Dong Guangzhi, Wen Yun, Fan Huiqing, Wang Chao, Cheng Zhenxiang, Zhang Mingchang, Ma Jiangwei, Zhang Shujun
State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University Xi'an 710072 PR China
Institute for Superconducting and Electronic Materials, Australia Institute of Innovative Materials, University of Wollongong Wollongong 2522 Australia.
RSC Adv. 2020 May 15;10(32):18632-18638. doi: 10.1039/d0ra01425g. eCollection 2020 May 14.
Graphitic carbon nitride (g-CN, CN) with nitrogen vacancies was synthesized by a controlled thermal etching method in a semi-closed air-conditioning system. The defect-modified g-CN shows an excellent photocatalytic performance demonstrated by water splitting under visible light irradiation. With proper heat-treatment durations such as 2 h (CN2) and 4 h (CN4) at 550 °C, the hydrogen production rates significantly increase to 100 μmol h and 72 μmol h, which are 11 times and 8 times the rate of the pristine CN (8.8 μmol h) respectively. The excellent hydrogen production performance of nitrogen defect modified CN2 is due to the synergy effect of the decreased band gap, enlarged specific surface area and increased separation/migration efficiency of photoinduced charge carriers. This simple defect engineering method provides a good paradigm to improve the photocatalytic performance by tailoring the electronic and physical structures of g-CN.
采用可控热蚀刻法在半封闭空调系统中合成了具有氮空位的石墨相氮化碳（g-CN，CN）。缺陷修饰的g-CN在可见光照射下表现出优异的光催化性能，通过水分解得以证明。在550℃下进行适当的热处理时间，如2小时（CN2）和4小时（CN4），产氢速率显著提高到100 μmol/h和72 μmol/h，分别是原始CN（8.8 μmol/h）产氢速率的11倍和8倍。氮缺陷修饰的CN2优异的产氢性能归因于带隙减小、比表面积增大以及光生载流子分离/迁移效率提高的协同效应。这种简单的缺陷工程方法为通过调整g-CN的电子和物理结构来提高光催化性能提供了一个良好的范例。
