Construction of novel phosphonate-based MOF/P–TiO2 heterojunction photocatalysts: enhanced photocatalytic performance and mechanistic insight,Environmental Science: Nano

当前位置： X-MOL 学术 › Environ. Sci.: Nano › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Construction of novel phosphonate-based MOF/P–TiO2 heterojunction photocatalysts: enhanced photocatalytic performance and mechanistic insight
Environmental Science: Nano ( IF 5.8 ) Pub Date : 2020/01/06 , DOI: 10.1039/c9en01180c
Tianyu Zeng _{1,

2,

3,

4} , Dajun Shi _{4,

5,

6} , Qingrong Cheng _{1,

2,

3,

4} , Guiying Liao _{4,

7,

8,

9} , Hong Zhou _{1,

2,

3,

4} , Zhiquan Pan _{1,

2,

3,

4}

Affiliation

Development of highly efficient photocatalysts for photocatalysis research has been a hot research area in recent years. Herein, the phosphate-based metal organic framework (MOF)/P–TiO₂ hybrid composites (MOF_x/P–TiO₂) were first synthesized using the phosphonate-based MOF [Cd(H₂L)]_n (H₄L = 2,5-dimethylbenzene-1,4-diylbis(methylene)diphosphonic acid) and phosphated mesoporous TiO₂ beads (P–TiO₂) using a versatile step-by-step self-assembly strategy for environmental remediation. The results showed that the Cd-MOF loading content in the MOF_x/P–TiO₂ has an important influence on the degradation of pollutants, and the hybrid materials could significantly enhance the photocatalytic activity for the photo-oxidative degradation of RhB (97.6% in 25 min over MOF_1.5/P–TiO₂) and the reduction of Cr(VI) (96.1% in 60 min over MOF_0.5/P–TiO₂) in comparison with the single-component Cd-MOF or P–TiO₂. The enhancement of the photocatalytic activity of MOF_x/P–TiO₂ could be mainly attributed to: (i) the strong light absorption capacity, and (ii) the effective photogenerated charge separation and transfer through the coupled heterojunction interfaces of P–TiO₂ and Cd-MOF. Furthermore, the results verified that the matched band structure of P–TiO₂ and Cd-MOF could induce a superfast Z-scheme interfacial charge transfer path. Therefore, a reasonable Z-scheme charge transfer mechanism was proposed based on the active species trapping experiments and the results of electron spin resonance (ESR). More importantly, MOF_0.5/P–TiO₂ and MOF_1.0/P–TiO₂ possess a good stability and reusability after recycling five times owing to the high chemical stability of the Cd-MOF, P–TiO₂ and heterojunctions. The present work provides a promising approach to construct direct Z-scheme porous heterojunctions for elimination of environmental pollutants.

中文翻译：

新型基于膦酸酯的MOF / P–TiO2异质结光催化剂的构建：增强的光催化性能和机理研究

近年来，用于光催化研究的高效光催化剂的开发一直是研究的热点。在此，首先使用基于膦酸酯的MOF [Cd（H ₂ L）] _n（H ₄ L ）合成了基于磷酸盐的金属有机骨架（MOF）/ P-TiO ₂杂化复合物（MOF _x / P-TiO ₂）。= 2,5-二甲基苯-1,4-二基双（亚甲基）二膦酸）和磷酸盐化的介孔TiO ₂珠（P–TiO ₂），采用了一种多功能的逐步自组装策略进行环境修复。结果表明，MOF _x / P–TiO _2中Cd-MOF的负载量对污染物的降解具有重要影响，杂化材料可以显着增强光催化活性，从而使RhB的光氧化降解（在25分钟内超过MOF _1.5 / P-TiO ₂达到97.6％）和Cr（VI）（与单组分Cd-MOF或P-TiO ₂相比，在60分钟内超过MOF _0.5 / P-TiO _2的96.1％）。MOF _x / P-TiO ₂的光催化活性增强主要归因于：（i）强大的光吸收能力，以及（ii）有效的光生电荷分离和通过P-TiO ₂的耦合异质结界面转移和Cd-MOF。此外，结果证实了P–TiO ₂和Cd-MOF的匹配能带结构可以诱导Z型界面电荷转移的超快路径。因此，基于活性物质的俘获实验和电子自旋共振（ESR）的结果，提出了合理的Z-方案电荷转移机制。更重要的是，由于Cd-MOF，P-TiO ₂和异质结的高化学稳定性，MOF _0.5 / P-TiO ₂和MOF _1.0 / P-TiO ₂在循环五次后具有良好的稳定性和可重复使用性。目前的工作为构建直接Z提供了一种有前途的方法方案的多孔异质结，可消除环境污染物。

更新日期：2020-03-21

点击分享查看原文

点击收藏

阅读更多本刊最新论文