Flower-like 3-dimensional hierarchical Co3O4/NiO microspheres for 4-nitrophenol reduction reaction

Amutha Chinnappan; Saeideh Kholghi Eshkalak; Chinnappan Baskar; Marziyeh Khatibzadeh; Elaheh Kowsari; Seeram Ramakrishna

doi:10.1039/c8na00029h

Flower-like 3-dimensional hierarchical Co₃O₄/NiO microspheres for 4-nitrophenol reduction reaction

Nanoscale Adv. 2018 Sep 13;1(1):305-313. doi: 10.1039/c8na00029h. eCollection 2019 Jan 15.

Authors

Amutha Chinnappan¹, Saeideh Kholghi Eshkalak^{1

2}, Chinnappan Baskar³, Marziyeh Khatibzadeh², Elaheh Kowsari⁴, Seeram Ramakrishna¹

Affiliations

¹ Center for Nanofibers and Nanotechnology, Department of Mechanical Engineering, National University of Singapore Singapore 119260 mpecam@nus.edu.sg seeram@nus.edu.sg.
² Department of Polymer Engineering and Color Technology, Amirkabir University of Technology Tehran Iran.
³ THDC Institute of Hydropower Engineering and Technology Tehri, Uttarakhand Technical University Dehradun Uttarakhand India 249001.
⁴ Department of Chemistry, Amirkabir University of Technology Tehran Iran.

Abstract

Aromatic nitro compounds are toxic and not biodegradable. Therefore, the elimination of nitro groups is very important. Metal catalysts play an important role in the catalytic transformation. We present here flower-like 3D hierarchical Co₃O₄/NiO microspheres, which are prepared by a chemical precipitation method. The as-prepared catalyst is characterized by FTIR, SEM, TEM, EDS, XRD, XPS and N₂ sorption isotherms. They have shown different morphologies such as flower, nanocubes, and hexagonal structure at different calcined temperatures. The synthesized catalyst is tested and used for the reduction of 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride as a reducing agent. The reaction takes place in an aqueous medium at room temperature. The bimetallic catalyst Co₃O₄/NiO showed good performance and reusability.