Photoluminescence quenching of thermally treated waste-derived carbon dots for selective metal ion sensing | IDCSA, NCHU

Photoluminescence quenching of thermally treated waste-derived carbon dots for selective metal ion sensing 2021-03-16

Recycling Agriculture: Rising value of Agricultural Waste【Department of Environmental Engineering / Lin, Kun-Yirew / Distinguished Professor】
循環農業：農業廢棄物高價值化【環境工程學系/林坤儀特聘教授】

論文篇名	英文：Photoluminescence quenching of thermally treated waste-derived carbon dots for selective metal ion sensing 中文：用於選擇性金屬離子傳感的熱處理廢物衍生碳點的光致發光猝滅
期刊名稱	Environmental Research
發表年份,卷數,起迄頁數	2021, 197, 111008
作者	Hu, Chechia; Lin, Tzu-Jen; Huang, Ying-Chu; Chen, You-Yu; Wang, Ke-Hsuan; Lin, Kun-Yi Andrew(林坤儀)
DOI	10.1016/j.envres.2021.111008
中文摘要	在本研究中，碳點 (CDs) 來自農業廢物苦茶渣的熱氧化，以獲得不同的 sp²/sp³ 比率和用於金屬傳感的電子結構。在 700 °C 下煅燒獲得的 CD 在不同溫度下處理的所有樣品中表現出最高的光致發光 (PL) 量子產率 (QY)，為 11.8%。這些 CD 具有高度的石墨化，導致強烈的 π-π* 電子躍遷，因此具有高 QY。通過在 320 nm 激發波長下監測它們的 PL 強度，CD 的強光致發光可用於感應金屬離子 Ag⁺、Sr²⁺、Fe²⁺、Fe³⁺、Co²⁺、Ni²⁺、Cu²⁺ 和 Sn²⁺。金屬以Ag⁺>Fe²⁺、Fe³⁺、Ni²⁺>Sr²+、Co²⁺、Cu²⁺、Sn²⁺的順序抑制PL強度，這表明CDs表現出較高的金屬離子檢測能力和選擇性。使用 CD 檢測 Fe3+ 在 10-100 ppm 的範圍內進行，LOD（檢測限）值為 0.380 ppm。理論計算表明，Ag⁺、Sr²⁺ 和 Sn²⁺ 誘導了電荷轉移激發，而 Fe²⁺ 和 Ni²⁺ 通過與 sp² 簇的絡合誘導了 d-d 躍遷。電荷轉移激發和 d-d 躍遷阻礙了 sp² 簇的 π-π* 躍遷，導致猝滅效應。另一方面，Li⁺、Na⁺ 和 K⁺ 離子沒有改變 sp² 簇的 π-π* 躍遷，導致猝滅效應可以忽略不計。總之，可以定制源自苦茶渣的 CDs 的氧化水平和電子結構，並且 CDs 被證明是一種簡便、可持續且環保的金屬傳感材料。
英文摘要	In the present study, carbon-dots (CDs) were derived from the thermal oxidation of an agricultural waste, bitter tea residue, to obtain different sp²/sp³ ratios and electronic structures for metal sensing. The CDs obtained from calcination at 700 °C exhibited the highest photoluminescence (PL) quantum yield (QY) of 11.8% among all the samples treated at different temperatures. These CDs had a high degree of graphitization, which resulted in a strong π-π* electron transition, and hence in a high QY. The strong photoluminescence of the CDs could be used to sense the metal ions Ag⁺, Sr²⁺, Fe²⁺, Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺, and Sn²⁺ by monitoring their PL intensity at an excitation wavelength of 320 nm. The metals inhibited the PL intensity in the order Ag⁺ > Fe²⁺, Fe³⁺, Ni²⁺ > Sr²⁺, Co²⁺, Cu²⁺, Sn²⁺, which demonstrated that the CDs exhibited high metal ion detection capability and selectivity. The detection of Fe³⁺ using CDs was performed in the range of 10–100 ppm with a LOD (limit of detection) value of 0.380 ppm. Theoretical calculations demonstrated that Ag⁺, Sr²⁺, and Sn²⁺ induced charge transfer excitation and that Fe²⁺ and Ni²⁺ induced d-d transitions via complexation with the sp² clusters. The charge transfer excitation and d-d transitions hindered the π-π* transition of the sp² clusters, leading to a quenching effect. On the other hand, Li⁺, Na⁺, and K⁺ ions did not alter the π-π* transition of the sp² clusters, resulting in a negligible quenching effect. In summary, the oxidation level and electronic structure of CDs derived from bitter tea residue could be tailored, and the CDs were shown to be a facile, sustainable, and eco-friendly material for metal sensing.
發表成果與本中心研究主題相關性	透過本研究可進一步建立開發本研究計算所需之觸媒材料，並釐清可適合應用之環境條件!