Bismuth oxide (Bi_xO_y), an important bismuth-based semiconductor with visible-light response, good structural stability and non-toxicity, has been identified as a potential candidate for chromium (Cr(VI))-containing wastewater remediation. However, the poor broadband light response and easy electron–hole recombination generally lead to unfavorable catalytic activity. Constructing a heterostructure is demonstrated to be an effective strategy for improving the catalytic performance of Bi_xO_y-based photocatalysts due to the improved photoresponse and promoted interfacial carrier mobility. Herein, CdS nanoparticles with low work function and good visible-light response were chosen as the cocatalyst to construct the p–n type Bi_xO_y/CdS heterostructure via a solvothermal method. Due to the formation of typical II-type induced mechanism, the interfacial carrier mobility and broadband light response were effectively improved; thereby, remarkably enhanced simulated solar-light (SSL)-induced aqueous Cr(VI) reduction activity (0.1265 min⁻¹) was achieved by the optimum Bi_xO_y/CdS catalyst in the absence of scavengers, which is ∼34.2-fold greater than pristine Bi_xO_y (3.7 × 10⁻³ min⁻¹) and possesses distinct advantage compared with previous reports. Also, the promoted carrier transfer effectively suppresses photocorrosion of the CdS microstructure, resulting in a desirable photostability under long-term photoinduction. This study provides a feasible strategy for aqueous Cr(VI) pollution remediation.

中文翻译：

---

模拟太阳光诱导下 BixOy/CdS 异质结构快速修复 Cr(VI) 废水

氧化铋 (Bi _x O _y ) 是一种重要的铋基半导体，具有可见光响应、良好的结构稳定性和无毒性，已被确定为含铬 (Cr( VI )) 废水修复的潜在候选者。然而，较差的宽带光响应和容易的电子-空穴复合通常导致不利的催化活性。构建异质结构被证明是提高 Bi _x O _y催化性能的有效策略基于改进的光响应和促进界面载流子迁移率的光催化剂。在此，选择具有低功函数和良好可见光响应的 CdS 纳米粒子作为助催化剂，通过溶剂热法构建 p-n 型 Bi _x O _y /CdS 异质结构。由于形成了典型的II型诱导机制，有效提高了界面载流子迁移率和宽带光响应；因此，通过最佳 Bi _x O _y实现了显着增强的模拟太阳光 (SSL) 诱导的水性 Cr( VI ) 还原活性 (0.1265 min ^-1 )/CdS 催化剂在没有清除剂的情况下，比原始 Bi _x O _y (3.7 × 10 ^-3 min ^-1 )大~34.2 倍，并且与之前的报道相比具有明显的优势。此外，促进的载流子转移有效地抑制了 CdS 微结构的光腐蚀，从而在长期光诱导下获得了理想的光稳定性。该研究为水体Cr( VI )污染修复提供了一种可行的策略。