Z. Abadi, S. M. Bidoki, V. Mottaghitalab, A. Benvidi, A. Shams-Nateri,
Volume 11, Issue 3 (september 2014)
Abstract
Silver nanoparticles are being given considerable attention because of their interesting properties and
potential applications. One such exploitable use is as the major constituent of conductive inks and pastes used for
printing various electronic components. This paper presents a novel direct-writing process for fabrication of the first
deposited silver nanoparticles (AgNPs) (50-200nm) electrode via a thermal inkjet printer. In this method, AgNPs were
chemically deposited by ejection of ascorbic acid and silver nitrate solutions onto different substrates such as paper
and textile fabrics. Silver deposited patterns were used as electrodes in different electrochemical experiments and their
morphology was also investigated in SEM observations. The highest conductivity of deposited electrodes obtained on
paper as the substrate was found to be around 5.54x105 S/m. Inkjet fabricated electrodes exhibited acceptable
electrochemical behavior in experiments designed for measuring the concentration of hydrogen peroxide as a
fundamental procedure for early determination of glucose. This novel inkjet silver deposition technique is introduced
to be considered as a promising method for ultimate single step fabrication of different electrochemical bio-sensors.
S. Alamolhoda, S. M. Mirkazemi, T. Shahjooyi, N. Benvidi,
Volume 13, Issue 1 (March 2016)
Abstract
Nano-sized NiFe2O4 powders were synthesized by sol–gel auto-combustion method using pH values from 7 to 9 in the sol. The effect of pH variations on complexing behavior of the species in the sol has been explained. Changes in phase constituents, microstructure and magnetic properties by changes in pH values were evaluated by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and vibration sample magnetometer (VSM) techniques. Changes in pH value from 7 to 9 changes the amounts of NiFe2O4, FeNi3 and α-Fe2O3 phases. Calculated mean crystallite sizes are in the range of 44 to 51nm. FESEM micrographs revealed that increasing the pH value to 9 causes formation of coarse particles with higher crystallinity. Saturation magnetization was increased from 36.96emu/g to 39.35emu/g by increasing pH value from 7 to 8 which is the result of increased FeNi3 content. Using higher pH values in the sol reduces the Ms value.
