Water pollution and the energy demand are calling for sustainable technologies such as photocatalysis, yet actual methods are difficult to upscale due to the poor recovery and reusability of nanocatalysts. This issue could be solved by using photocatalytic sponges, which display high surface area and reusability. Here we review the applications of photocatalytic sponges for wastewater degradation, disinfection, carbon dioxide reduction, and hydrogen production. Photocatalytic sponges are fabricated by templating, dip coating, sol–gel, polymerization, electrospinning, and freeze drying. Remarkable results include the monolithic microreactor with Ag/AgCl coated on a polydopamine-modified melamine sponge, which exhibits a 100% methylene blue degradation in 15 min, with a reusability of five cycles. An hydrogen production rate of 11.33 mmol h⁻¹ g⁻¹ was obtained with the pyridazine-doped graphitic carbon nitride with nitrogen defects and a spongy structure.

水污染和能源需求需要光催化等可持续技术，但由于纳米催化剂的回收和可重复使用性较差，实际方法很难升级。这个问题可以通过使用光催化海绵来解决，它具有高表面积和可重复使用性。在这里，我们回顾了光催化海绵在废水降解、消毒、二氧化碳还原和制氢方面的应用。光催化海绵通过模板、浸涂、溶胶-凝胶、聚合、静电纺丝和冷冻干燥制造。显着的结果包括在聚多巴胺改性三聚氰胺海绵上涂覆 Ag/AgCl 的整体式微反应器，其在 15 分钟内表现出 100% 亚甲蓝降解，并且可重复使用五个周期。利用具有氮缺陷和海绵结构的哒嗪掺杂石墨碳氮化物获得了11.33mmol h ^-1  g ^-1的氢气产率。