摘要
为解决赤铁矿(α-Fe_(2)O_(3))和石墨相氮化碳(g-C_(3)N_(4))光催化活性低的问题,设计了一种采用液固混合-焙烧制取α-Fe_(2)O_(3)/g-C_(3)N_(4)复合光催化剂的方法。通过在可见光照射下光催化还原Cr(Ⅵ)实验研究合成的α-Fe_(2)O_(3)/g-C_(3)N_(4)复合物的光催化性能,并通过光电化学性能测试及能带结构分析探究其光催化活性增大的原因。结果表明:所合成的α-Fe_(2)O_(3)/g-C_(3)N_(4)复合物具有显著优于α-Fe_(2)O_(3)和g-C_(3)N_(4)的光催化活性,其光催化还原Cr(Ⅵ)的反应速率常数(k)为0.026 min^(-1),分别是g-C_(3)N_(4)(k=0.004 min^(-1))的6.5倍和α-Fe_(2)O_(3)(k=0.003 min^(-1))的8.7倍;α-Fe_(2)O_(3)/g-C_(3)N_(4)复合物为Ⅰ型异质结,能有效提高光生空穴与电子的分离及转移效率,是导致其光催化活性升高的原因。所设计的合成方法简单易行、成本低且合成的α-Fe_(2)O_(3)/g-C_(3)N_(4)复合物光催化还原Cr(Ⅵ)性能好,为Cr(Ⅵ)废水处理开发了一种有应用潜力的可见光催化剂。
In order to solve the problem of low photocatalytic activity of hematite(α-Fe_(2)O_(3))and graphite-phase carbon nitride(g-C_(3)N_(4)),α-Fe_(2)O_(3)/g-C_(3)N_(4)composite photocatalyst was designed and prepared by liquid-solid mixing-calcining method.The photocatalytic performance of the as-synthesizedα-Fe_(2)O_(3)/g-C_(3)N_(4)composite was studied via photocatalytic reduction of Cr(VI)under visible-light irradiation,and the reasons for its increased photocatalytic activity were investigated by photoelectrochemical property tests and energy band structure analysis.The results demonstrate that theα-Fe_(2)O_(3)/g-C_(3)N_(4)composite has notably superior photocatalytic activity thanα-Fe_(2)O_(3)and g-C_(3)N_(4).The reaction rate constant(k)of Cr(VI)reduction onα-Fe_(2)O_(3)/g-C_(3)N_(4)composite is 0.026 min^(-1),which is 6.5 times than that on g-C_(3)N_(4)(k=0.004 min^(-1))and 8.7 times than that onα-Fe_(2)O_(3)(k=0.003 min^(-1)).α-Fe_(2)O_(3)/g-C_(3)N_(4)composite is of type-I heterojunction,which can effectively improve the separation and transfer efficiency of photogenerated holes and electrons,and this is the reason for the improvement of its photocatalytic activity.The designed synthesis method is facile,practicable,low-cost,and the synthesizedα-Fe_(2)O_(3)/g-C_(3)N_(4)composite possesses good performance in photocatalytic reduction of Cr(VI),so this study has developed a potential visible-light photocatalyst for the treatment of Cr(VI)wastewater.
作者
张永才
侯振华
吴迪
毕昌军
侯建华
ZHANG Yongcai;HOU Zhenhua;WU Di;BI Changjun;HOU Jianhua(School of Chemistry and Chemical Engineering,Yangzhou University,Yangzhou 225002,Jiangsu,China;Jiangxi Xinda Hangke New Material Technology Co.,Ltd.,Nanchang 330599,China;College of Environmental Science and Engineering,Yangzhou University,Yangzhou 225009,Jiangsu,China)
出处
《实验室研究与探索》
CAS
北大核心
2023年第9期6-11,共6页
Research and Exploration In Laboratory
基金
国家自然科学基金项目(51602281)
江苏高校“青蓝工程”项目(苏教师函(2021)11号)
扬州市扬州大学市校合作创新平台建设项目(YZ2020263-08)
扬州大学自制实验仪器设备专项(YZUZZ2022-13)。
关键词
赤铁矿
石墨相氮化碳
复合物
光催化
六价铬还原
hemative(α-Fe_(2)O_(3))
graphite phase carbon nitride(g-C_(3)N_(4))
composite
photocatalysis
Cr(VI)reduction
