过渡金属硼酸盐具有成本低、环保友好、电压极化低和氧化还原电位合适等优点,是一种极具应用前景的新兴材料。硼原子与氧原子的键合可以形成具有高电负性位点的阴离子(如BO33-、BO45-和BO69-),这些阴离子可以与过渡金属阳离子键合,使得过渡金属硼酸盐具有不同的结构。尽管一些过渡金属硼酸盐表现出比相应的过渡金属氧化物更优越的初始库仑效率(ICE),但它们在基于碳酸酯电解液的钠离子电池中具有较差的倍率性能和循环寿命,阻碍了其实际应用。
基于此,四川大学高分子科学与工程学院王延青特聘研究员课题组,在材料领域知名期刊Advanced Science上发表题为“Combustion activation induced solid-state synthesis for N, B co-doped carbon/zinc borate anode with a boosting of sodium storage performance”的研究论文。
Figure 1. Na+ storage mechanism and rate performance of CBZG anode.
本文要点
要点一:基于插层诱导燃烧活化法合成了N、 B共掺杂碳/硼酸锌(CBZG)
Figure 2. a) Illustration of the synthesis process for CBZG. TG curves of b) the mixture of Zn(NO3)2·6H2O and glycine, c) H3BO3, and d) the mixture of Zn(NO3)2·6H2O, glycine and H3BO3.
要点二: CBZG的形貌结构
Figure 3. Structure and morphology of the obtained materials. a) XRD patterns of BZ, CBZ, and CBZG. b) SEM image of CBZG. c) Element mapping images of CBZG. d) TEM image of CBZG. e, f) High-resolution TEM images of CBZG.
要点三: CBZG在醚/酯基电解液中的钠离子电池性能
Figure 4. Na+ storage performance of CBZG as the half-cell anode in ether- or ester-based electrolyte. a, b) CV curves at 0.2 mV s-1. c) Discharge/charge profiles at 0.05 A g-1. d) Rate capability. e) Comparison between CBZG anode and previously reported SIB anodes in capacity. Cycling performance at f) 2 A g-1 and g) 10 A g-1.
要点四: CBZG在醚/酯基电解液中的储钠机理
Zn6O(OH)(BO3)3+Na++e-?3ZnO+Zn3B2O6+NaBO2+0.5H2①
Zn3B2O6+6Na++6e-?3Zn+3Na2O+B2O3②
反应①在醚基电解液中不可逆,而在酯基电解液中可逆。
Figure 5. Na+ storage process analysis of CBZG as the half-cell anode in ether- or ester-based electrolyte. Discharge/charge profiles at 0.05 A g-1 and ex situ XRD patterns under various stages in a) ether-based electrolyte and b) ester-based electrolyte.
要点五: CBZG在醚/酯基电解液中的动力学过程
Figure 6. Kinetics analysis of Na+ storage of CBZG anode in ether- or ester-based electrolyte. a, b) CV curves at different scan rates. c) b-value calculation. d, e) Capacitive contributions at 1.0 mV s-1. f) Capacitive contributions at different scan rates. g) GITT potential profiles with a pulse current of 0.05 A g-1 for 0.5 h, followed by a 1.0 h relaxation process. h) Na+ diffusion coefficients calculated from the GITT potential profiles for the discharge process. i) Nyquist plots.
文章链接:Combustion activation induced solid-state synthesis for N, B co-doped carbon/zinc borate anode with a boosting of sodium storage performance
DOI:10.1002/advs.202207751
http://doi.org/10.1002/advs.202207751
通讯作者简介
王延青博士,男,四川大学特聘研究员,四川省“海外高层次人才引进计划”特聘专家,国家制革技术研究推广中心特聘专家,四川省专家服务团专家,日本政府高端引进外国人(日本高度人才1号)。入选四川大学“双百人才工程”计划(2019-2023),日本学术振兴会(JSPS)外国人特别研究员(2015-2017)。2019年加入四川大学高分子科学与工程学院高材系独立开展研究工作,成立先进碳与能源材料应用研究室。主要从事超长碳纳米管的单分散原理、碳基材料的设计制备及其在能源、环境相关领域的应用研究,主要包括:超长碳纳米管在非/弱极性有机体系的分散研究、新型高倍率快充锂电池导电剂、低温锂电池负极、钠电池硬碳负极、电磁屏蔽/吸波材料、超级电容器、碳基导热/散热材料、柔性显示材料、先进高分子功能材料等,在Advanced Science(2篇),Carbon(8篇),Chemical Engineering Journal,Small,J Mater Chem A,Energy Storage Materials等高水平学术期刊上发表论文40余篇。研究成果获得了山东省科技进步一等奖、国家优秀自费留学生奖学金、中国专利优秀奖、山东省专利奖、四川省特聘专家、JSPS外国青年学者研究奖励、北海道大学私费外国人留学生特待制度、四川大学优秀科技人才奖、盐都特聘专家等。