Abstract A series of BUC-21/N-K2Ti4O9 composites (B1NX) were facilely fabricated from BUC-21 and N-K2Ti4O9 via ball-milling, and they were fully characterized using various techniques. The photocatalytic reduction of Cr(VI) over the B1NX composites was investigated systematically under various conditions, including different light sources, pH values, hole scavengers, and inorganic ions, in both real lake water and tap water. The BUC-21/N-K2Ti4O9 composites demonstrated remarkable photocatalytic Cr(VI) reduction performance, good reusability, and stability under both UV and white light irradiation. The introduction of N-K2Ti4O9 into BUC-21 not only broadened its light absorption region to white light, but also strongly inhibited the recombination of the photo-generated electrons and holes. Mechanisms of photocatalytic Cr(VI) reduction under both UV light and white light were proposed and verified by electrochemical measurements, active species capture experiments, and ESR measurements.

中文翻译：

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BUC-21/N-K2Ti4O9 复合材料上的光催化 Cr(VI) 消除：由于成分的微小差异导致性能的巨大差异

摘要 以 BUC-21 和 N-K2Ti4O9 为原料，通过球磨法制备了一系列 BUC-21/N-K2Ti4O9 复合材料 (B1NX)，并使用各种技术对其进行了充分表征。在各种条件下系统地研究了 B1NX 复合材料上 Cr(VI) 的光催化还原，包括不同的光源、pH 值、空穴清除剂和无机离子，在真实湖水和自来水中。BUC-21/N-K2Ti4O9 复合材料在紫外光和白光照射下均表现出显着的光催化 Cr(VI) 还原性能、良好的可重复使用性和稳定性。将 N-K2Ti4O9 引入 BUC-21 不仅将其光吸收范围扩大到白光，而且强烈抑制了光生电子和空穴的复合。