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以硝酸镧、硝酸锶、硝酸锰为原料,采用超声波辅助溶胶-凝胶法制备了纳米钙钛矿La_(1-x)Sr_xMnO_3(x=0、0.1、0.2、0.3、0.4、0.5),并与石墨烯进行了掺杂改性。利用XRD、SEM-EDS和DLS对La_(1-x)Sr_xMnO_3及石墨烯/La_(1-x)Sr_xMnO_3复合材料进行结构表征,考察了煅烧温度、p H值对La_(1-x)Sr_xMnO_3晶型和尺寸的影响,并测试了石墨烯改性对复合材料性能的影响。结果表明:超声波辅助条件下,650℃、p H=10时制备的La_(1-x)Sr_xMnO_3分散性良好、粒径均匀,平均粒径为210 nm。XRD结果表明:石墨烯掺杂未改变La_(1-x)Sr_xMnO_3晶相。首次充放电实验结果表明:与改性前相比,石墨烯掺杂改性后复合材料作为催化剂的锂空气电池,首次放电容量从4 300 m Ah/g升高至7 900 m Ah/g。
La_ (1-x) Sr_xMnO_3 (x = 0,0.1,0.2,0.3,0.4,0.5) nanocopper was prepared by ultrasonic assisted sol-gel method using lanthanum nitrate, strontium nitrate and manganese nitrate as raw materials Doped with graphene modified. The structure of La1-x SrxMnO3 and graphene / La1-x SrxMnO3 composites were characterized by XRD, SEM-EDS and DLS. The effects of calcination temperature and p H value on the crystal structure of La1-x SrxMnO3 Type and size, and tested the effect of graphene modification on the properties of the composites. The results show that La_ (1-x) Sr_xMnO_3 prepared at 650 ℃ and pH = 10 has good dispersibility and uniform particle size with an average particle diameter of 210 nm under ultrasonic wave. XRD results show that: graphene doping did not change the La_ (1-x) Sr_xMnO_3 crystal phase. The results of the first charge and discharge experiments show that the initial discharge capacity of the lithium-air battery doped with graphene-doped composite increases from 4 300 m Ah / g to 7 900 m Ah / g compared with that before modification.