RSC Advances
PAPER
Novel lanthanide(III) 4-methylbenzoylhydrazide
complexes as precursors for lanthanide oxide
nanophotocatalysts
Cite this: RSC Adv., 2019, 9, 42010
a
*
S. A. Abou El-Enein,
and Metwally Madkour
A. M. Ali,a Y. K. Abdel-Monem,a M. H. Sennab
*
c
A series of metal complexes were prepared from separate reactions of lanthanide nitrate salts (La(III), Ce(III),
Sm(III), Gd(III) and Ho(III)) with 4-methylbenzoylhydrazide. The structures of the complexes were confirmed
by analytical studies, spectral measurements and thermal studies. Complexes were formed with different
stoichiometries of 1 : 2 and 1 : 3 (M : L). The ligand chelates by the nitrogen and oxygen atoms of the
amino and carbonyl groups of the hydrazide moiety in the neutral keto form. The coordination
compounds were converted to metal oxide nanoparticles (MONPs) through solid state thermal
decomposition as monocular source precursors. The obtained MONPs were investigated via XRD, TEM
and UV-Vis spectra. As a representative, CeO2 was utilized as a nanophotocatalyst to examine the
photocatalytic activity of the MONPs for methylene blue (MB) photodegradation. CeO2 showed high
removal of MB dye by 90.1% after UV illumination for 220 min. The reported method provides
a generalized and systematic method for the preparation of many metal oxide nanoparticles with
manageable and reproducible features.
Received 5th October 2019
Accepted 14th November 2019
DOI: 10.1039/c9ra08080e
rsc.li/rsc-advances
Metal oxide nanoparticles show a wide range of applications,
including catalysis, sensing, optics, semiconductors, solar cells,
1. Introduction
batteries and biotechnology. Also, metal oxide nanoparticles
have been used as nanophotocatalysts for the degradation of
methylene blue and Safranin-O dyes.8–12 The synthesis of metal
oxide nanoparticles from their corresponding metal complexes
is of great interest. This technique offers several unique
advantages over other methods, including facility, reproduc-
ibility, short reaction times, short washing and drying dura-
tions, and production of inorganic nanomaterials with narrow
size distributions.9
In this work, we aimed to synthesize lanthanide metal
complexes of lanthanum(III), cerium(III), samarium(III), gadoli-
nium(III), and holmium(III) with 4-methylbenzoylhydrazide
ligand. Structural characterization of all the prepared
compounds was performed based on elemental analysis, spec-
tral methods (UV-Vis, IR, 1H NMR, and mass spectroscopy),
molar electrical conductivity, magnetic susceptibility and
thermal analyses. Also, nano-metal oxides were prepared by
thermal degradation of the metal complexes, and their appli-
cations in wastewater treatment were studied through photo-
catalytic degradation of methylene blue.
Hydrazide compounds contain terminal NH2 groups and are
precursors for numerous synthesized Schiff and azo compounds.
Hydrazides and their derivatives have potential active sites; C]O,
NH and NH2 have the ability to coordinate with different metal
ions.1 Hydrazides and their derivative metal complexes have
applications in biological elds as insecticidal, acaricidal, nemati-
cidal, and antileishmanial agents and inhibit protease enzymes in
some parasitic species and diamine oxidases.1 Their lanthanide
complexes have luminescent and magnetic properties; thus, they
can be used in electroluminescent devices.2,3 Also, due to their
exhibited spectroscopic, magnetic, and chemical properties, these
lanthanide complexes have many useful applications compared to
other metal complexes. This is due to the uxional nature of lan-
thanide(III) ion, which possesses high and variable coordination
numbers as well as a lack of angular preference.4 Hydrazide
lanthanide complexes are an ongoing area of active research due to
their good antioxidant activities and their biological activities, such
as anticoagulation, antiallergic, antibacterial, anti-inammatory
and anticancer. Also, they have been used for treatment of burns.5–7
aDepartment of Chemistry, Faculty of Science, Menoua University, Shibin El Kom,
Egypt. E-mail: dr.saeyda_elenein@yahoo.com
bRadiation Chemistry Department, National Center for Radiation Research and
2. Experimental
2.1 Materials and methods
Technology, Cairo, Egypt
cDepartment of Chemistry, Faculty of Science, Kuwait University, P. O. Box: 5969,
13060, Kuwait. E-mail: metwally.madkour@ku.edu.kw
All chemicals were of analytical grade (BDH, Sigma or Aldrich)
and were used as received without further purication.
42010 | RSC Adv., 2019, 9, 42010–42019
This journal is © The Royal Society of Chemistry 2019