Department of Applied Chemistry, School of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashi-Osaka, Osaka 577-8502, Japan.
Langmuir. 2011 Jun 7;27(11):7294-300. doi: 10.1021/la200587s. Epub 2011 May 9.
UV light irradiation of TiO(2) (λ > 320 nm) in a mixed solution of AgNO(3) and S(8) has led to the formation of Ag(2)S quantum dots (QDs) on TiO(2), while Ag nanoparticles (NPs) are photodeposited without S(8). Photoelectrochemical measurements indicated that the Ag(2)S photodeposition proceeds via the preferential reduction of Ag(+) ions to Ag(0), followed by the chemical reaction with S(8). The application of this in situ photodeposition technique to mesoporous (mp) TiO(2) nanocrystalline films coated on fluorine-doped SnO(2) (FTO) electrodes enables formation of Ag(2)S QDs (Ag(2)S/mp-TiO(2)/FTO). Ag(2)S/mp-TiO(2)/FTO has the interband transition absorption in the whole visible region, while in the spectrum of Ag/mp-TiO(2)/FTO, a localized surface plasmon resonance absorption of Ag NPs is present centered at 490 nm. Ag(2)S QD-sensitized photoelectrochemical cells using the Ag(2)S/mp-TiO(2)/FTO and Ag/mp-TiO(2)/FTO photoanodes were fabricated. Under illumination of one sun, the Ag(2)S photoanode cell yielded H(2) at a rate of 0.8 mL·h(-1) with a total conversion efficiency of 0.29%, whereas the Ag/mp-TiO(2)/FTO photoanode is inactive.
紫外光辐照 TiO(2)（λ > 320nm）在 AgNO(3)和 S(8)的混合溶液中导致 Ag(2)S 量子点（QD）在 TiO(2)上形成，而没有 S(8)时则会光沉积出 Ag 纳米颗粒（NPs）。光电化学测量表明，Ag(2)S 的光沉积是通过优先还原 Ag(+)离子到 Ag(0)，然后与 S(8)进行化学反应进行的。将这种原位光沉积技术应用于涂覆在掺氟氧化锡（FTO）电极上的介孔（mp）TiO(2)纳米晶薄膜，可形成 Ag(2)S QD（Ag(2)S/mp-TiO(2)/FTO）。Ag(2)S/mp-TiO(2)/FTO 在整个可见光区域具有带间跃迁吸收，而在 Ag/mp-TiO(2)/FTO 的光谱中，存在以 490nm 为中心的 Ag NPs 的局域表面等离子体共振吸收。使用 Ag(2)S/mp-TiO(2)/FTO 和 Ag/mp-TiO(2)/FTO 光阳极制备了 Ag(2)S QD 敏化光电化学电池。在阳光照射下，Ag(2)S 光阳极电池以 0.8mL·h(-1)的速率产生 H(2)，总转换效率为 0.29%，而 Ag/mp-TiO(2)/FTO 光阳极则没有活性。
