Hubei Key Laboratory of Mineral Resources Processing and Environment, State Key Laboratory of Silicate Materials for Architectures , Wuhan University of Technology , 122 Luoshi Road , Wuhan 430070 , China.
ACS Appl Mater Interfaces. 2019 Feb 20;11(7):7112-7122. doi: 10.1021/acsami.8b21693. Epub 2019 Feb 6.
Deliberate tuning of nanoparticles encapsulated with nanosheet shells can bring about fascinating photocatalytic properties because of the fast charge-transfer characteristics of a nanosized core-shell structure. Herein, a novel core-shell-structured BiO/BiO composite was fabricated through a one-step hydrothermal method. The core-shell BiO/BiO composite presented distinct optical absorption property, including UV, visible, and near-infrared (NIR) light regions. Compared to BiO and BiO, the BiO/BiO composite revealed improved broad spectrum light-responsive molecular oxygen activation into O, especially achieving O generation under NIR light irradiation. The achievement that enhanced broad spectrum light-activated molecular oxygen activation could be ascribed to the faster electron transfer confirmed by the electron spin resonance (ESR) spectra, photoluminescence (PL) spectra, photoelectrochemical test, and quantitative analysis of O. The strong interface effect of the BiO/BiO composite was confirmed by X-ray photoelectron spectroscopy analysis. Density functional theory calculated results suggested that the BiO/BiO composite revealed increased density of states near the Fermi level, suggesting that it possessed higher carrier mobility as compared to BiO and BiO, contributing to the faster separation of photoinduced carriers and the generation of O. Benefiting to the heterojunction, the BiO/BiO composite showed improved photocatalytic activity and anti-photocorrosion activity during rhodamine B (RhB) and ciprofloxacin (CIP) degradation with the irradiation of UV, visible, and NIR lights. Besides, the possible photocatalytic mechanism and transformation pathway of RhB and CIP degradation by the BiO/BiO composite were proposed by the analyses of the liquid chromatography-mass spectrometry. This study furnishes a new strategy for fabricating high-efficient and broad spectrum light-driven heterojunction photocatalysts for environment purification.
通过一步水热法制备了一种新型的核壳结构 BiO/BiO 复合材料。核壳 BiO/BiO 复合材料具有独特的光学吸收特性，包括紫外、可见和近红外（NIR）光区。与 BiO 和 BiO 相比，BiO/BiO 复合材料表现出了改善的宽光谱光响应分子氧活化为 O 的性能，特别是在近红外光照射下能够产生 O。增强的宽光谱光激活分子氧活化能力归因于更快的电子转移，这一结论得到了电子自旋共振（ESR）谱、光致发光（PL）谱、光电化学测试和 O 定量分析的证实。X 射线光电子能谱分析证实了 BiO/BiO 复合材料具有较强的界面效应。密度泛函理论计算结果表明，BiO/BiO 复合材料在费米能级附近的态密度增加，表明其载流子迁移率高于 BiO 和 BiO，有助于光致载流子的快速分离和 O 的生成。得益于异质结，BiO/BiO 复合材料在 RhB 和 CIP 降解过程中，在紫外、可见和近红外光照射下表现出了提高的光催化活性和抗光腐蚀性。此外，通过液相色谱-质谱分析提出了 BiO/BiO 复合材料降解 RhB 和 CIP 的可能光催化机制和转化途径。本研究为制备高效宽光谱光驱动异质结光催化剂用于环境净化提供了一种新策略。
