Palladium Nanoparticles Decorated Graphene Oxide: Active and Reusable Nanocatalyst for the Catalytic Reduction of Hexavalent Chromium(VI)

Abstract

Today, the catalytic reduction of Cr(VI) to Cr(III) stands one of the most important challenges in the environmental chemistry and catalysis due to highly stable, contaminant and toxic nature of Cr(VI). In this study, we show that a new nanocatalyst system comprised of 3-aminopropyltriethoxysilane (APTS) stabilized palladium(0) nanoparticles grafted onto the surface of graphene oxide (Pd/GO) efficiently works in the catalytic reduction of Cr(VI) to Cr(III) under mild reaction conditions. Pd/ GO nanocatalyst was reproducibly prepared through two-steps procedure: (i) H 2 reduction of Pd(dba) 2 (dba = dibenzylideneacetone) in the presence of APTS in THF to synthesize colloidal APTS stabilized palladium(0) nanoparticles and then (ii) the deposition of 3-aminopropyltriethoxysilane stabilized palladium (0) nanoparticles onto the surface of graphene oxide (GO) by impregnation. The characterization of Pd/GO was carried out by advanced analytical techniques. The summation of the results acquired from these analyses reveals that the formation of well-dispersed and highly crystalline palladium(0) nanoparticles on the surface of GO. The catalytic performance of the resulting Pd/GO in terms of activity and stability was assessed in the catalytic reduction of Cr(VI) to Cr(III) in aqueous solution in the presence of formic acid (HCOOH) as a reducing agent. We found that Pd/GO nanocatalyst exhibits high activity (TOF = 3.6 mol Cr 2 O 7 2 À /mol Pd 3 min) and reusability (> 90% at 5 th reuse) in this catalytic transformation at room temperature.[a] Dr.

Nitrogen-doped lignin-derived carbon for catalytic reduction of hexavalent chromium via HCOOH-mediated hydrogenation

“…4c that the mass specific activity value of N@C-g-C 3 N 4 (2.21 mol K 2 Cr 2 O 7 g −1 min −1 at 323 K) is the highest among all samples, which is superior to the previously reported Pd-based catalysts (0.02–1.43 mol K 2 Cr 2 O 7 g Pd −1 min −1 ) in literatures. 18–21 As seen in Fig. 4d, the highest k value was calculated to be 2.98 min −1 for N@C-g-C 3 N 4 at 50 °C, higher than that of CoA–Pd heterogeneous catalyst ( k = 0.602 min −1 ) reported in literature.…”

Current Trends in the Optical Characterization of Two-Dimensional Carbon Nanomaterials

“…For another catalytic application, Cr 6+ should be reduced to Cr 3+ by graphene, and therefore the material was modified by 3-aminopropyltriethoxysilane-stabilized Pt nanoparticles. The presence of platinum and silicon in the corresponding EDX spectrum confirmed the successful functionalization of graphene (Celebi et al, 2017). Also, the sulfur contaminations in the high ppm range on the reduced graphene oxide sheets, introduced by the use of sulfuric acid during the fabrication process, have been identified by EDX (Alam et al, 2017).…”

Preparation, Characterization and First Application of Graphene Oxide‐Metformin‐Nickel for the Suzuki Cross‐Coupling Reaction

“…The X‐ray powder diffraction (XRD) pattern of the synthesized nanosheet catalyst (GO‐Met‐Ni) is observed in Figure . In this Figure, the broad peak at 2 Ɵ =24.4 is related to the functionalized GO with organic ligand . Also, there are three sharp peaks at 2 Ɵ =44.4, 51.7, 76.4 assigned to the (111), (200) and (220) planes, respectively which are attributed to nickel nanoparticles Ni(0) in structure of catalyst (PDF #04‐0850)…”