High photon conversion efficiencies and low-cost materials are crucial for implementing photocatalytic solutions in large scale applications. To improve the conversion efficiencies, knowledge on the lifetime and dynamics of photogenerated charge carriers is fundamental, for which transient absorption spectroscopy has provided important insights. Regarding the cost of the materials, one approach to decrease it is mixing the photocatalyst with cheaper additives while avoiding a significant loss in its activity. In this short review we summarize the findings of our group dealing with both aspects. A new model to fit transient absorption decays, based on fractal kinetics, is discussed. The model has been applied to the transient decays of TiO₂ mixtures with binary particle size distributions and of TiO₂ mixtures with a priori inert additives. In both cases, the insights obtained from the model were crucial to explain the photocatalytic activities of the mixtures.

高光子转换效率和低成本材料对于在大规模应用中实施光催化解决方案至关重要。为了提高转换效率，关于光生电荷载流子的寿命和动力学的知识是基础，瞬态吸收光谱法提供了重要的见解。关于材料的成本，降低其成本的一种方法是将光催化剂与较便宜的添加剂混合，同时避免其活性显着损失。在这篇简短的评论中，我们总结了我们小组在两个方面的发现。基于分形动力学，讨论了一种适合瞬态吸收衰减的新模型。该模型已应用于具有二元粒径分布的TiO ₂混合物和TiO的瞬态衰减_2种与先验惰性添加剂的混合物。在两种情况下，从模型中获得的见解对于解释混合物的光催化活性至关重要。