Efficient degradation of tetracycline by RGO@black titanium dioxide nanofluid via enhanced catalysis and photothermal conversion.
Efficient degradation of tetracycline by RGO@black titanium dioxide nanofluid via enhanced catalysis and photothermal conversion.
复制标题
RGO@黑色二氧化钛纳米流体通过增强催化和光热转化有效降解四环素。
DOI：
10.1016/j.scitotenv.2021.147536
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发表时间：
2021
影响因子：
9.8
通讯作者：
Yanan Liu
中科院分区：
文献类型：
--
作者：
Dahai Zhu;L. Cai;Zhuyu Sun;Ai Zhang;P. Héroux;Hyunjung Kim;Wei Yu;Yanan Liu
由于太阳能利用率低，光催化降解污染物的应用受到限制。采用高温煅烧和水热两步法合成了一种由还原氧化石墨烯@黑二氧化钛（RGO@BT）纳米流体组成的具有有效全光谱（从紫外到红外）吸收的光热催化剂。此外，还验证了RGO@BT纳米流体对四环素的光热催化性能。在模拟全球标准光谱太阳光（AM 1.5G，1000 W m−2）下，光热催化过程显著增强了四环素的降解。最大光热转换效率达到91.8%，在用200 mg L−1RGO@BT纳米流体处理120 min后，四环素降解率（40 mg L−1）达到94.7%。空穴、自由基dotOH和自由基dotO 2 −被发现是光热催化过程中的主要活性物种。此外，热量是在不使用任何外部能源的情况下从光能自发转换而来的。升高的系统温度有利于四环素的降解，基于Arrhenius行为。这些发现为通过太阳能高效光热转换材料提高光催化降解有机污染物的效率提供了新的思路。
The applications of photocatalytic pollutant degradation have remained limited due to the low efficiency of solar energy utilization. In this study, a photothermal catalyst consisting of reduced graphene oxide @ black TiO2(RGO@BT) nanofluid with effective full-spectrum (from ultraviolet to infrared light) absorption was synthesized by a typical two-step method of high temperature calcination and hydrothermal method. Moreover, the photothermal catalytic performance of the RGO@BT nanofluid on tetracycline was verified. Compared with individual processes (i.e, photocatalysis and thermocatalysis), the photothermal catalytic process significantly enhanced tetracycline degradation under simulated global standard spectrum sunlight (AM 1.5G, 1000 W m−2). The maximum photothermal conversion efficiency reached 91.8%, which resulted in 94.7% tetracycline degradation (40 mg L−1) after 120 min of treatment with 200 mg L−1RGO@BT nanofluid. Holes, radical dotOH, and radical dotO2−were found to be the main active species during the photothermal catalytic process. Moreover, heat was spontaneously converted from light energy without the use of any external energy source. The elevated system temperature facilitated the tetracycline degradation based on the Arrhenius behavior. These findings provide insights into the improvement of photocatalytic efficiency in organic contaminant degradationviasolar energy-efficient photothermal conversion materials.