本文主要研究内容
作者许江琳(2019)在《过渡金属磷(硫)化物/碳复合锂离子电池负极材料的制备及性能研究》一文中研究指出:锂离子电池得益于其高能量密度、高电压、高寿命等综合性能优势,已经作为一种新型的替代性能源。市场上目前应用的负极材料主要以石墨碳为主,可是由于其自身性质的缺陷,已经不能满足高效锂离子电池不断增长的需求,所以我们应该寻找容量更高稳定性更好的负极材料使锂离子电池的性能进一步提升。过渡金属磷化物、硫化物具有远高于石墨碳的理论容量、合适的电压平台和环境友好性,是非常理想的锂离子电池负极材料。但是,其自身依然存在电子传导性不足、充放电过程中会产生体积膨胀等问题,这会使他们的实际容量低于理论容量。本文针对过渡金属磷化物、硫化物的这些性质缺陷,采用简单的合成方法,通过碳材料(如碳纳米管)的原位生长让其与碳材料进行复合,利用疏松多孔的结构特征和原位生长的碳纳米管提高材料的电子传导性并且通过对抗体积变化应力来约束活性物质的结构变形,进而提高材料的电化学性能。主要的研究结果总结如下:1、通过自催化的方法在高温长时间煅烧的条件下使ZIF-67中的金属离子作为催化剂,使有机配体在形成碳框架的同时在表面原位催化生成直径约为3 nm的碳纳米管,再通过进一步的磷化过程,形成了碳纳米管交织的多孔CoP@N-(C/CNTs)。对其进行电池性能测试后,发现当电流密度为0.5 Ag-1时,它首次放/充电比容量分别为1215 mAh g-1/688 mA h g-1,并且在历经200次循环后保留600 mA h g-1的可逆容量,这是由于材料的多孔结构能够减轻锂离子嵌入/脱出过程中的应力形变,保持结构稳定,原位生长的碳纳米管可以为离子和电子的转移提供更多的通道和路径,提高材料的电子传导性。这种原位生长的碳纳米管合成方法简单,制备的复合材料性能优异,证明了这种自催化形成碳纳米管交织网络是一种非常简便有效的结构设计策略。2、利用Ni-MOF作为原始材料,在低温的条件下通过简单的两步煅烧步骤,生成了多孔碳球内包裹金属颗粒并在球体表面原位延伸出碳纳米管的纳米结构,再通过进一步的磷化最终形成Ni2P@C/CNTs。Ni2P纳米颗粒被很好地包裹在疏松多孔的碳球内,可以缓解Ni2P作为负极活性材料在电池循环放电和充电的过程中的体积变化和结构变形,多孔的结构提高了结构稳定性;碳球表面生长的碳纳米管为离子/电子的移动提供了更多的路径,增强了材料的电子传导性。Ni2P@C/CNTs材料作为锂离子电池负极材料时,在0.2 Ag-1的电流密度下,第一次放电/充电比容量为652 mAh g-1/443 mAh g-1,在300次循环后可逆容量依然保持442 mA h g-1,体现出了非常好的电化学稳定性。这种制备Ni2P@C-CNT的方法不需要高温煅烧的条件就可以原位生成碳纳米管,简单方便且经济环保,对碳纳米管与金属化合物的复合有一定的借鉴意义。3、以泡沫镍作为无粘合剂负极的集流体,在上面负载ZIF-67,再以ZIF-67/泡沫镍作为前驱体通过溶剂热反应将ZIF-67硫化后再进一步碳化,得到了多层纳米颗粒阵列的Co9S8/C/泡沫镍负极材料。在对其进行电化学性能测试后,多层纳米颗粒阵列Co9S8/C/泡沫镍在0.2 A g-1电流密度下,第一次放电时展示出1926 mA h g-1的比容量,第一次充电时达1371 mA h g-1,并且历经200次循环过程后,可逆容量还维持1114 mA h g-1,体现出了非常好的电化学性能。不规则的小粒径颗粒表面可以提供更大的表面积用于锂离子的运输和储存,也能更好地适应充放电过程中的体积膨胀。同时,泡沫镍作为整个负极的集流体,可以在一定程度上增加材料的导电性,促进电子的运输和扩散,同时它疏松的大孔骨架可以有效保证活性物质与电解液的充分接触,利于离子和电子穿梭于正极和负极之间。
Abstract
li li zi dian chi de yi yu ji gao neng liang mi du 、gao dian ya 、gao shou ming deng zeng ge xing neng you shi ,yi jing zuo wei yi chong xin xing de ti dai xing neng yuan 。shi chang shang mu qian ying yong de fu ji cai liao zhu yao yi dan mo tan wei zhu ,ke shi you yu ji zi shen xing zhi de que xian ,yi jing bu neng man zu gao xiao li li zi dian chi bu duan zeng chang de xu qiu ,suo yi wo men ying gai xun zhao rong liang geng gao wen ding xing geng hao de fu ji cai liao shi li li zi dian chi de xing neng jin yi bu di sheng 。guo du jin shu lin hua wu 、liu hua wu ju you yuan gao yu dan mo tan de li lun rong liang 、ge kuo de dian ya ping tai he huan jing you hao xing ,shi fei chang li xiang de li li zi dian chi fu ji cai liao 。dan shi ,ji zi shen yi ran cun zai dian zi chuan dao xing bu zu 、chong fang dian guo cheng zhong hui chan sheng ti ji peng zhang deng wen ti ,zhe hui shi ta men de shi ji rong liang di yu li lun rong liang 。ben wen zhen dui guo du jin shu lin hua wu 、liu hua wu de zhe xie xing zhi que xian ,cai yong jian chan de ge cheng fang fa ,tong guo tan cai liao (ru tan na mi guan )de yuan wei sheng chang rang ji yu tan cai liao jin hang fu ge ,li yong shu song duo kong de jie gou te zheng he yuan wei sheng chang de tan na mi guan di gao cai liao de dian zi chuan dao xing bing ju tong guo dui kang ti ji bian hua ying li lai yao shu huo xing wu zhi de jie gou bian xing ,jin er di gao cai liao de dian hua xue xing neng 。zhu yao de yan jiu jie guo zong jie ru xia :1、tong guo zi cui hua de fang fa zai gao wen chang shi jian duan shao de tiao jian xia shi ZIF-67zhong de jin shu li zi zuo wei cui hua ji ,shi you ji pei ti zai xing cheng tan kuang jia de tong shi zai biao mian yuan wei cui hua sheng cheng zhi jing yao wei 3 nmde tan na mi guan ,zai tong guo jin yi bu de lin hua guo cheng ,xing cheng le tan na mi guan jiao zhi de duo kong CoP@N-(C/CNTs)。dui ji jin hang dian chi xing neng ce shi hou ,fa xian dang dian liu mi du wei 0.5 Ag-1shi ,ta shou ci fang /chong dian bi rong liang fen bie wei 1215 mAh g-1/688 mA h g-1,bing ju zai li jing 200ci xun huan hou bao liu 600 mA h g-1de ke ni rong liang ,zhe shi you yu cai liao de duo kong jie gou neng gou jian qing li li zi qian ru /tuo chu guo cheng zhong de ying li xing bian ,bao chi jie gou wen ding ,yuan wei sheng chang de tan na mi guan ke yi wei li zi he dian zi de zhuai yi di gong geng duo de tong dao he lu jing ,di gao cai liao de dian zi chuan dao xing 。zhe chong yuan wei sheng chang de tan na mi guan ge cheng fang fa jian chan ,zhi bei de fu ge cai liao xing neng you yi ,zheng ming le zhe chong zi cui hua xing cheng tan na mi guan jiao zhi wang lao shi yi chong fei chang jian bian you xiao de jie gou she ji ce lve 。2、li yong Ni-MOFzuo wei yuan shi cai liao ,zai di wen de tiao jian xia tong guo jian chan de liang bu duan shao bu zhou ,sheng cheng le duo kong tan qiu nei bao guo jin shu ke li bing zai qiu ti biao mian yuan wei yan shen chu tan na mi guan de na mi jie gou ,zai tong guo jin yi bu de lin hua zui zhong xing cheng Ni2P@C/CNTs。Ni2Pna mi ke li bei hen hao de bao guo zai shu song duo kong de tan qiu nei ,ke yi huan jie Ni2Pzuo wei fu ji huo xing cai liao zai dian chi xun huan fang dian he chong dian de guo cheng zhong de ti ji bian hua he jie gou bian xing ,duo kong de jie gou di gao le jie gou wen ding xing ;tan qiu biao mian sheng chang de tan na mi guan wei li zi /dian zi de yi dong di gong le geng duo de lu jing ,zeng jiang le cai liao de dian zi chuan dao xing 。Ni2P@C/CNTscai liao zuo wei li li zi dian chi fu ji cai liao shi ,zai 0.2 Ag-1de dian liu mi du xia ,di yi ci fang dian /chong dian bi rong liang wei 652 mAh g-1/443 mAh g-1,zai 300ci xun huan hou ke ni rong liang yi ran bao chi 442 mA h g-1,ti xian chu le fei chang hao de dian hua xue wen ding xing 。zhe chong zhi bei Ni2P@C-CNTde fang fa bu xu yao gao wen duan shao de tiao jian jiu ke yi yuan wei sheng cheng tan na mi guan ,jian chan fang bian ju jing ji huan bao ,dui tan na mi guan yu jin shu hua ge wu de fu ge you yi ding de jie jian yi yi 。3、yi pao mo nie zuo wei mo nian ge ji fu ji de ji liu ti ,zai shang mian fu zai ZIF-67,zai yi ZIF-67/pao mo nie zuo wei qian qu ti tong guo rong ji re fan ying jiang ZIF-67liu hua hou zai jin yi bu tan hua ,de dao le duo ceng na mi ke li zhen lie de Co9S8/C/pao mo nie fu ji cai liao 。zai dui ji jin hang dian hua xue xing neng ce shi hou ,duo ceng na mi ke li zhen lie Co9S8/C/pao mo nie zai 0.2 A g-1dian liu mi du xia ,di yi ci fang dian shi zhan shi chu 1926 mA h g-1de bi rong liang ,di yi ci chong dian shi da 1371 mA h g-1,bing ju li jing 200ci xun huan guo cheng hou ,ke ni rong liang hai wei chi 1114 mA h g-1,ti xian chu le fei chang hao de dian hua xue xing neng 。bu gui ze de xiao li jing ke li biao mian ke yi di gong geng da de biao mian ji yong yu li li zi de yun shu he chu cun ,ye neng geng hao de kuo ying chong fang dian guo cheng zhong de ti ji peng zhang 。tong shi ,pao mo nie zuo wei zheng ge fu ji de ji liu ti ,ke yi zai yi ding cheng du shang zeng jia cai liao de dao dian xing ,cu jin dian zi de yun shu he kuo san ,tong shi ta shu song de da kong gu jia ke yi you xiao bao zheng huo xing wu zhi yu dian jie ye de chong fen jie chu ,li yu li zi he dian zi chuan suo yu zheng ji he fu ji zhi jian 。
论文参考文献
论文详细介绍
论文作者分别是来自安徽大学的许江琳,发表于刊物安徽大学2019-07-03论文,是一篇关于过渡金属磷化物论文,过渡金属硫化物论文,碳纳米管论文,负极材料论文,锂离子电池论文,安徽大学2019-07-03论文的文章。本文可供学术参考使用,各位学者可以免费参考阅读下载,文章观点不代表本站观点,资料来自安徽大学2019-07-03论文网站,若本站收录的文献无意侵犯了您的著作版权,请联系我们删除。
标签:过渡金属磷化物论文; 过渡金属硫化物论文; 碳纳米管论文; 负极材料论文; 锂离子电池论文; 安徽大学2019-07-03论文;