(1. 內蒙古師范大學 物理與電子信息學院 功能材料物理與化學自治區(qū)重點實驗室，呼和浩特 010022；
2. 北京大學 化學與分子工程學院，北京 100871)
摘 要: 采用X射線衍射(XRD)和掃描電鏡(SEM)研究不同球磨時間下多壁碳納米管(CNTs)的微觀結構。XRD分析表明：隨著球磨時間的延長，CNTs的衍射峰明顯變弱，并伴有部分衍射峰消失。SEM結果發(fā)現(xiàn)：球磨使細長的CNTs斷裂，長度明顯變短；隨球磨時間的進一步延長，CNTs空心管狀結構破損。采用電化學方法測試添加未球磨和球磨不同時間CNTs導電劑的AB5型儲氫合金電極的電化學性能。結果表明：隨球磨時間的延長，合金電極的最大放電容量、放電性能及循環(huán)穩(wěn)定性均呈現(xiàn)出先提高后減弱的變化規(guī)律。當CNTs的球磨時間為2 h時，合金電極的最大放電容量和放電性能達最佳；當CNTs的球磨時間為2.5 h時，合金電極的循環(huán)穩(wěn)定性最佳。
關鍵字: 碳納米管；球磨；儲氫合金電極；電化學性能
（1. Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials, School of Physics and Electronic Information, Inner Mongolia Normal University, Hohhot 010022, China;
2. College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China）
Abstract:The microstructures of carbon nanotubes (CNTs) after milling for different time were characterized by XRD and SEM. XRD analysis results indicate that the intensity of the diffraction peaks of the milled carbon nanotubes signi？cantly decreases with increasing milling time. In addition, as the milling time increasing, all diffraction peaks gradually weaken and some peaks disappear. SEM observations show that ball milling is a good method to cut long CNTs into short ones. The tubular structure of CNTs is destroyed after milling for a long time. The electrochemical properties of AB5-type alloy electrodes added unmilled and milled CNTs were investigated. The results indicate that the maximum discharge capacities, discharge properties and cycle stabilities of the alloy electrodes improve firstly, and then degenerate with increasing of ball-milling time. The alloy electrode added CNTs milling for 2 h exhibits the best discharge capacity and discharge property. The alloy electrode added CNTs milling for 2.5 h shows the best cycle stability.
Key words: carbon nanotube; ball milling; hydrogen storage alloy electrode; electrochemical property
