介孔氮化铌粉体的制备及电化学性能  

Preparation and Electrochemical Performance of Mesoporous Niobium Nitride Powders

作　　者：崔帅 呼世磊 吕东风 崔燚 魏颖娜 魏恒勇 卜景龙 陈越军 CUI Shuai;HU Shilei;LYU Dongfeng;CUI Yi;WEI Yingna;WEI Hengyong;BU Jinglong;CHEN Yuejun(College of Material Science and Engineering,North China University of Science and Technology,Tangshan 063210,China;Hebei Provincial Key Laboratory of Inorganic Nonmetallic Materials,Tangshan 063210,China)

机构地区：[1]华北理工大学材料科学与工程学院,唐山063210 [2]河北省无机非金属材料重点实验室,唐山063210

出　　处：《材料导报》2020年第14期14009-14015,共7页Materials Reports

基　　金：国家自然科学基金(51272066);河北省自然科学基金(E2019209474)。

摘　　要：以五氯化铌(NbCl 5)为铌源,P123为模板剂,氰胺为结构稳定剂,采用溶剂热法制备Nb 2O 5前驱体粉体,然后将Nb 2O 5粉体在800℃氨气中进行还原氮化反应制备介孔氮化铌粉体。采用XRD、XPS、SEM、BET和TEM表征了介孔粉体的物相、形貌及孔结构。结果表明,粉体为立方Nb 4N 5相,呈近似球形颗粒状。从XPS分析中可以看出,粉体中主要含有Nb、N和O三种元素,并且在Nb元素的窄谱中,结合能为204.6 eV、207.2 eV和209.8 eV对应的结合键分别为Nb^3+-N、Nb^5+-N和Nb^5+-O,这表明氮化铌粉体中有Nb^3+和Nb^5+两种价态,且Nb^5+峰强高于Nb^3+,说明铌多以Nb^5+形式存在。粉体比表面积为39 m 2·g^-1,孔径为3~5 nm的孔结构比例较高,同时在8~15 nm范围也存在较多的孔道结构。采用CV、GCD及EIS等测试其电化学性能,结果表明,CV曲线中并没有出现明显的氧化还原峰,主要表现为双电层特征,其储能主要受电极材料表面电荷传递过程控制。样品在电流密度为10 mA·g^-1时的比电容为90 F·g^-1,样品的内在阻抗为0.82Ω,电荷转移阻抗为0.22Ω,当功率密度为480 W·kg^-1时,能量密度为7.2 Wh·kg^-1。Nb2O5 precursor powder was prepared by solvothermal method,NbCl5 as niobium source and P123 as the pore-forming agent,cyanamide as the structural stabilizer.The mesoporous niobium nitride powder was synthesized via nitrogen reduction of the mesoporous Nb2O5 powder at 800℃in NH 3.The phase and morphology were characterized by XRD,XPS,SEM,BET and TEM.The results show that the synthesized nio-bium nitride powder is cubic Nb 4N 5 phase,which is similar to spherical particles.It can be seen from the XPS analysis that the powder mainly contains three elements:Nb,N and O,and in the narrow spectrum of Nb elements,the binding energy is 204.6 eV,207.2 eV and 209.8 eV,and the corresponding bonds are Nb^3+-N,Nb^5+-N and Nb^5+-O,respectively,indicating that there are two valence states of Nb^3+and Nb^5+in the nitride powders.And the Nb^5+peak intensity is higher than Nb^3+,indicating that the niobium is present in the form of Nb^5+.The specific surface area of the powder is 39 m 2·g^-1,the pore structure in the range of 3—5 nm of powders has a high proportion,and there are also many pore structures in the range of 8—15 nm.The electrochemical properties were tested by CV,GCD and EIS.The results show that there is no obvious redox peak in CV curve,which is mainly characterized by double layer.The energy storage of niobium nitride powders is mainly controlled by the charge transfer process on the electrode surface.The specific capacitance is 90 F·g^-1 when the current density is 10 mA·g^-1.The internal resistance is 0.82Ω,and the ion diffusion impedance is 0.22Ω.When the power density is 480 kW·kg^-1,the energy density is 7.2 Wh·kg^-1.

关 键 词：NB 4N 5粉体 介孔 电化学 还原氮化 

分 类 号：TQ135.12[化学工程—无机化工]