3D Porous Network Structured Co and Ni Catalysts for 4-Nitrophenol Reduction Reaction

3D porous network structured cobalt and nickel bead catalysts were easily greenly fabricated in the presence of chitosan for the catalytic reduction of 4-nitrophenol to 4-aminophenol. Physicochemical properties and morphology were determined using XRD, nitrogen adsorption/desorption, FT-IR, and SEM /EDS analyses. While the XRD pattern and FT-IR spectra showed the presence of chitosan, peaks related to cobalt and nickel species were not observed. Nitrogen adsorption/desorption isotherms exhibited a behavior indicating of micro-mesoporous structure. The surface area (41.24 m2/g), total pore volume (0.035 cm3/g), and pore diameter (3.59 nm) values of Ni@chitosan catalyst were acquired higher than that of Co@chitosan catalyst. EDS mapping showed that cobalt and nickel were homogeneously distributed in the chitosan structure. Co@chitosan exhibited higher catalytic activity. Reaction rate constant values were found as 0.498 and 0.074 min-1 for Co@chitosan and Ni@chitosan, respectively. The catalytic activity of the catalysts was competitive and guided for 4-nitrophenol reduction applications.