钒-氮共掺杂碳基介孔纳米材料的制备及氮还原电催化性能  

V-N Co-doped Mesoporous Carbon Nanomaterials as Catalysts for Artificial N2 Reduction

作　　者：李琳 任慧敏 卫博慧 李军[2] 王杰[2] 李晖[2] 姚陈忠[2,3] LI Lin;REN Huimin;WEI Bohui;LI Jun;WANG Jie;LI Hui;YAO Chenzhong(School of Chemistry and Materials Science,Shanxi Normal University,Linfen,Shanxi 041004,China;Department of Applied Chemistry,Yuncheng University,Yuncheng,Shanxi 044000,China;Key Laboratory of Education Ministry for Coal Science and Technology,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]山西师范大学化学与材料科学学院,山西临汾041004 [2]运城学院应用化学系,山西运城044000 [3]太原理工大学煤科学与技术教育部重点实验室,太原030024

出　　处：《应用化学》2020年第8期930-938,共9页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金项目(U1810110,21576230,51808485);中国国家留学基金、山西省基金项目(201903D121105,201701D211004,201701D221045);运城学院重点学科项目、塑料卫生与安全质量评价技术北京市重点实验室开放课题(BS201709);太原理工大学煤科学与技术国家重点实验室开放课题(MKX201904)资助。

摘　　要：电化学固氮技术由于可在温和条件下进行,为肥料低成本生产提供了新策略,但高稳定性和高活性电催化剂的选择是其关键技术。本文采用溶胶凝胶法合成了钒掺杂ZIF-8,以此为前驱体进一步高温碳化,合成了纳米介孔钒-氮共掺杂碳基电化学还原氮(NRR)催化剂。利用透射电子显微镜、X射线衍射、X光电子能谱和Raman光谱等对催化剂进行了表征分析。所得催化剂呈现出高度无序的三维多孔碳结构。催化剂中存在适量的V5+、碳化氮和吡啶氮对NRR起到明显促进作用。当前驱体中钒锌比为0.125,在N2气气氛保护下1100℃热处理获得催化剂具有最佳NRR性能,在0.1 mol/L KOH电解质溶液中,当外加电压为-0.4 V时,氨的生产速率可达7.092μmol/(cm^2·h),法拉第效率为23.88%,且催化剂具有良好的稳定性。Compared with the Haber-Bosch process,electrochemical nitrogen fixation can directly convert N 2 to NH 3 under mild environmental conditions,which is the building block of fertilizer for agricultural production.However,the screening of nitrogen reduction electrocatalyst with high activity and high stability is the most important.Here,vanadium doped ZIF-8 was synthesized by the sol-gel method,and used as the precursor to prepare mesoporous carbon electrochemical N 2 reduction reaction(NRR)catalysts at high temperature.The catalysts were characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and Raman spectroscopy,etc.The catalyst shows a highly disordered three-dimensional carbon structure.The presence of appropriate amount of V 5+,nitrogen carbide and pyridine nitrogen in the catalyst can promote NRR significantly.In the 0.1 mol/L KOH electrolyte solution,with V doped amount of 1/8 and the applied potential of-0.4 V,the catalyst has the best NRR performance at the calcination temperature of 1100℃.The ammonia production rate can reach 7.092 mol/(cm 2·h)and the Faraday efficiency(FE%)is 23.88%.Meanwhile,its current density has a slight fluctuation at-0.4 V for 18 h electrochemical reaction,further suggesting that V-N co-doped carbon based mesoporous nanomaterials has high durability.

关 键 词：介孔碳 钒氮共掺杂 氮还原 电催化 

分 类 号：O646[理学—物理化学]