Photocatalytic behavior of biochar-modified carbon nitride with enriched visible-light reactivity
Photocatalytic behavior of biochar-modified carbon nitride with enriched visible-light reactivity
复制标题
具有丰富可见光反应活性的生物炭改性氮化碳的光催化行为
DOI：
10.1016/j.chemosphere.2019.124713
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发表时间：
2020-01-01
期刊：
影响因子：
8.8
通讯作者：
Wang, Xiaozhi
中科院分区：
文献类型：
--
作者：
Meng, Lirong;Yin, Wenhua;Wang, Xiaozhi
超薄层状结构和改性的带隙是提高半导体工业中各种材料光催化性能的两种有效策略。在本研究中，我们结合这两种策略在一种材料中形成碳掺杂的石墨碳氮化物（g-C3 N4）纳米层状结构的三聚氰胺热缩合的方法，在不同的质量比的生物炭的存在下。表征结果表明，最佳配比的复合材料保留了g-C3 N4聚合物骨架和与g-C3 N4的键合。生物炭是通过π-π堆积相互作用和醚键桥形成的。生物炭所提供的π共轭电子体系可以提高电荷分离效率。超薄结构还缩短了光生电子迁移到材料表面的距离，增大了材料的比表面积。碳的存在缩小了g-C3 N4的带隙，并在更宽的波长范围内增加了光吸收。生物炭/三聚氰胺比例为1：15时，降解罗丹明和甲基橙子的速度分别是g-C3 N4的2.8倍和5倍。此外，催化剂在4个循环中表现出良好的稳定性。除此之外，来自废弃生物质的生物炭可以被认为是改性g-C3 N4基光催化剂的可持续、具有成本效益和高效的选择。(C)2019爱思唯尔有限公司版权所有。
Ultra-thin layered structures and modified bandgaps are two efficient strategies to increase the photocatalytic performance of various materials for the semiconductor industry. In the present study, we combined both strategies in one material to form carbon-doped graphitic carbon nitride (g-C3N4) nanolayered structures by the method of melamine thermal condensation, in the presence of different mass ratios of biochar. The characterization showed that the composite with the best ratio retained the g-C3N4 polymeric framework and the bond with g-C3N4. The biochar was established via pi-pi stacking interactions and ether bond bridges. The pi-conjugated electron systems provided from biochar can elevate charge separation efficiency. The ultra-thin structure also curtailed the distance of photogenerated electrons migrating to the surface and enlarge specific surface area of materials. The presence of carbon narrowed the bandgap and increased light absorption at a wider range of wavelengths of g-C3N4. The biochar/melamine ratio of 1:15 presented the best performance, 2.8 and 5 times faster than g-C3N4 degradating Rhodamine and Methyl Orange, respectively. Moreover, the catalyst presented a good stability for 4 cycles. In addition to that, biochar from waste biomass can be considered a sustainable, cost-effective, and efficient option to modify g-C3N4-based photocatalysts. (C) 2019 Elsevier Ltd. All rights reserved.