层状双金属氢氧化物负载碳点复合材料对土壤中外源化肥氮素转化的影响  

Impacts of CDs@LDHs composite on the external nitrogen transformation in soil

作　　者：张文博[1] 潘柯颖 张留洋 曹睿晞 杨文轩 王薇[1] 闫怡新[1] ZHANG Wenbo;PAN Keying;ZHANG Liuyang;CAO Ruixi;YANG Wenxuan;WANG Wei;YAN Yixin(School of Ecology and Environment,Zhengzhou University,Zhengzhou 450001,China)

机构地区：[1]郑州大学生态与环境学院,河南郑州450001

出　　处：《生态产业科学与磷氟工程》2024年第7期22-26,41,共6页Eco-industry Science & Phosphorus Fluorine Engineering

基　　金：国家重点研发计划项目(2021YFD1700900);郑州大学创新创业训练计划项目(2023CXCY575)。

摘　　要：农业生产离不开氮肥,但是实际应用中氮肥利用率较低,过剩的氮素会挥发至大气或者转化为硝酸盐进入地下水,导致营养流失和环境污染。采用吸附剂对土壤氮素进行固定是解决这一问题的有效途径之一。采用共沉淀法制备层状双金属氢氧化物(LDHs),微波法制备碳点胶体溶液(CDs),并将二者复合得到层状双金属氢氧化物负载碳点(CDs@LDHs)复合材料,通过X射线衍射和透射电子显微镜等方法对其组成和外观形貌进行表征,并测定其对铵态氮的吸附和解吸性能。结果表明,CDs@LDHs在常温和中性条件下吸附效果良好,且具有缓慢解吸性能,可有效缓冲高强度外源氮肥施加带来的影响;CDs@LDHs对施用不同外源氮肥(氯化铵、尿素和鸡粪有机肥)的土壤具有显著的固氮效果,施用有机肥土壤硝化速率可降低50%以上,氨挥发可降低20%左右。The application of nitrogen fertilizer is indispensable in agricultural production.However,the practical utilization efficiency of nitrogen fertilizer remains low,with excess nitrogen being volatilized into the atmosphere or converted into nitrate and leaching into groundwater.To alleviate this problem,the implementation of nitrogen stabilizer has emerged as an effective approach.The present study involves the synthesis of LDHs via co-precipitation method,preparation of CDs using microwave technique,and subsequent formation of CDs@LDHs composite.X-ray diffraction and transmission electron microscopy are employed to characterize the composition and morphology of CDs@LDHs composite,while adsorption and desorption performance towards ammonium nitrogen are evaluated.The findings demonstrate that CDs@LDHs composite exhibits excellent adsorption efficacy under ambient temperature and neutral conditions,along with a gradual desorption behavior that effectively mitigates the impact of high-intensity external nitrogen fertilizers.Further investigations reveal significant nitrogen fixation effects of CDs@LDHs composite on various external nitrogen fertilizers such as ammonium chloride,urea and organic fertilizer derived from chicken manure.Notably,when applied to organic fertilizer,it can reduce nitrification rate and ammonia volatilization by over 50%and approximately 20%.

关 键 词：CDs@LDHs复合材料 氮素固持 氯化铵 尿素 有机肥 

分 类 号：TQ449.4[化学工程—化学肥料工业]