纳米棒状LiV_(3)O_(8)电控离子交换选择性提锂的应用

Application of Electrochemically Switched Ion Exchange to the Extraction of Lithium ions with High Selectivity Using Nanorod LiV_(3)O_(8)

通过水热-固相两步法制备了纳米棒状钒酸锂(LiV_(3)O_(8)),采用XRD、FTIR、SEM、XPS等手段测试了LiV_(3)O_(8)的结构和形貌,并考察了不同煅烧温度下合成的LiV_(3)O_(8)的电控离子交换(ESIX)性能。实验结果表明,500℃煅烧得到的LiV_(3)O_(8)拥有均匀的纳米棒结构以及最佳的电化学性能;将其制备成电活性功能膜,采用电控离子交换技术在100 mg/L的锂溶液中对Li^(+)的吸附量可达36.36 mg/g.同时LiV_(3)O_(8)对锂离子具有高选择性及稳定性,在等摩尔Li^(+)、K^(+)、Mg^(2+)混合溶液中,Li^(+)/K^(+)和Li^(+)/Mg^(2+)的选择性因子分别达到38.43和4.75,经历5次循环后,锂离子的吸附容量仍可保持98.3%.

LiV_(3)O_(8) with nanorod structure was prepared by hydrothermal-solid method.In this work,the structure and morphology of LiV_(3)O_(8) were characterized by XRD,FTIR,SEM,XPS,etc.,and the electrochemically switched ion exchange(ESIX)performance of LiV_(3)O_(8) synthesized at different calcination temperatures was investigated.The experiment results show that LiV_(3)O_(8) calcined at 500℃had evenly nanorod morphological structure and the best electrochemical performance.The lithium ion adsorption capacity of LiV_(3)O_(8) film reached 36.36 mg/g at 100 mg/L Li^(+)solution by ESIX technology.Moreover,LiV_(3)O_(8) exhibited high selectivity and stability towards Li^(+).The selectivity factors of Li^(+)/K^(+)and Li^(+)/Mg^(2+)reached 38.43 and 4.75,respectively,when the initial molar ratios of Li^(+)/K^(+)/Mg^(2+)is 1∶1∶1.The lithium ion adsorption capaci-ty of LiV_(3)O_(8) film still maintained 98.3%of the initial value after 5 cycles.