Abstract:
Mn304 nanoparticles were prepared by forced hydrolysis of aqueous
manganese(lJ) acetate, Mn(OOCCH3h, solution. Starch was used as
capping agent to prevent the agglomeration of the nanoparticles thus
formed in the colloidal mixture, 0.4 M Mn(OOCCH3)2 precursor in
saturated aqueous solution of starch was aged for 2,6, and 12 h at a
temperature 80 °C . The nanoparticles were then collected by
reducing the volume of suspension on mild heating followed by
ethanol extraction. The more uniform and well-dispersed particles
were obtained by heating the reaction mixture for 2 h. The
nanoparticles thus obtained were characterized by means of EDX,
XRD, IR, and SEM. The results showed that the Mn304 nanoparticles
were single phase, spherical, and uniformly dispersed. The average
crystallite size was calculated from the XRD data to be approximately
10 nm.
Polyaniline (PAN!) was synthesized from aniline by using potassium
dichromate, K2Cr207, as an oxidizing agent. The dispersion of the
Mn304 nanoparticles into PANI matrix was achieved by the addition of
nanoparticles suspension to the sediment of PAN!. The conductivity
of the PANI/Mn304 matrix was measured to be 20.82 x 10-6 Scm-1 and
found to be higher than that of PANI, 3.72 x 10-6 Scm"l.
Mn304 nanoparticles were tested to perform the polymerization of
aniline instead of conventional chemical polymerization by an oxidant.
The nanoparticles can effectively polymerize aniline to yield PAN!.
The PANI thus prepared was found to be more conductive because
of its compact and modified morphology as seen from SEM,
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The efficiency of the Mn304 nanoparticles on the decolorization of
methylene blue (MB) dye has been studied in presence of H2S04.
Effect of MB concentration, amount of nanoparticles required,
influence of acid concentration, and function of time on MB
decolorization were also investigated by employing UV-Visible
spectroscopy, It was found from these investigations that Mn304
nanoparticles can efficiently and rapidly decolorize MB in adequately
acidic media.
The Mn304 nanoparticles was also successfully employed to
deco!orize another-textile dye procion red {PRJ and an industrial dye
effluent. UV-Visible spectra of the solutions were taken in all cases to
measure the extent of decolorization.
Sensitivity of the Mn304 nanoparticles suspension was tested on
various pathogenic organisms at two different pH, 3.3 and 6.2. The
nanoparticles were found to be sensitive against Vibrio cholerae,
Shigella sp., Salmonella sp., and Escherichi coli bacteria, which are
responsible for cholera, dysentery, typhoid, and diarrhoea diseases,
respectively.
