摘要
为了保证光催化的高光吸收和电化学动力学,构建分级多孔光催化剂十分必要.类石墨相氮化碳(g-C_(3)N_(4))易于合成、理化性质稳定、稳定性好和带隙合适等优点,特别是其可调的微/纳米结构,使其成为分级多孔光催化剂一个很好的选择.然而,具有层次孔的g-C_(3)N_(4)的简易制备仍然是一个难点.本文中,我们首次用均匀的有机微结构作为软模板,用简单方法制备了分级多孔g-C_(3)N_(4).该有机微纳结构模板是在硫脲前驱体溶液中原位形成的,与g-C_(3)N_(4)相似的π共轭结构使其能够有效修饰g-C_(3)N_(4)的分子结构.结果表明,合成的g-C_(3)N_(4)具有分级的中孔和大孔,比表面积为27.34 m^(2)g^(−1),孔体积为0.18 cm^(3)g^(−1),分别是未改性g-C_(3)N_(4)的6.2倍和9.0倍.这种分级多孔结构有利于电荷/质量传输过程,使其光降解有机污染物能力增强了2.4倍.同时,此光催化剂具有良好的光稳定性,长期使用100分钟后效率仅损失20%.
It is necessary to construct hierarchically porous photocatalysts to ensure high light absorption and electrochemical kinetics in photocatalysis.Carbon nitride(g-C_(3)N_(4))appears to be a favorable choice,especially the tunable hollow micro/nanostructure.However,the facile preparation of g-C_(3)N_(4)with hierarchical pores still faces challenge.Here,we firstly report a facile preparation of hierarchically porous g-C_(3)N_(4)with uniform organic microstructure as a soft template.The template is in situ formed in thiourea precursor solution,and its similarπ-conjugated structure to g-C_(3)N_(4)makes it effective in modifying the condensation of g-C_(3)N_(4).The layer thickness of the as-prepared g-C_(3)N_(4)is about 3–4 nm.And the resultant g-C_(3)N_(4)possesses hierarchical meso/macropores with a specific surface area of 27.34 m^(2)g^(−1)and pore volume of 0.18 cm^(3)g^(−1),approximately 6.2 and 9.0 times,respectively,higher than that of the unmodified one.This favors the charge/mass transport process,hence rendering the catalyst a 2.4-fold enhancement in photodegrading organic pollutant with H+and·O2−as the predominant species.At the same time,the photostability can be guaranteed with only 20%loss of its efficiency after long-term use.
作者
董嘉祺
巩正奇
陈颖芝
郝国栋
周文杰
李家馨
杨明强
邓荣胜
王鲁宁
Jiaqi Dong;Zhengqi Gong;Yingzhi Chen;Guodong Hao;Wenjie Zhou;Jiaxin Li;Mingqiang Yang;Rongsheng Deng;Lu-Ning Wang(School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China;Shunde Graduate School of University of Science and Technology Beijing,Foshan 528399,China;School of Chemistry and Chemical Engineering,Mudanjiang Normal University,Mudanjiang 157011,China)
基金
This work was financially supported by the National Key R&D Program of China(2021YFB3802200)
the Scientific and Technological Innovation Foundation of Shunde Graduate School,University of Science and Technology Beijing(BK19AE027 and BK20BE022).
