CAJ | 학술논문

二氧化钛(TiO2)作为有前景的钠离子电池负极材料,具有良好的循环稳定性,但由于其导电率较低,而导致容量和倍率性能不佳限制了其实际应用.本文采用喷雾干燥技术制备了氧化石墨烯/纳米TiO2复合材料(GO/TiO2),通过热处理获得还原氧化石墨烯/TiO2复合材料(RGO/TiO2).电化学测试结果表明,还原氧化石墨烯改性的RGO/TiO2复合材料的电化学性能得到显著提升, RGO含量为4.0%(w)的RGO/TiO2复合材料在各种电流密度下的可逆容量分别为183.7 mAh?g-1(20 mA?g-1),153.7 mAh?g-1(100 mA?g-1)和114.4 mAh?g-1(600 mA?g-1),而纯TiO2的比容量仅为93.6 mAh?g-1(20 mA?g-1),69.6 mAh?g-1(100 mA?g-1)和26.5 mAh?g-1(600 mA?g-1).4.0%(w) RGO/TiO2复合材料体现了良好的循环稳定性,在100 mA?g-1电流密度下充放电循环350个周期后,比容量仍然保持146.7 mAh?g-1.同等条件下,纯TiO2电极比容量只有68.8 mAh?g-1. RGO包覆改性极大提高了TiO2在钠离子电池中的电化学嵌钠/脱钠性能. RGO包覆改性技术在改进钠离子电池材料性能中将有很好的应用前景.
이양화태(TiO2)작위유전경적납리자전지부겁재료,구유량호적순배은정성,단유우기도전솔교저,이도치용량화배솔성능불가한제료기실제응용.본문채용분무간조기술제비료양화석묵희/납미TiO2복합재료(GO/TiO2),통과열처리획득환원양화석묵희/TiO2복합재료(RGO/TiO2).전화학측시결과표명,환원양화석묵희개성적RGO/TiO2복합재료적전화학성능득도현저제승, RGO함량위4.0%(w)적RGO/TiO2복합재료재각충전류밀도하적가역용량분별위183.7 mAh?g-1(20 mA?g-1),153.7 mAh?g-1(100 mA?g-1)화114.4 mAh?g-1(600 mA?g-1),이순TiO2적비용량부위93.6 mAh?g-1(20 mA?g-1),69.6 mAh?g-1(100 mA?g-1)화26.5 mAh?g-1(600 mA?g-1).4.0%(w) RGO/TiO2복합재료체현료량호적순배은정성,재100 mA?g-1전류밀도하충방전순배350개주기후,비용량잉연보지146.7 mAh?g-1.동등조건하,순TiO2전겁비용량지유68.8 mAh?g-1. RGO포복개성겁대제고료TiO2재납리자전지중적전화학감납/탈납성능. RGO포복개성기술재개진납리자전지재료성능중장유흔호적응용전경.
Anatase TiO2 shows excel ent long-term cycling stability as an anode for sodium-ion batteries. However, the low specific capacity and poor rate capability resulting from its intrinsic low electrical conductivity limit its applications. In this work, TiO2 nanoparticles were coated with reduced graphene oxide (RGO) using a combination of spray-drying and heat treatment. Electrochemical tests showed that the obtained RGO/TiO2 composites had improved electrochemical performances. The reversible capacities of the RGO/TiO2 [4.0%(w)] composites were 183.7 mAh?g-1 (20 mA?g-1), 153.7 mAh?g-1 (100 mA?g-1), and 114.4 mAh?g-1 (600 mA?g-1). Bare TiO2 showed low capacities of 93.6 mAh?g-1 (20 mA?g-1), 69.6 mAh?g-1 (100 mA?g-1), and 26.5 mAh?g-1 (600 mA?g-1). The 4.0%(w) TiO2/RGO composites exhibited good cycling stability with a charge capacity of 146.7 mAh?g-1 at a current density of 100 mA?g-1 after 350 cycles, compared with 68.8 mAh?g-1 for bare TiO2. RGO modification is a promising method for improving the electrochemical performances of the sodium energy-storage materials.