Contribution of multiple reflections to light utilization efficiency of submicron hollow TiO2 photocatalyst

In this work, we carried out both theoretical calculation and experimental studies to reveal the contribution of hollow geometry to the light utilization efficiency of the TiO2 photocatalysts in diluted aqueous solution. It is found that the single or multi-shelled hollow structures do not induce significant multiple reflections within the shells as widely believed in previous reports, and therefore the geometric factor has minimal contribution to the improvement of the light utilization efficiency of the photocatalyst. To design TiO2 photocatalysts with higher activity, it is more appropriate to focus on the improvement of the crystallinity, diffusion, surface area, and dispersity of the catalysts, rather than their geometric shapes.