Ti_(1)Li_(3)Al_(2)-LDHs@OBAC的结构及其光催化CO_(2)还原特性  

Structure and Photocatalytic CO_(2) Reduction Characteristics of Ti_(1)Li_(3)Al_(2)-LDHs@OBAC

作　　者：凌洁 周安宁[1] 王文珍[3] 李瑞琪[2] 李纹龙 LING Jie;ZHOU Anning;WANG Wenzhen;LI Ruiqi;LI Wenlong(College of Chemistry&Chemical Engineering,Xi′an University of Science and Technology,Xi′an 710054,China;College of Coal&Chemical Industry,Shaanxi Energy Institute,Xianyang 712000,China;College of Chemistry&Chemical Engineering,Xi′an Shiyou University,Xi′an 710065,China)

机构地区：[1]西安科技大学化学与化工学院,陕西西安710054 [2]陕西能源职业技术学院煤炭与化工产业学院,陕西咸阳712000 [3]西安石油大学化学化工学院,陕西西安710065

出　　处：《石油学报（石油加工）》2024年第5期1275-1286,共12页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家自然科学基金项目(51674194);陕西省自然科学基础研究计划项目(2021JQ-886);陕西高校青年杰出人才支持计划项目;咸阳市创新能力支撑计划项目(L2023-CXNL-CXRC-010)资助。

摘　　要：采用尿素水热法制备了类水滑石(Ti_(1)Li_(3)Al_(2)-LDHs),将其负载于氧化椰壳活性炭(OBAC)表面制得Ti_(1)Li_(3)Al_(2)-LDHs@OBAC光催化剂,通过XRD、FT-IR、SEM、TEM、N_(2)吸附-脱附等温线、XPS、CO_(2)静态吸附等温线、CO_(2)-TPD、UV-Vis和EIS等手段对其进行表征,基于Ti_(1)Li_(3)Al_(2)-LDHs构建Ti_(1)Li_(3)Al_(2)-LDHs@OBAC的结构模型,利用CO_(2)-水反应体系研究其光催化CO_(2)还原特性。结果表明:Ti_(1)Li_(3)Al_(2)-LDHs中Ti^(4+)、Li^(+)取代MgAl-LDHs中Mg^(2+)形成以Ti^(4+)、Li^(+)为中心的八面体结构,斜方堆积(3R)形成2D层片结构,层间阴离子为CO_(2)-3。Ti_(1)Li_(3)Al_(2)-LDHs@OBAC呈球状包覆结构,六边形层片Ti_(1)Li_(3)Al_(2)-LDHs垂直生长于OBAC表面;在反应温度80℃、反应时间8 h条件下,Ti_(1)Li_(3)Al_(2)-LDHs@OBAC的光催化CO_(2)还原CO产率、CH 4产率和CO/CH 4产率比分别为42.62、1.18μmol/g和36。OBAC的碳缺陷增强了催化剂对CO_(2)的吸附活化能力,显著提高Ti_(1)Li_(3)Al_(2)-LDHs@OBAC光催化CO_(2)还原活性。Ti_(1)Li_(3)Al_(2)-LDHs was synthesized using the urea hydrothermal method,and was loaded on the surface of oxidized coconut shell activated carbon(OBAC)to prepare Ti_(1)Li_(3)Al_(2)-LDHs@OBAC photocatalyst,which was further characterized by XRD,FT-IR,SEM,TEM,N_(2)adsorption-desorption isotherms,XPS,CO_(2)static adsorption isotherms,CO_(2)-TPD,UV-Vis and EIS.The structural model of Ti_(1)Li_(3)Al_(2)-LDHs@OBAC was constructed based on Ti_(1)Li_(3)Al_(2)-LDHs,and the photocatalytic CO_(2)reduction characteristics of the photocatalyst were studied using CO_(2)-water reaction system.The results indicate that Ti^(4+)and Li^(+)ions in Ti_(1)Li_(3)Al_(2)-LDHs replace Mg^(2+)in MgAl-LDHs,thus forming a composite octahedron structure with Ti^(4+)and Li^(+)at the center;a 2D layered structure is formed in an orthorhombic stacking(3R)manner,and the interlayer anions are CO_(2)-3.Ti_(1)Li_(3)Al_(2)-LDHs@OBAC presents a coated spherical morphology,and Ti_(1)Li_(3)Al_(2)-LDHs with a hexagonal lamellar structure are vertically grown on the surface of OBAC.The yields of CO,CH 4 and yield rate of CO/CH 4 of Ti_(1)Li_(3)Al_(2)-LDHs@OBAC after photocatalytic CO_(2)reduction are 42.62,1.18μmol/g and 36,respectively at the temperature of 80℃and reaction time of 8 h.The carbon defects of OBAC enhance its adsorption and activation ability to CO_(2),thus significantly improving the photocatalytic CO_(2)reduction activity of Ti_(1)Li_(3)Al_(2)-LDHs@OBAC.

关 键 词：类水滑石 光催化 CO_(2)还原 活性炭 结构 复合材料 

分 类 号：TQ426[化学工程]