使用高分子有機矽化合物作為前驅物所衍生出的陶瓷材料SiOC在近10年來備受關注，其作為鋰離子電池的負極材料可相對於傳統使用的石墨(372 mAh/g)提供更高的電容量密度，且相對於矽基負極材料來得結構穩定體積膨脹率低，但其結構內部的自由碳量是有限的且結晶與非結晶的比例不易改變，會影響其導電度與電容量密度，因此如何控制其生成的量與比例是值得研究的方向。
本論文研究使用急速升降溫熱解製程方法，高分子前驅物選擇成本低且取得容易的商業化矽油類原料，分別是Dow Corning SylgardTM 184矽橡膠A劑與B劑以及虎王中性矽利康填縫劑，透過添加適當的交聯劑進行改質，尋找最佳的添加比例與交聯溫度時間，其衍生出的SiOC負極材料在500 mA/g的電流密度下表現出最高可逆電容量約為900 mAh/g，並持續循環300圈以上。如此優秀的電性表現要歸功於此材料內的非結晶碳，其大量sp3鍵結使結構中產生許多空隙及微孔的缺陷，進而增加鋰離子的儲存空間。而剩餘的sp2部分就如同石墨穿插在其中負責導電，矽氧鍵主鏈則負責穩固結構，進而優化其循環壽命。藉由前驅物改質的方式控制內部的自由碳可進一步提升其電化學性能，使此材料更具有商業化之潛力。

Polymer derived silicon oxycarbide (SiOC) has gained lots of attentions for the past ten years because of its high capacity. This ceramic material can offer higher theoretical capacity density than conventional anode materials, graphite (372mAh/g).It also has better structural stability and lower volume expansion than silicon anode material. However, the total amount of free carbon domain in SiOC is limited and the ratio of disorder carbon phase is difficult to change. These two issues would have a great effect on conductivity and theoretical capacity density. It is worthy to research how to control free carbon in SiOC.
In this work, we use simple pyrolysis process (rapid thermal treatment) to produce SiOC anode material. Three cheap commercialized polymers were selected as the precursor: Dow Corning SylgardTM silicone elastomer 184 A/B and FUN WAN Neutral silicone sealant. By adding cross-linking agent and changing cross-linking ratio or temperature, we can get SiOC anode exhibited high reversible discharge capacity density around 900 mAh/g and remained at least 300 cycles at a current density of 500 mA/g. Its excellent performance was attributed to the free carbon phase which contained disordered carbon sp3 bonding leading to a lot amount of nanovoids. Thus, lithium atoms can be stored in more places. Besides, the sp2 graphite enhanced the conductivity, and the Si-O-C glass phase maintained the structure stability; therefore, enhanced the cycle retention. If we can control the free carbon in SiOC easily, it is possible that SiOC can be the next generation commercialized anode material.

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