因近年來市場上對於鋰離子電池更高能量密度的需求，在負極材料中，矽具有極高的理論電容量(3580 mAh g-1)，但因其在充放電過程中，會伴隨著巨大的體積變化，造成其初圈所形成的SEI膜不穩定，進而使其出現較低的庫倫效率與循環表現不佳的現象，故本研究透過將檸檬酸與抗壞血酸修飾於矽材表面，期望透過此兩種小分子能對矽材表面有更好的包覆性，並且形成較穩定的SEI膜。
將檸檬酸與抗壞血酸修飾於矽材表面的過程中可分成兩步驟，第一步是透過行星式球磨機將矽、抗壞血酸與檸檬酸進行混合，第二步則是藉由熱處理的方式使矽上的羥基與修飾分子上的羥基羧酸發生脫水反應形成鍵結，研究中主要探討熱處理溫度的改變對於修飾層之影響，並透過材料分析與電化學分析來對其進行深入探討。
本研究成功將檸檬酸與抗壞血酸修飾於矽活性材表面上，改善原始矽材前幾圈電容量大幅衰退的問題，並提升其循環穩定性。於材料分析中可觀察到隨著熱處理溫度越高，修飾層越薄，並當溫度高於300℃時，抗壞血酸會轉變成不利於形成穩定SEI膜的分子結構；電性分析中顯示M-Si 150℃經過100圈之充放電測試後，具有最佳的循環壽命表現，電容量為1787 mAh g-1；在快速2C充放電下，其同樣擁有最佳表現，電容量為593 mAh g-1。

We successfully modify citric acid and ascorbic acid on silicon surface via a simple planetary ball-milling and heat treatment without high cost and risk of environment pollutions. This study shows that heat treatment temperature significantly affect molecular structure in the modification layer and modification layer thickness. The observed electrochemical performance of M-Si 150℃ shows good cycling ability (1787 mAh g-1 with 75.8 % retention after 100 cycles). Thus, M-Si 150℃ as anode material performs better electrochemical properties.

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