Tian Lei, Föhlinger Jens, Pati Palas Baran, Zhang Zhibin, Lin Junzhong, Yang Wenxing, Johansson Malin, Kubart Tomas, Sun Junliang, Boschloo Gerrit, Hammarström Leif, Tian Haining
Department of Chemistry-Ångström Laboratories, Uppsala University, Box 523, SE75120 Uppsala, Sweden.
Phys Chem Chem Phys. 2017 Dec 20;20(1):36-40. doi: 10.1039/c7cp07088h.
In this study, a core-shell NiO-dye-TiO mesoporous film was fabricated for the first time, utilizing atomic layer deposition technique and a newly designed triphenylamine dye. The structure of the film was confirmed by SEM, TEM, and EDX. Excitation of the dye led to efficient and fast charge separation, by hole injection into NiO, followed by an unprecedentedly fast dye regeneration (t ≤ 500 fs) by electron transfer to TiO. The resulting charge separated state showed a pronounced transient absorption spectrum caused by the Stark effect, and no significant decay was found within 1.9 ns. This indicates that charge recombination between NiO and TiO is much slower than that between the NiO and the reduced dye in the absence of the TiO layer (t ≈ 100 ps).
在本研究中，首次利用原子层沉积技术和新设计的三苯胺染料制备了核壳结构的NiO-染料-TiO介孔薄膜。通过扫描电子显微镜（SEM）、透射电子显微镜（TEM）和能谱仪（EDX）对薄膜结构进行了确认。染料的激发导致了高效且快速的电荷分离，通过空穴注入到NiO中，随后通过电子转移到TiO实现了前所未有的快速染料再生（t≤500飞秒）。所产生的电荷分离态呈现出由斯塔克效应引起的明显瞬态吸收光谱，并且在1.9纳秒内未发现明显衰减。这表明在没有TiO层的情况下，NiO与TiO之间的电荷复合比NiO与还原染料之间的电荷复合要慢得多（t≈100皮秒）。
