升温速率对尿素热解制g-C_(3)N_(4)光催化剂构效影响研究  

Study on effect of heating rate on structure-activity of g-C_(3)N_(4) photocatalyst by pyrolysis of urea

作　　者：杨文博 吴潘[1] 何坚[1] 刘长军[1] 蒋炜[1] YANG Wenbo;WU Pan;HE Jian;LIU Changjun;JIANG Wei(School of Chemical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学化学工程学院,四川成都610065

出　　处：《无机盐工业》2022年第4期169-174,共6页Inorganic Chemicals Industry

基　　金：国家自然科学基金(21978181)。

摘　　要：尿素热解可制备高附加值下游产品石墨相氮化碳(g-C_(3)N_(4)),热解条件显著影响其光催化性能。以工业级尿素为前驱体,考察了升温速率对产物g-C_(3)N_(4)结构和光催化性能的影响,并用于光催化氧化降解有机染料和光催化还原生产双氧水。结果表明,快速升温(15℃/min)所得g-C_(3)N_(4)(GCN-15)结晶度高、无定型结构少、带隙窄、光利用率高、共轭结构完整,利于光生电子传递,因此具有更好的光催化性能。其对罗丹明B(RhB)和亚甲基蓝(MB)光氧化降解速率分别是慢速升温(2℃/min)所得g-C_(3)N_(4)(GCN-2)的4倍和2倍,8 h光还原双氧水产量提高18.37%。High value added downstream products graphitic carbon nitride(g-C_(3)N_(4))can be prepared by pyrolysis of urea,but its photocatalytic performance is significantly affected by pyrolysis conditions.Industrial grade urea was used as precursor,the effect of heating rate on the structure and photocatalytic performance of g-C_(3)N_(4) was investigated,and g-C_(3)N_(4)was used for photocatalytic oxidation degradation of organic dyes and photocatalytic reduction to produce H_(2)O_(2).The results showed that g-C_(3)N_(4)(GCN-15)with rapid heating rate(15℃/min)had high crystallinity,less amorphous structure,more complete conjugated structure and narrow band gap,which was beneficial to the transfer of photogenerated electrons and the improvement of photocatalytic performance.The photodegradation rates of RhB and MB by GCN-15 were 4 and 2 times higher than those by GCN-2,respectively,and the yield of H_(2)O_(2) produced in 8 hours was increased by 18.37%.

关 键 词：石墨相氮化碳 工业级尿素热解 构效关系 升温速率 光催化 

分 类 号：O643.36[理学—物理化学]