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We report a two-step process for the immobilization of gold nanocubes (Au-NCs) on a glass surface using a combination of extraction and exchange reaction using poly (sodium 4-styrenesulfonate) (PSS) and trisodium citrate (TSC). Cetyltrimethylammonium chloride (CTAC) stabilized gold nanocubes (CTAC/Au-NCs) synthesized by a microfluidic synthesis procedure were successfully deposited on silane-modified glass substrate after extraction of excess CTAC using chloroform followed by exchange of CTAC to TSC on the surface of Au-NCs. Further, TSC/Au-NCs were found to be highly stable and suitable for microfluidic sensing of different glucose concentrations using localized surface plasmon resonance (LSPR) spectroscopy offering an improved sensitivity (126.37 nm/RIU).

In this study, we developed a facile synthetic method for the preparation of nanostructured sodium cobalt fluoride (NaCoF3). Uniform NaCoF3 nanoparticles with small-crystallite size were synthesized through a simple solvothermal process using relatively inexpensive precursors. The NaCoF3 particles obtained were composed of small nanoparticles (∼20 nm) assembled to form large nanoparticle clusters (NPCs, ∼200 nm). This unique nanostructure provided a large surface area (>40 m2 g−1) of NaCoF3. Furthermore, the effects of reaction conditions and an essential additive (trisodium citrate) were also investigated using analytical techniques, and the importance of the optimal conditions to obtain uniform NaCoF3 NPCs without impurities was demonstrated. We expect that this synthetic method will initiate further research into the development of various nanostructured sodium metal fluorides and their applications.

This paper presents a facile, and ecofriendly method to prepare colloidal silver nanoparticles (AgNPs) at room temperature using bulk silver bars, bi-distilled water, trisodium citrate, and a direct-current voltage source. AgNP formation was confirmed and characterized by ultraviolet–visible spectroscopy, transmission electron microscopy and X-ray diffraction. Their antibacterial activity was examined by disc diffusion and minimum inhibitory concentration (MIC) techniques against three bacterial strains, including the Gram-positive bacteria Staphylococcus aureus and the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa . Results showed that the size of AgNPs formed was about 19.7±4.3 nm with nearly spherical shape and high purity. The antibacterial activity of as-prepared AgNPs was determined through zones of inhibition against the growth of three bacterial strains on agar. MIC analysis showed that S. aureus had resistance to AgNPs that was about 2–3 times higher than those of E. coli and P. aeruginosa , and that resistance ability depended on the bacterial concentrations inoculated. This work revealed the effective method of synthesizing a large quantity of colloidal AgNPs with high antibacterial effectiveness and potential application in different fields.

Uniform and well-dispersed SrMoO 4 hierarchical microspheres have been synthesized via a facile citrate-assisted hydrothermal approach. The as-obtained particles are non-aggregated with narrow size distribution and are composed of closely packed nanoparticles. The reaction conditions, including trisodium citrate additive, pH value of the initial solution, as well as reaction temperature and time, have great effect on the particle size and morphology of the products. The as-synthesized SrMoO 4 :Ln 3+ (Ln=Eu, Tb, Dy, and Sm) samples show intense characteristic emissions with different colors under ultraviolet excitation, which may find potential applications in the fields of fluorescent lamps, color displays, and light-emitting diodes (LEDs).

Uniform flower-like ZnO superstructures were rapidly prepared on a large scale via a simple and inexpensive solution approach at room temperature. These ZnO microflowers having a mean diameter of about 4 μm, were assembled by numerous porous ZnO nanosheets with a thickness of 40 nm. The concentration of trisodium citrate and sodium hydroxide has great influence on the morphology of the final products, respectively. At room temperature, the photoluminescence (PL) spectrum showed that the ZnO microflowers exhibited a very weak UV emission peak located at 380 nm and a relatively strong green emission peak centered at 565 nm. This economical and efficient work may provide new insights into the fabrication of other metal oxide microstructures.

This study is to understand the effect of Nb 2 O 5 on the formation and morphology of LiNbO 3 particles during hydrothermal synthesis. Trisodium citrate (Na 3 C 6 H 5 O 7 ) is for the first time used as a selective crystallographic growth suppressing agent. The morphology of LiNbO 3 is examined using scanning electron microscopy and the crystal structure of the material is characterized using X-ray diffraction. The morphology of LiNbO 3 evolves into novel flower structures as the synthesis time increases to 5 days. The crystal structures of the synthesized materials are consistent with the morphology evolution.

Uniform BaWO4:Eu3+ hierarchical submicrospheres have been prepared via a simple hydrothermal route. The as-synthesized BaWO4:Eu3+ particles are well-dispersed with narrow size distribution and are assembled by many tiny nanoparticles. During the synthesis process, the trisodium citrate additive plays a crucial role for the formation of BaWO4:Eu3+ submicrospheres. Under ultraviolet light excitation, the spherical BaWO4:Eu3+ phosphor exhibits much stronger luminescence than that shuttle-like BaWO4:Eu3+ sample prepared without adding trisodium citrate as additive. The spherical luminescent material may find potential applications in fields of lighting, displays, and nanodevices. This simple synthesis route may be extended to prepare other tungstate functional materials with well-defined morphologies.

A simple and effective method has been demonstrated to synthesize Au/Pt/Ag trimetallic nanocomposites by reduction of the corresponding ions with trisodium citrate using microwave (MW) irradiation. The prepared trimetallic nanocomposites have been characterized using X-ray diffraction, absorbance, high resolution-scanning and transmission electron microscopic techniques. The prepared trimetallic nanocomposites containing Au nanowires and Ag/Pt bimetallic nanoparticles have been found. The surface-enhanced Raman scattering (SERS) has been carried out with the addition of 7-azaindole in trimetallic nanocomposites demonstrated that higher Pt content in the surface.

In this paper, hierarchical porous ZnO microspheres were successfully synthesized by calcining the microspheric zinc hydroxide carbonate (ZHC) precursor, which were the precipitate products of a hydrothermal reaction by zinc nitrate hexahydrate and urea in the presence of trisodium citrate. The as-prepared ZnO microspheres with diameters of 4–5 μm were assembled by numerous porous nanosheets which had the uniform thickness of about 10 nm. The photocatalytic activity of the ZnO microspheres was evaluated by photodegradation reaction of methylene blue (MB). The as-prepared ZnO microspheres exhibited a significantly enhanced photocatalytic activity than commercial ZnO and TiO2. This was mainly attributed to the larger specific surface area and stability against aggregation.

Hydroxyapatite (HA) microspheres were hydrothermally synthesized by using propionamide (PA) and trisodium citrate (Cit). The capability of PA and Cit to control ions release in synthesis solution contributed to the formation of hierarchical porous structure. The effect of hydrothermal time was investigated to explore the formation mechanism of HA microspheres. The result demonstrated that the morphology of products transformed from microsheets to microspheres as reaction time increased. Combining with the theory of Ostwald ripening, it was proposed that earlandite nanosheets as primary building units were firstly formed from nucleation and then self-assembled into the final HA microspheres.

Size-controlled synthesis of hydroxyapatite nanorods was carried out by chemical precipitation followed by hydrothermal treatment using trisodium citrate, Tween 20, and polyethylene glycol (MW 600) as organic modifiers and starting from calcium nitrate and phosphoric acid. The particle sizes of the resultant hydroxyapatite nanorods varied with the chemical structures of the present organic modifiers and the crystallinity of the hydroxyapatite increased with an increasing autoclaving temperature.

Aqueous gold nanoparticles (Au-NPs) without surfactant protection undergo irreversible aggregation upon a cryogenic treatment. However, a cryogenic process on aqueous gold nanoparticle solution containing tannic acid did not lead to nanoparticle aggregation. The tannic acid serves as surfactant to prevent aggregation of gold nanoparticles. In contrast, a reduction in the particle size in this solution containing tannic acid was observed upon the cryogenic treatment with good reproducibility and uniformity.