Z型异质结1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)的构建及可见光催化降解甲基橙  

Construction of Z-scheme heterojunction 1D/2D g-C_(3)N_(5)/g-C_(3)N_(4) and visible photocatalytic degradation of methyl orange

作　　者：卜义夫 刘思乐 闫海生 吴静 田川 陶洋 BU Yifu;LIU Sile;YAN Haisheng;WU Jing;TIAN Chuan;TAO Yang(Department of Chemistry and Chemical Engineering,Shenyang Science and Technology University,Shenyang 110167,China;Zhejiang Qinyan Technology Co.,Ltd.,Shaoxing 312300,Zhejiang,China;Ningbo Institute of Materials Technology&Engineering,Chinese Academy of Science,Ningbo 315201,Zhejiang,China;College of Chemical Engineering,Shenyang University of Chemical Technology,Shenyang 110142,China;Chemical Safety Technology and Engineering Center,Shenyang Institute of Chemical Engineering Shenyang 110020,China)

机构地区：[1]沈阳科技学院化学与化工系,沈阳110167 [2]浙江秦燕科技股份有限公司,浙江绍兴312300 [3]中国科学院宁波材料技术与工程研究所,浙江宁波315201 [4]沈阳化工大学化学工程学院,沈阳110142 [5]沈阳化工研究院化工安全技术与工程中心,沈阳110020

出　　处：《材料工程》2024年第10期170-182,共13页Journal of Materials Engineering

基　　金：国家级大学生创新创业训练计划项目(202213621001);辽宁省教育厅2022年高等学校基本科研项目面上项目(LJKM20221989);沈阳科技学院科学研究项目(ZD-2024-02)。

摘　　要：以三聚氰胺和3-氨基-1,2,4-三唑为原料,通过直接热聚合法制备1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)异质结光催化材料。通过XRD,XPS,SEM等表征手段对光催化材料的晶型、化学组成、形貌以及光电化学性质等进行表征。以甲基橙(MO)为目标污染物,500 W氙灯作为可见光光源,研究1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)异质结光催化材料的光催化活性,同时通过活性物质捕捉实验和电子顺磁共振波谱(e1ectron spin resonance,ESR)表征研究体系的活性物质。结果表明:一维g-C_(3)N_(5)纳米棒和二维g-C_(3)N_(4)纳米片的无序堆叠增加了活性位点的数量,g-C_(3)N_(5)与g-C_(3)N_(4)之间Z型异质结的形成,提高其对可见光的吸收强度和光谱范围,抑制了光电子-空穴的复合,g-C_(3)N_(5)与g-C_(3)N_(4)相似的π-π^(*)共轭体系的相互叠加降低了电荷转移的传质阻力,提高了其光催化活性。可见光照射30 min,20 mg的1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)光催化材料对50 mL浓度为10 mg/L的MO溶液几乎降解完全,反应的表观速率常数为0.14836 min^(-1),循环使用5次后,1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)光催化材料对MO的光催化降解率为92.2%,这说明其具有良好的稳定性。活性物质捕捉实验和ESR表征表明:1D/2D g-C_(2)N_(5)/g-C_(3)N_(4)光催化材料光催化降解MO体系的主要活性物质是·O_(2)^(-)和h^(+),且MO的光催化降解反应是一个复杂的断键和氧化过程。1D/2D g-C_(3)N_(5)/g-C_(3)N_(4) heterojunction photocatalysts were prepared by a direct thermal polymerization method using melamine and 3-amino-1,2,4-triazole as raw materials.The crystal form,chemical composition,morphology and photoelectric chemical properties of the photocatalytic materials were characterized by XRD,XPS,SEM.Photocatalytic activity of 1D/2D g-C_(3)N_(5)/g-C_(3)N_(4) heterojunction photocatalyst was studied using methyl orange(MO)as target pollutant and 500 W xenon lamp as visible light source.The active substances of the system were studied by active substance capture experiment and ESR characterization.The results show that the disordered stacking of one-dimensional g-C_(3)N_(5) nanorods and two-dimensional g-C_(3)N_(4) nanosheets increases the number of active sites.The formation of Z-scheme heterojunction between g-C_(3)N_(5) and g-C_(3)N_(4) improves the absorption intensity and spectral range of visible light,and inhibits the recombination of photoelectrons and holes.The superposition ofπ-π*conjugated systems similar to g-C_(3)N_(5) and g-C_(3)N_(4) reduces the mass transfer resistance of charge transfer and improves its photocatalytic activity.Under visible light irradiation for 30 min,20 mg of 1D/2D g-C_(3)N_(5)/g-C_(3)N_(4) photocatalytic material almost completely degraded 50 mL of 10 mg/L MO solution,and the apparent rate constant is 0.14836 min^(−1).After 5 cycles,the photocatalytic degradation rate of 1D/2D g-C_(3)N_(5)/g-C_(3)N_(4) photocatalytic material for MO is 92.2%,indicating its good stability.The capture experiment of active substances and ESR characterization show that the main active substances in the photocatalytic degradation of MO system by g-C_(3)N_(5)/g-C_(3)N_(4) photocatalyst are•O^(-)_(2) and h^(+),and the photocatalytic degradation of MO was a complex bond breaking and oxidation process.

关 键 词：光催化降解 直接热聚合 1D/2D g-C_(3)N_(5)/g-C_(3)N_(4) 异质结 π-π^(*)共轭 甲基橙 Z型机制 

分 类 号：TQ426[化学工程] O643.3[理学—物理化学]