• • The paper emphasizes a paradigm shift from intrinsic activity to surface serviceability, noting that high intrinsic activity alone does not guarantee stable performance; coating performance is determined by coupled factors such as interfacial adhesion, film structure, and environmental aging, which are critical for industrial deployment.
• • Current challenges include long-term deactivation, coating-substrate interfacial stability, trade-offs among multiple functions, adequacy of evaluation methods, and scalability of fabrication, forming a progressive service chain that must be addressed for practical applications.
• • The perspective calls for establishing service-relevant evaluation protocols and developing scalable and repairable fabrication routes, which are essential for moving photocatalytic coatings from laboratory materials to engineering surfaces.
• • The work is funded by the National Natural Science Foundation of China (22309046) and Collaborative Innovation Achievement Project of Heilongjiang Province Double First-Class Disciplines (LJGXCG2024-F12, LJGXCG2023-085), indicating institutional support for advancing this research direction.