有機電化學電晶體因具備低操作電壓、高跨導以及優異的離子－電子耦合特性，近年來在生物電子元件、類神經運算及感測應用等領域受到廣泛關注。然而，對於N型有機混合離子－電子導體而言，離子注入所導致的薄膜膨潤與結構劣化仍是限制元件長期穩定性的主要挑戰。因此，本研究設計並合成一系列以萘二甲醯亞胺為核心之 N 型共軛高分子 P1–P4，藉由系統性調控主鏈中噻吩單元含量與骨架規則性，探討其對有機電化學電晶體性能之影響，並進一步與聚乙二醇進行混摻，以提升材料的離子傳輸能力。研究結果顯示，在所有材料中，聚乙二醇混摻之 P2 系統展現最均衡的元件表現，其體積電容達 43.1 F cm⁻³、電子遷移率為 5.40 × 10⁻³ cm² V⁻¹ s⁻¹，且經 80 次操作循環後仍可維持約 75% 的初始汲極電流。結構分析進一步指出，P2 在離子注入過程中雖產生明顯的層狀間距擴張，但具有良好的可逆性，其值由 22.9 Å 增加至 24.9 Å；中子反射分析結果亦顯示其在去摻雜後能夠恢復原有結構。相較之下，骨架規則性較低或共軛長度過長之材料，則分別呈現電子傳輸效率下降或操作穩定性受損的現象。綜合上述結果，本研究證實適當調控高分子骨架剛性、結構規則性以及離子可及形貌，對於兼顧電荷傳輸能力與電化學穩定性具有關鍵影響，並可作為未來高性能N型有機電化學電晶體材料設計的重要依據。

Organic electrochemical transistors have attracted considerable attention for bioelectronics, neuromorphic computing, and sensing applications. However, swelling and structural degradation caused by ion uptake remain major challenges for n-type organic mixed ionic-electronic conductors. Therefore, a series of n-type naphthalene diimide-based conjugated polymers, P1 to P4, with systematically varied thiophene contents and backbone regularity, was developed and blended with polyethylene glycol to investigate the structural factors governing organic electrochemical transistor performance. Among the investigated materials, the polyethylene glycol-blended P2 system exhibited the most balanced characteristics (volumetric capacitance of 43.1 F cm⁻³, an electron mobility of 5.40 × 10⁻³ cm² V⁻¹ s⁻¹, and retaining approximately 75% of its initial drain current after 80 cycles). Structural analyses further showed that P2 underwent pronounced yet reversible lamellar expansion during ion injection (lamellar spacing increasing from 22.9 to 24.9 Å upon doping, while neutron reflectivity results revealed substantial recovery after dedoping. In contrast, polymers with lower backbone regularity or excessive conjugation length exhibited either reduced electronic transport efficiency or compromised operational stability. This work demonstrates that optimizing backbone rigidity, structural regularity, and ion-accessible morphology is essential for balancing charge transport and electrochemical stability, providing molecular design guidelines for high-performance n-type organic electrochemical transistor materials.

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