Without light at night, the system for photocatalytic degradation of refractory organic pollutants in aquatic environments based on free radicals will fall into a dormant state. Hence, a round-the-clock photocatalyst (CCN@SMSED) was prepared by in situ growth of cyanide-deficient g-CN on the surface of SrMgSiO:Eu,Dy through a simple calcination method. The CCN@SMSED exhibits an outstanding oxidative degradation ability for refractory tetracycline (TC) in water under both light and dark conditions, which is attributed to the synergistic effect of free radical (•O and •OH) and non-radical (h and O). Electrochemical analyses further indicate that direct electron transfer (DET) is also one of the reasons for the efficient degradation of TC. Remarkably, the continuous working time of the round-the-clock photocatalyst in a dark environment was estimated for the first time (about 2.5 h in this system). The degradation pathways of TC mainly include demethylation, ring opening, deamination and dehydration, and the growth of shows that the process is biosafe. More importantly, CCN@SMSED holds significant promise for practical application due to its low energy consumption and suitability for removing TC from a variety of complex water bodies. This work provides an energy consumption reference for the practical application of round-the-clock photocatalytic degradation of organic pollutants.

中文翻译：

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缺氰g-C3N4全天候光催化降解四环素：机理及应用前景评估


夜间没有光照，基于自由基的光催化降解水生环境中难降解有机污染物的系统就会陷入休眠状态。因此，通过简单的煅烧方法，在SrMgSiO:Eu,Dy表面原位生长缺氰的g-CN，制备了全天候光催化剂（CCN@SMSED）。 CCN@SMSED在光和暗条件下对水中难降解的四环素（TC）表现出出色的氧化降解能力，这归因于自由基（·O和·OH）和非自由基（h和O）的协同作用）。电化学分析进一步表明直接电子转移（DET）也是TC高效降解的原因之一。值得注意的是，首次估算了全天候光催化剂在黑暗环境下的连续工作时间（该系统约为2.5小时）。 TC的降解途径主要包括去甲基化、开环、脱氨基和脱水等，其增长表明该过程是生物安全的。更重要的是，CCN@SMSED 由于其低能耗且适合从各种复杂水体中去除 TC，因此在实际应用中具有重大前景。该工作为全天候光催化降解有机污染物的实际应用提供了能耗参考。