Chinese Education Ministry Key Laboratory of Resource Chemistry, Shanghai Normal University , Shanghai 200234, China.
Department of Chemistry, University of Florida , Gainesville, Florida 32611, United States.
ACS Appl Mater Interfaces. 2017 May 24;9(20):16959-16966. doi: 10.1021/acsami.6b11494. Epub 2017 May 15.
Pt-doped mesoporous Ti self-doped TiO (Pt-Ti/TiO) is in situ synthesized via an ionothermal route, by treating metallic Ti in an ionic liquid containing LiOAc, HOAc, and a HPtCl aqueous solution under mild ionothermal conditions. Such Ti-enriched environment, as well as oxygen vacancies, is proven to be effective for allowing the in situ reduction of Pt ions uniformly located in the framework of the TiO bulk. The photocatalytic H evolution of Pt-Ti/TiO is significantly higher than that of the photoreduced Pt loaded on the original TiO and commercial P25. Such greatly enhanced activity is due to the various valence states of Pt (Pt, n = 0, 2, or 3), forming Pt-O bonds embedded in the framework of TiO and ultrafine Pt metal nanoparticles on the surface of TiO. Such Pt-O bonds could act as the bridges for facilitating the photogenerated electron transfer from the bulk to the surface of TiO with a higher electron carrier density (3.11 × 10 cm), about 2.5 times that (1.25 × 10 cm) of the photoreduced Pt-Ti/TiO sample. Thus, more photogenerated electrons could reach the Pt metal for reducing protons to H.
Pt 掺杂介孔 Ti 自掺杂 TiO（Pt-Ti/TiO）通过离子热途径原位合成，即将金属 Ti 在含有 LiOAc、HOAc 和 HPtCl 水溶液的离子液体中在温和的离子热条件下处理。这种富 Ti 环境以及氧空位被证明可有效地允许 Pt 离子均匀地位于 TiO 体相的骨架中进行原位还原。Pt-Ti/TiO 的光催化 H 2 析出活性显著高于原始 TiO 负载的光还原 Pt 和商业 P25 的活性。这种活性的极大提高归因于 Pt 的各种价态（Pt，n = 0、2 或 3），形成嵌入 TiO 骨架中的 Pt-O 键和 TiO 表面上的超细 Pt 金属纳米颗粒。这些 Pt-O 键可以充当桥梁，促进具有更高电子载流子密度（3.11×10^18 cm^-3，约为光还原 Pt-Ti/TiO 样品的 2.5 倍）的 TiO 体相到表面的光生电子转移。因此，更多的光生电子可以到达 Pt 金属，用于将质子还原为 H。
