利用有機金屬骨架製備中空多面體金屬氧化物混摻還原氧化石墨烯之鋰離子電池應用

Abstract

氧化銅是近年來鋰離子電池中備受矚目的陽極材料，因為擁有高理論電容量(~670 mAhg-1)，成本低等優點，然而，在與鋰離子反應時會造成材料膨脹，而造成電池的負面的效果，以及低導電度的問題需要克服。 此研究中以兩階段燒結氧化石墨烯與有機金屬骨架化合物[Cu3(btc)2]n(btc = benzene-1,3,5-tricarboxylate)，製備中空多面體複合物 rGO-Cuox，將其應用在鋰離子電池上，並測試其電化學表現。在200 mAg-1電流密度下，rGO-Cuox第一圈電容量為662 mAhg-1，從第三圈開始，電容量隨循環圈數增加而增加，到達第220圈時，電容量逼近700 mAhg-1。在1000 mAg-1電流密度下，亦有類似之現象。與氧化石墨烯及[Cu3(btc)2]n有機金屬骨架化合物相比，此rGO-Cuox複合材料結構成功提升鋰離子電池之效能。Cupric oxide as anode for lithium ion batteries(LIB) has attracted much attention due to its high theoretical capacity(~670mAh g-1) and low cost. However, the disadvantages are poor electrical conductivity and large volume expansion during lithiation resulting in fast fading of the capacity of cupric oxide. In this study, we synthesized hollow polyhydron rGO-Cuox by two step sintering graphene oxide and metal-organic frameworks compound [Cu3(btc)2]n(btc = benzene-1,3,5-tricarboxylate). The obtained rGO-Cuox materials were used in a lithium-ion battery and tested the electrical performance. The first cycle capacity is 662 mAh g-1 at rate of 200mA g-1. From the third cycle, the capacity increased with cycle. The capacity is 700mAh g-1 at 220 cycle . Similar phenomenon appeared at rate of 1000mA g-1. Compare to graphene oxide and metal-organic frameworks compound, the rGO-Cuox composite material successfully improved the performance of lithium ion batteries.