrolytic dehydrogenation of AB, Co@PCC (7% Co) achieved a TOF = 90.1 min -1 . Beside the activity progress achieved using monometallic Co NPs systems for AB hydrolytic dehydrogenation, investigation also met success with further developing magnetic, 164 tandem-reactive, 165 and photocatalytic systems. 166,167,168 Co(0) NPs supported on ceria (Co/CeO 2 ) were prepared from the reduction of CoCl 2 previously impregnated on the surface of ceria nanopowders.…”

Unprecedented Processable Hypercrosslinked Polymers with Controlled Knitting

“…Among these HCPs monoliths, HCPs monolith 2 could bear a load of 65 MPa, which, in fact, is much higher than those of the reported carbon monoliths [31] and MOPs monoliths. [32][33][34][35][36] Surprisingly, the Young modulus of HCPs monolith 2 was found to be nearly 10 000 times greater than that of the reported PIM-1 monoliths (33 KPa). [37] Therefore, the HCPs monolith 2 undoubtedly represents an No.…”

Designing Internal Hierarchical Porous Networks in Polymer Monoliths that Exhibit Rapid Removal and Photocatalytic Degradation of Aromatic Pollutants

“…[ 56 ] When exposed to an 0.1 × 10 −3 m aqueous solution of the molecules at room temperature, the materials rapidly and thoroughly adsorbed them from water within 1 min, while being manually compressed and released successively in the solutions when monitored by UV–vis spectroscopy (Figure 7b), following reported procedures. [ 29,31 ] Likewise, over 80% of the model pollutants were removed from the solution only after 10 min of exposure (Figure 7c). The less compressible, control sample (CDPs‐AAm) in the same weight behaved similarly under the same conditions, but the removal efficiency was found to be much lower, nearly one‐third of that from CDPs‐HIPE with the intrinsic pores.…”

“…[ 26–28 ] On the contrary, the materials recently have been synthesized as a monolithic network or incorporated in bulk materials via a bottom‐up approach, which further enables diverse applications such as gas adsorption, separation, catalysis, sensing, and energy storage. [ 29–34 ] In particular, we reported melamine‐based MOPs that could form HIPEs as a Pickering agent. [ 35,36 ] However, the MOP‐type agents showed limited emulsifying capabilities (internal phase, ≤60%) or needed auxiliary components such as silver nanoparticles to overcome lower, intrinsic amphiphilicity of the network.…”