“…In macro aspect, the thin liquid film PC reactor can effectively reduce light loss caused by solution absorption [6,7]. To further change the planar substrate to wedge or pyramid structures can not only enlarge PC surface area, but also enhance light utilization efficiency due to multiple reflection of incident light [8,9]. In micro aspect, photocatalysts with light-harvesting morphologies such as flower-like structure [10], hollow sphere [11] and core-shell structure [12] have also been synthesized, among which, bismuth oxyhalides (BiOX; X = Cl, Br) have attracted intensive attention in recent years because of their high PC activity and layered crystal structure [13][14][15].…”