Department of Chemistry and Biochemistry, Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, AZ 85287, USA.
Nanotechnology. 2009 Dec 16;20(50):505203. doi: 10.1088/0957-4484/20/50/505203. Epub 2009 Nov 19.
A triethanolamine-protected silane, 1-(3'-amino)propylsilatrane, was incorporated into the structure of porphyrin- and ruthenium-based dyes and used to link them to transparent semiconductor nanoparticulate metal oxide films. Silatrane reacts with the metal oxide to form strong, covalent silyl ether bonds. In this study, silatrane-functionalized dyes and analogous carboxylate-functionalized dyes were used as visible light sensitizers for porous nanoparticulate SnO(2) photoanodes. The performance of the dyes was compared in photoelectrochemical cells incorporating either non-regenerative or regenerative redox components. The non-regenerative cell used NADH (beta-nicotinamide adenine dinucleotide) as a sacrificial electron donor and Hg(2)SO(4)/Hg as a sacrificial cathode, whereas the regenerative cell used the iodide/triiodide redox couple. Experiments showed that the silyl ether bonding gave the electrodes increased stability toward sensitizer desorption compared to carboxylate surface linkages. Porphyrin-silatrane dyes also demonstrated similar or better performance than their carboxylate analogs in photoelectrochemical cells. The improvement correlates with the results from transient absorbance spectroscopy, which show that the longer linker on the silatrane porphyrins slows charge recombination between oxidized porphyrin and the electrode surface. The improved photoelectrochemical cell efficiency and stability of the silatrane-based dyes compared to carboxylates demonstrate that silatranes are promising agents for bonding organic molecules to metal oxide surfaces.
三乙醇胺保护的硅烷 1-(3'-氨基)丙基硅氮烷被掺入卟啉和钌基染料的结构中，并用于将它们连接到透明半导体纳米颗粒金属氧化物薄膜上。硅氮烷与金属氧化物反应形成强的、共价的硅醚键。在这项研究中，硅氮烷功能化染料和类似的羧酸盐功能化染料被用作多孔纳米颗粒 SnO2 光阳极的可见光敏化剂。在包含非再生或再生氧化还原组分的光电化学电池中比较了染料的性能。非再生电池使用 NADH（β-烟酰胺腺嘌呤二核苷酸）作为牺牲电子供体，Hg（2）SO4/Hg 作为牺牲阴极，而再生电池使用碘化物/三碘化物氧化还原对。实验表明，与羧酸盐表面键合相比，硅醚键合赋予电极对敏化剂解吸更高的稳定性。硅氮烷卟啉染料在光电化学电池中的性能也与它们的羧酸盐类似物相似或更好。这种改进与瞬态吸收光谱的结果相关，表明硅氮烷卟啉上更长的连接物减缓了氧化卟啉和电极表面之间的电荷复合。与羧酸盐相比，硅氮烷基染料的光电化学电池效率和稳定性的提高表明，硅氮烷是将有机分子键合到金属氧化物表面的有前途的试剂。
