In this study, the relaxation dynamics of photoexcitations in anatase TiO₂ nanoparticles (NPs) and their composites with metal (Au), non-metal (carbon nanotube CNT, graphene G) and combination of them (CNT-Au, G-Au) as well as its implications on the photocatalytic activities are presented. The peak positions for the steady-state photoluminescence observed at about 3 eV are invariant while the defects-related emission at visible region is blue-shifted, which depends on the nature of foreign material in the composites. Using ps time-resolved photoluminescence measurement, the decay time constants for these photoexcitations decreased with forming the composites. Concretely, the charge transfer time in TiO₂ NPs is about 35.8 ps, which is longer than that in its composites, in the range of 9.7–28.7 ps. Their Raman spectra supported the plausible photodynamics of TiO₂ nanocomposites that is proposed to describe the participation of photoexcitations in the photocatalytic reaction through charge separation between the different nanomaterials.

在这项研究中，锐钛矿型TiO ₂纳米颗粒（NPs）及其与金属（Au），非金属（碳纳米管CNT，石墨烯G）及其组合（CNT-Au，G-Au）的复合材料中光激发的弛豫动力学以及其对光催化活性的影响。在约3 eV处观察到的稳态光致发光的峰值位置是不变的，而与缺陷相关的可见光区域的发射呈蓝移，这取决于复合材料中异物的性质。使用ps时间分辨的光致发光测量，随着形成复合材料，这些光激发的衰减时间常数减小。具体而言，TiO _2中的电荷转移时间NP约为35.8 ps，比其复合材料更长，在9.7-28.7 ps的范围内。他们的拉曼光谱证明了TiO ₂纳米复合材料的合理的光动力学，该动力学被认为是通过不同纳米材料之间的电荷分离来描述光激发参与光催化反应的过程。