Dual-Functional Grafted Electrospun Polymer Microfiber Scaffold Hosted Palladium Nanoparticles for Catalyzing Redox Reactions

Abstract

Porous poly(ether sulfone) (PES) microfiber mat has been prepared by electrospinning technique using the optimized conditions. The reducing moiety has been attached covalently to the PES microfiber mat by UV‐graft polymerization of glycidylmethacrylate, and reacting subsequently with hydrazine via epoxy ring opening. The grafted polymer shell around porous microfiber has been found to perform the reduction of precursor ions by grafted hydrazine which leads to the nucleation and growth of Pd nanoparticles (NPs) on the host matrix itself. The catalytic activities and reduction kinetics of the microfiber hosted Pd NPs have been examined in the reductions of CrVI and UVI ions with in situ hydrogen generated by the formic acid decomposition at 50 °C, and p‐nitrophenol with borohydride/hydrazine at room temperature. Thus, hosted Pd NPs exhibit higher catalytic activity with respect to that reported in literature, and also the host matrix provides reasonably good recyclability and shelf‐life to Pd NPs.

Porous polymers and metallic nanoparticles: A hybrid wedding as a robust method toward efficient supported catalytic systems

“…Another interesting recent work is that from Pandey's team [140], who used electrospinning to prepare poly(ether sulfone) (PES) fibers and took advantage of the presence of the ether sulfone moieties to perform photolysis under UV irradiation to initiate the growth of polyGMA chains. The pendant oxirane groups were then opened with hydrazine providing directly attachment of the reducing agents on the support surface.…”

Cadmium(II)‐Loaded Fe3O4@MPTS Nanoparticles: Preparation and Application as Catalyst for C‐N Coupling Reactions

“…It is interesting to note that the toxicities of the heavy metal ions are highly dependent upon their chemical forms. For example, Cr(VI) ions can be converted to lesser toxic and labile Cr(III) form by the catalytic reduction …”

“…For example, Cr(VI) ions can be converted to lesser toxic and labile Cr(III) form by the catalytic reduction. [8][9][10] In recent years, several attempts have been made to prepare low-cost and most effective adsorbents for the removal of toxic metal ions. Some of these adsorbents are fly ash, [11] fertilizer industrial waste, [12] titanium oxide, [13] red mud, [14] clay montmorillonite, [15][16] sawdust, [17] biomass materials, [18][19] yeast and microorganism.…”

Palladium Nanoparticles Hosted in Poly(ethylenimine) and Poly(ethylene glycol methacrylate phosphate) Anchored Membranes for Catalyzing Uranyl Ions Reduction and Mizoroki–Heck Coupling Reaction

“…It has been reported that the neutral weak basic (no ion-exchange sites) membrane not only provides the optimum interactions with the nanocatalyst but also holds high amount of the metal NPs. 7,19 Among the noble metals, palladium (Pd) has been studied extensively as the prime catalyst for the applications in industrial and biological important coupling reactions involving carbon−carbon and carbon-heteroatom coupling reactions, 20−22 remediation of toxic ions including nitrite reduction, 23 synthesis of nanoreactors, 24 reduction of Cr 2 O 7 2− /CrO 4 2− anions to Cr 3+ ions, 25,26 and reduction of UO 2 2+ to U 4+ ions 5,6 having applications in nuclear industries. Palladium and Pd NPs supported on solid matrices (heterogeneous) have been extensively used in many organic coupling reactions 18,27 and inorganic transformations which found to exhibit better catalytic activity compare to their traditional homogeneous analogues such as Pd(OAc) 2 and PdCl 2 .…”

“…In general, this physical instability could be avoided by using appropriate surfactants during NPs syntheses. − However, these NPs suspended in colloidal solutions are difficult to handle/withdraw, and also surfactant coatings on NPs may block the catalytic sites, which would slower the reaction kinetics by hindering the interaction of reactants with the catalyst surface. These problems can be addressed by immobilizing the NPs on insoluble solid supports such as synthetic polymer membrane as given in our earlier publications, − silica (SiO 2 ), − alumina (Al 2 O 3 ), carbon nanomaterials (carbon nanotubes, graphene oxide), − TiO 2 film, superparamagnetic materials (Fe 3 O 4 ), etc. − Among the solid supports, the porous polymeric membrane provides not only better physical and chemical stability but also high accessibility of the NPs to reactants. It is also possible to tune the size and shape of the NPs, and have added advantage of ease of handling/withdrawing for recycling.…”