Gold nanoparticle and graphene oxide incorporated strontium crosslinked alginate/carboxymethyl cellulose composites for o-nitroaniline reduction and Suzuki-Miyaura cross-coupling reactions

Self-organized strontium ion crosslinked alginate/carboxymethyl cellulose composite materials with gold nanoparticles (Au-NPs) and graphene oxide (GO) were effectively fabricated using dissipative convective procedures followed by the freeze-drying method. Composite gels were characterized by using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy with Energy dispersive X-ray analysis (SEM-EDAX) and transmission electron microscopy (TEM) analysis. Moreover, thermal, mechanical and rheological properties were also performed to identify their strength and stability. The results revealed that Sr/Alg/CMC/Au and Sr/Alg/CMC/GO/Au composites showed remarkably porous structures with ordered capillaries; rheologically gel-like structures with high mechanical strength. Moreover, composites were tested for the reduction of o-nitroaniline and Suzuki-Miyaura cross-coupling reaction. The Sr/Alg/CMC/GO/Au composite competently reduced the o-nitroaniline within 2 min (k = 4.86 x 10(-2) s(-1)) with recyclability up to 7 consecutive cycles and also displayed 98% isolated yield (TOF value is 4900 h(-1)) for Suzuki-Miyaura cross-coupling reaction with 6 cycles recyclability. This approach of using nanoparticles incorporated composite systems as reusable catalysts opens a door of new materials for various catalytic applications. (C) 2017 Elsevier Inc. All rights reserved.