【摘要】 界面电荷转移（CT）在提高染料敏化太阳能电池（DSSCs）的光电转换效率中起重要作用，但一直未被充分探索。在这里，构建了TiO₂@N719@Ag DSSCs体系，并通过表面增强拉曼散射（SERS）光谱监测了CT过程。同时，作为最常见的外部刺激之一，高压会增加TiO₂ NPs的自由载流子密度并导致带隙变窄。在高压SERS实验中，观察到N719染料在TiO₂@N719@Ag体系中显着增强至压力达到2.48 GPa,这与电荷转移度(ρ_CT)的变化趋势一致。表明带隙变化会强烈影响CT过程，进一步影响SERS信号强度(或ρ_CT),从而增加DSSCs的CT概率。最后，为了更清楚地观察DSSCs的CT过程，提出了描述CT机制的模型。SERS光谱有望成为探索DSSCs设备中界面CT行为的一种有前途的技术，这可能会进一步拓宽提高电池效率的思路。更多还原

【Abstract】 The interfacial charge transfer（CT） that plays an important role in enhancing the photoelectric conversion efficiency of dye-sensitized solar cells（DSSCs） has not always been fully explored. Here, TiO₂@N719@Ag DSSCs system was constructed, and the CT processes have been monitored by surface-enhanced Raman scattering（SERS） spectra. Meanwhile, it is well known that as one of the most common external stimulis, high pressure can increase the free carrier density of TiO₂ NPs and cause the band gap to narrow. In the high pressure SERS experiment, we observed a significant enhancement of N719 dye in the TiO₂@N719@Ag system up to 2.48 GPa, which is consistent with the variation trend of charge transfer degree(ρ_CT). It is indicated that band gap changes will strongly affect the CT process, further influence the SERS signal intensity(or ρ_CT), and thus increase the CT probability of DSSCs. Finally, in order to observe the CT process of DSSCs more clearly, the models describing the CT mechanism have been proposed. SERS spectroscopy is expected to be a promising technique for the exploration of the interfacial CT behavior in DSSCs devices, which may further broaden the thoughts of improvement of efficiency of cells.更多还原