An electrochemically active green synthesized polycrystalline NiO/MgO catalyst: Use in photo-catalytic applications

被引：124

作者：

Fuku, X. ^{[1
,2
]}

Matinise, N. ^{[1
,2
]}

Masikini, M. ^{[3
]}

Kasinathan, K. ^{[1
,2
]}

Maaza, Malik ^{[1
,2
]}

机构：

[1] Univ South Africa, Coll Sci Engn & Technol, UNESCO UNISA Africa Chair Nanosci Nanotechnol, POB 392, Pretoria, South Africa

[2] Nat Res Fdn South Africa, Nanosci African Network NANOAFNET, Mat Res Dept, iThemba LABS, Old Faure Rd,POB 722, ZA-7129 Somerset West, Western Cape, South Africa

[3] Univ Western Cape, Dept Chem, SensorLab, ZA-7570 Cape Town, South Africa

来源：

MATERIALS RESEARCH BULLETIN | 2018年 / 97卷

关键词：

oxides; X-ray diffraction; optical properties; electrochemical properties; catalytic properties; NICKEL-OXIDE NANOPARTICLES;

D O I：

10.1016/j.materresbull.2017.09.022

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

For many years, research scientists have aided communities in their tremendous efforts towards environmental remediation. Due to their high physical and chemical stability, metal oxide nanoparticles (NPs) have been used as metal catalysts to remedy this issue. This article reviews green approaches for the synthesis of metal oxide nanoparticles, in aqueous bio-reductive polyphenols from punica granatum peel extract and the degradation of organic pollutants. The bimetallic nanocomposite of face-centred cubic NiO/MgO pseudocapacitors were successfully prepared via the polyphenols of punica granatum peel extracts. X-ray diffraction spectroscopy (XRD) successfully provide evidence of polycrystalline face-centre cubic nanocomposite (high crystallinity index (I-cry) > 1) while revealing their interplanar distance. The spherical and irregular particle distribution of the binary NiO/MgO nanocomposite (at different calcination temperatures) was assessed by high resolution-TEM. FTIR, GC MS and EDS provided evidence of the proposed mechanism during coordination between polyphenols and metal precursors. The popular "egg box model" is referred to in the case of polyphenols-metal interaction. The unique feature of two consecutive chelation site per repeat that provides a favourable entropic contribution to the inter-chain association is produced by this model governed by electrostatic interactions. Based on the obtained results, new structural models of Ni2+/Mg2+-polyphenols (punicalagin) complexes were proposed. UV-vis and Cyclic voltammetry confirmed the growth and band gap energies of the nanocomposite. NiO/MgO nanocomposite was found to be excellent photocatalysts for the degradation of methylene orange and methylene blue under the illumination of artificial light irradiation. The experiments demonstrated that MB in aqueous solution was more efficiently photo-degraded (87%) than MO (73%) using NiO/MgO nanocomposite as photocatalysts within 10 min of exposure. Conclusively, the nanocomposite was found to be more efficient compared to other reported oxides.

引用

页码：457 / 465

页数：9

共 25 条

[1]

[Anonymous], 2011, PHARM CHEM

[2] Environmental pollution and the global burden of disease [J].