composite materials were synthesized as filler materials of packed columns for
simultaneous filtration disinfection as an alternative portable water treatment process.
Alginate was chosen as the immobilization/delivery material due to its natural
abundance and biocompatibility. These Ag,
Au/Ag
-alginate composite beads were
packed to form porous columns through which bacteria containing water was passed.
Composite beads prepared using different stabilisator were found to be effective in
disinfecting the E. coli to different extents. With alginate composite beads, the
disinfection efficiency is high even with a HRT 2-5 min. Different efficiency of
composite samples obtained with different stabilizers indicates different degrees of
antibacterial action of plasma-chemically synthesized silver nanoparticles. In addition,
this may be due to the different structural formation of the composite and the release
mechanisms of silver ions.
Bimetallic nanoparticles, which are composed of two metal elements in a particle,
exhibit much higher catalytic activity than respective monometallic ones due to new
bi-functional or synergistic effects, so-called a ligand and/or an ensemble effect. The
catalytic activity for glucose oxidation was investigated for thus-prepared Ag/Au
bimetallic nanoparticles with various compositions. The highest activity (15,880 mol-
glucose h
−1
mol-metal
−1
) was observed for the Ag/Au nanoparticle prepared with
Ag/Au ratio of 0.5/1, the activity being 18-30 times higher than that of original
monometallic Au nanoparticles under the same conditions. A novel heterogeneous
Au/Ag bimetallic nanocatalyst have been synthesized and supported on layer double
hydroxide (LDH) by a simple wet plasma-chemical process.
Au/Ag bimetallic NPs
supported on LDH showed a high rate of conversion of 4-NP to 4-AP. The different
compositions of as-synthesized Au/Ag bimetallic nanoparticles were utilized for the
catalytic reduction of 4-nitrophenol [7]. The highest activity was observed for the
Au/Ag nanoparticles prepared with Au/Ag ratio at 0.5:3 and the activity became 15 to
65 times higher than that of original monometallic Au or Ag nanoparticles.
Ag,
Ag/Au - doped Zr(IV) and Al(III) oxyhydroxides adsorbents were
synthesized by combination of sol-gel and reagentless plasma-chemical methods. The
offered technique allows to receive the highly homogenized metal oxyhydroxides sols
with Ag
0
impurities, which is confirmed by the presence of a peak Ag
,
Ag/Au NPs in
composite sol. Proposed method allows to obtain nanostructured adsorbents, which are
characterized by high surface area from 300 to 530 m
2
/g and pore size >2 nm. The
effectiveness of the produced sorbents was estimated by reducing the concentration of
total solids, manganese ions, colony count 22°C and Coliform bacteria in natural
underground water (Table 3).
A comparative analysis shows the efficiency of Ag
0
, Au, Ag/Au NPs additive
during sol-gel synthesis of Zr(IV) and Al(III) to produce adsorbent for water
purification which can reduce both the inorganic and microbiology impurities such as
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