隨著資訊科技與人工智慧的快速發展，光電元件逐漸朝向多功能整合與低功耗方向演進。相較於傳統電控操作，光刺激操作具備非接觸式、低功耗及波長選擇性等優勢。此外，基於環境永續發展之需求，具可再生性與低毒性的天然生物材料亦逐漸被導入光電元件之研究中。本研究選用富含官能基且具優異成膜性與界面相容性的天然多醣材料—柑橘果膠（citrus pectin）作為功能性生物基質，分別結合氧化鎳（NiO）奈米顆粒與氧化鋅（ZnO）奈米棒，成功開發光控電阻式記憶體與紫外光感測器。
在光控電阻式記憶體方面，透過簡易製程將NiO奈米顆粒均勻分散於柑橘果膠中以形成複合薄膜。柑橘果膠具備良好的分散與封端能力，可有效結合NiO之豐富缺陷態以捕捉載子，進而實現紫外光寫入與電抹除的操作行為。所製備的元件展現良好的操作一致性與重複耐久性，且記憶保存時間可維持超過10⁴秒，顯示出穩定的非揮發特性。
另一方面，在紫外光感測器部分，柑橘果膠展現良好的結構導向能力，可有效調控ZnO奈米棒的結構成長並優化其缺陷分布。在365 nm紫外光照射下，所製備的元件其光暗電流比可達10⁴以上，響應度為6.6 A/W，且具備快速動態響應能力，其上升與下降時間分別為2.62秒與19.19秒，顯示優異的光感測性能。
綜合而言，本研究證實柑橘果膠與金屬氧化物感光材料 (氧化鎳與氧化鋅) 的結合擁有光電操作可行性，為發展多功能整合與永續的綠色光電元件提供一條具潛力的發展方向。

With the rapid advancement of information technology and artificial intelligence, optoelectronic devices are evolving toward multifunctional integration and low power consumption. Compared with traditional electrically controlled operation, light-stimulated operation offers the advantages of non-contact control, low power consumption, and wavelength selectivity. In addition, driven by the demand for environmental sustainability, natural biomaterials with renewability and low toxicity are increasingly being introduced into optoelectronic device research. In this study, citrus pectin—a natural polysaccharide rich in functional groups and possessing excellent film-forming properties and interfacial compatibility—was selected as a functional bio-based matrix. By combining it with nickel oxide (NiO) nanoparticles and zinc oxide (ZnO) nanorods, light-controlled resistive random-access memory (RRAM) and ultraviolet photodetectors were successfully developed.
For the light-controlled RRAM, NiO nanoparticles were uniformly dispersed in citrus pectin through a simple process to form a composite thin film. Citrus pectin exhibited excellent dispersion and capping ability, effectively integrating with the abundant defect states of NiO to trap carriers. This enabled light-writing under ultraviolet illumination and electrical erasing operations. The fabricated device demonstrated good operational uniformity, cyclic endurance, and stable non-volatility, with a data retention time exceeding 10⁴ seconds.
On the other hand, in the UV senosr, citrus pectin served as an effective structure-directing agent, successfully regulating the growth behavior of ZnO nanorods and optimizing their defect distribution. Under 365 nm UV illumination, the device achieved a photocurrent-to-dark current ratio of over 10⁴, a responsivity of 6.6 A/W, and fast dynamic response with rise and fall times of 2.62 s and 19.19 s, respectively, demonstrating excellent photosensing performance.
In summary, this study confirms the feasibility of combining citrus pectin with metal oxide photosensitive materials (NiO and ZnO) to achieve photo-induced operation. The results provide a promising pathway for the development of multifunctional, integrated, and sustainable green optoelectronic devices.

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