在科技的快速發展以及電動車的普及下，以鋰離子電池為基礎發展的儲能系統也
必須具有更高的能量密度與功率密度以達到應用需求，為了達成此目的，高電位的正
極材料成為一發展的方向，而橄欖石結構的高電位正極材料為目前潛在可運用的材料
之一，其中的鋰鎳磷氧(LiNiPO4,LNP)正極材料具有較高的電位與電容量，但是現階
段對於此材料的特性討論並不充足，因此本研究利用 DFT 第一原理計算方法，透過
建立 LNP 表面重構模型，進行表面能的計算以及 Wulff shape 的建立發現 LNP (010)
與(201)表面在(010),(201),(101),(100),(011)五個低指數表面中具有較低的表面能，同時
也為 LNP 顆粒平衡時最容易裸露在外的兩個表面，並且態密度分析顯示(011)面相較
其他表面具有較低的能隙。
而後以第一原理分子動力學方法建立非晶碳層模型並修飾於 LNP 正極表面建立
LNP/C 系統，計算後發現 LNP 僅有(010)表面氧的位置(site1,site3)傾向與碳層做吸附，
且吸附過程為一化學吸附並具熱力學穩定性，同時非晶碳層吸附只會影響吸附界面處
的電荷密度，並不影響 LNP 正極內部的電荷分佈，吸附界面處則以碳氧間原子作用
力為主。
在態密度分析下非晶碳層的修飾會使 LNP(010)表面的費米能階產生表面碳層 p
軌域的 state 使其整體導電特提升，並且透過建立 88%與 29%鋰含量的充電模型，以
熱力學計算探討 LNP 與 LNP/C 系統鋰遷出的容易程度發現在初始與深度充電的情形
下，非晶碳層修飾皆有助於鋰由 LNP 正極表面遷出，而鋰由次表面遷出至表面的趨
勢則會隨非晶碳層結構不同而改變。

In this study, the surface properties of the high potential olivine cathode LNP was
studied and a model of carbon layer modification was successfully developed to observe the effect of amorphous carbon layer modification on the LNP cathode by first-principles calculation.

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