| Influence of Metal Oxide Nanoparticles Concentration on their Zeta Potential | |
|---|---|
| 學年 | 102 |
| 學期 | 1 |
| 出版（發表）日期 | 2013-10-01 |
| 作品名稱 | Influence of Metal Oxide Nanoparticles Concentration on their Zeta Potential |
| 作品名稱（其他語言） | |
| 著者 | Wang, Nan; Hsu, Chien; Zhu, Lihua; Tseng, Shiojenn; Hsu, Jyh-Ping |
| 單位 | 淡江大學數學學系 |
| 出版者 | Maryland Heights: Academic Press |
| 著錄名稱、卷期、頁數 | Journal of Colloid and Interface Science 407, pp.22-28 |
| 摘要 | In an attempt to estimate the zeta potential of various metal oxide nanoparticles (NPs) dispersed in water, it is interesting to observe that both the magnitude and the sign of this property depend highly upon their concentration. For example, in the case of naked TiO2 at pH 6, the zeta potential increased from -6.7 to 8.2 mV as the particle concentration varied from 0.5 to 5 mg L(-1). As a result, the isoelectric points of naked TiO2, Fe3O4, Fe(OH)3, and Al2O3-coated TiO2 could deviate ca. one, one, two, and three pH units, respectively, depending upon the particle concentration. We showed that these behaviors arise mainly from that the dissolved ambient CO2 reacts with the particle surface functional groups to form M-OCO2(-), which neutralizes or even overcompensates the particle surface charge. The surface density of M-OCO2(-), [M-OCO2(-)](s) depends upon the particle concentration; if it is sufficiently high, [M-OCO2(-)](s) becomes negligible, so is its influence on the zeta potential. We concluded that the zeta potential measurements for the tested NPs are reliable only if their concentration exceeds a certain level. This also applies to other metal oxides or hydroxides, the surface of which reacts appreciably with dissolved CO2. The results gathered are of practical significance in estimating the surface properties of unknown and/or newly synthesized NPs since conventional measurements are usually made at dilute particle concentrations. |
| 關鍵字 | Zeta potential; Surface charge; Particle concentration; Dissolved CO2 |
| 語言 | en |
| ISSN | 0021-9797 1095-7103 |
| 期刊性質 | 國外 |
| 收錄於 | SCI |
| 產學合作 | |
| 通訊作者 | |
| 審稿制度 | 是 |
| 國別 | USA |
| 公開徵稿 | |
| 出版型式 | 紙本 電子版 |
| 相關連結 |
機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/97842 ) |
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