Synthesis of sub-micron 2SnO·(H2O) powders by chemical reduction process was performed at room temperature as function of viscosity of methanol solution and molecular weight of PVP (polyvinylpyrrolidone). Tin(II) 2-ethylhexanoate and sodium borohydride were used as the tin precursor and the reducing agent, respectively. Simultaneous calcination and sintering processes were additionally performed by heating the 2SnO·(H2O) powders. In the synthesis of the 2SnO·(H2O) powders, it was possible to control the powder size using different combinations of the methanol solution viscosity and the PVP molecular weight. The molecular weight of PVP particularly influenced the size of the synthesized 2SnO·(H2O) powders. A holding time of 1 hr in air at 500˚C sufficiently transformed the 2SnO·(H2O) into SnO2 phase; however, most of the PVP (molecular weight: 1,300,000) surface-capped powders decomposed and was removed after heating for 1 h at 700˚C. Hence, heating for 1 h at 500˚C made a porous SnO2 film containing residual PVP, whereas dense SnO2 films with no significant amount of PVP formed after heating for 1 h at 700˚C.

FePt nanoparticles for high-density magnetic recording media were synthesized by the simultaneous chemical reduction of Fe(acac) and Pt(acac) with 1,2-hexadecanediol as the reducing reagent. TEM images showed that the shape of as-synthesized FePt nanoparticle was spherical and average particle size was 3 nm. Also, SAD pattern showed that crystal structure was disordered FCC (face centered cubic). These FCC structured nanoparticles were transformed FCT (face centered tetragonal) structure by annealing at 55 for 30 min in Ar atmosphere. XRD analysis revealed that as-synthesized FePt nanoparticles were transformed from disordered FCC to ordered FCT. Finally, the coercivity of 2 kOe for FePt nanoparticles with FCT structure was obtained by VSM measurement.