Department of Chemical Engineering, National Cheng Kung University, Tainan, 701, Taiwan.
Nanoscale Res Lett. 2013 Feb 5;8(1):57. doi: 10.1186/1556-276X-8-57.
Cs0.33WO3 nanoparticles have been prepared successfully by a stirred bead milling process. By grinding micro-sized coarse powder with grinding beads of 50 μm in diameter, the mean hydrodynamic diameter of Cs0.33WO3 powder could be reduced to about 50 nm in 3 h, and a stable aqueous dispersion could be obtained at pH 8 via electrostatic repulsion mechanism. After grinding, the resulting Cs0.33WO3 nanoparticles retained the hexagonal structure and had no significant contaminants from grinding beads. Furthermore, they exhibited a strong characteristic absorption and an excellent photothermal conversion property in the near-infrared (NIR) region, owing to the free electrons or polarons. Also, the NIR absorption and photothermal conversion property became more significant with decreasing particle size or increasing particle concentration. When the concentration of Cs0.33WO3 nanoparticles was 0.08 wt.%, the solution temperature had a significant increase of above 30°C in 10 min under NIR irradiation (808 nm, 2.47 W/cm2). In addition, they had a photothermal conversion efficiency of about 73% and possessed excellent photothermal stability. Such an effective NIR absorption and photothermal conversion nanomaterial not only was useful in the NIR shielding, but also might find great potential in biomedical application.
通过搅拌珠磨工艺成功制备了 Cs0.33WO3 纳米粒子。通过用 50μm 直径的研磨珠研磨微尺寸的粗粉末，在 3 小时内 Cs0.33WO3 粉末的平均水动力直径可减小至约 50nm，并通过静电排斥机制在 pH8 下获得稳定的水基分散体。研磨后，所得 Cs0.33WO3 纳米粒子保留了六方结构，并且没有来自研磨珠的明显污染物。此外，由于自由电子或极化子，它们在近红外（NIR）区域表现出强的特征吸收和优异的光热转换性能。另外，随着粒径的减小或颗粒浓度的增加，NIR 吸收和光热转换性能变得更加显著。当 Cs0.33WO3 纳米粒子的浓度为 0.08wt.%时，在 NIR 照射（808nm，2.47W/cm2）下 10 分钟内溶液温度有超过 30°C 的显著升高。此外，它们具有约 73%的光热转换效率和优异的光热稳定性。这种有效的 NIR 吸收和光热转换纳米材料不仅在 NIR 屏蔽方面有用，而且在生物医学应用中可能具有很大的潜力。
