N doped carbon quantum dots modified defect-rich g-C3N4 for enhanced photocatalytic combined pollutions degradation and hydrogen evolution
N doped carbon quantum dots modified defect-rich g-C3N4 for enhanced photocatalytic combined pollutions degradation and hydrogen evolution
复制标题
N掺杂碳量子点修饰富缺陷g-C3N4，用于增强光催化复合污染物降解和析氢
DOI：
10.1016/j.colsurfa.2020.124552
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发表时间：
2020-04-20
影响因子：
5.2
通讯作者：
Zhou, Jianguo
中科院分区：
文献类型：
--
作者：
Liu, Haiping;Liang, Jing;Zhou, Jianguo
开发无金属助催化剂是光催化技术在环境废水处理和水分解领域的重要研究方向。采用浸渍法制备了氮掺杂碳量子点（NCDs）改性富缺陷g-C3N4（DCN）。系统研究了NCDs/DCN的结构、光学和电学性质。NCDs/DCN具有良好的可见光吸收、窄禁带和电子转移能力，有利于光催化去除复合污染物，同时产生H2和降解罗丹明B（RhB）。在OFL/Cr（VI）、BPA/Cr（VI）和CIP/Cr（VI）三种复合污染物体系中，NCDs/DCN的去除率均高于单一体系，这是由于有机污染物氧化与Cr（VI）还原的协同效应所致.自由基猝灭实验、光谱技术和电子自旋共振（ESR）证实，Cr（VI）可被导带电子（CB）还原，而H（+）和O-2（中心点-）自由基主导OFL的降解。优化后的NCDs/DCN表现出优异的同时光催化产氢活性和RhB降解，其产氢速率为3.68 μ mol·h（-1）·g（-1），RhB去除率为100%。光催化同时去除污染物和协同产生H-2和RHB降解的活性为真实的废水修复应用和能源利用提供了有前途的策略。
Exploiting metal-free cocatalysts is of huge interest for photocatalytic technology in environmental wastewater remediation and water splitting fields. The N doped carbon quantum dots (NCDs) modified defect-rich g-C3N4 (DCN) was prepared through impregnation method. The structural, optical and electronic properties of NCDs/DCN were systematically investigated. The NCDs/DCN with outstanding visible light absorption, narrowed gap and electron transfer ability were conducive to combined pollutions photocatalytic removal and simultaneous H(2 )production and rhodamine B (RhB) degradation. The resulting NCDs/DCN performed much higher removal efficiency in different combined pollutions systems containing OFL/Cr (VI), BPA/Cr (VI) and CIP/Cr (VI) than in single system owing to the synergistic effect between organic pollution oxidation and Cr (VI) reduction. The free-radical quenching experiments, spectral technology and electron spin resonance (ESR) confirmed that Cr(VI) can be reduced by the conduction band (CB) electrons, and the h(+) and O-2(center dot-) radicals dominated OFL degradation. The optimized NCDs/DCN displayed excellent simultaneously photocatalytic H-2 production activity and RhB degradation with the H-2 evolution rate of 3.68 mu mol.h(-1).g(-1) and 100% RhB removal efficiency. The photocatalytic activity of simultaneous combined pollutions removal and synergistic H-2 generation and RHB degradation provides a promising strategy for real wastewater remediation applications and energy utilization.