應用g-C3N4光催化降解氮氧化物之研究

Photodegradation of Nitrogen oxide by g-C3N4 and g-C3N4 coated Fiber Glass

王佳蓉(Lkhagvajargal Ganzorig)

指導教授 ： 王雅玢

共同指導教授 ： 游勝傑(Sheng-Jie You)

中原大學/工學院/環境工程學系/碩士(2021年)

https://doi.org/10.6840/cycu202100801

摘要

光催化氧化 (PCO) 是一個對室內及室外環境空氣污染物進行降解的先進技術。而光催化亦是一種有助於環境改善的技術，用於淨化空氣污染物改善空氣品質。由於汽機車等不同空氣污染來源向環境中排放過多的氮氧化物，室外空氣品質逐漸惡化，g-C3N4是一種新興的氮氧化物降解光催化劑。由於其獨特的性質，被廣泛用於光催化活性。本研究的主要目的是研究用於氮氧化物降解的高效光催化劑和有效輻照。以熱分解方法製備 g-C3N4，該方法被稱為一步合成法，在不添加其他試劑的情況下提高對氮氧化物的光催化性能。首先，以製備好的 g-C3N4作為原料，並對其以及塗有玻璃纖維之 g-C3N4，以實驗室規模之反應器中進行太陽光和可見光下光催化劑的講解效率研究。其中本研究亦針對其他影響氮氧化物光催化效率性能的參數，如使用量、濕度、輻照度、氮氧化物濃度和流量。透過XRD、DRS、FTIR、BET、ESR、XPS、EPR 和 TEM等特徵分析，在催化劑表面上的g-C3N4具有奈米柱，提高了 g-C3N4 和 g-C3N4@玻璃纖維在太陽光和可見光的光催化效率，且進行了有效的氧化還原反應，使氮氧化物的最終濃度迅速降低。g-C3N4對太陽光和可見光的降解效率分別為86.1%以及77.4%，而g-C3N4@玻璃纖維對太陽光和可見光的降解效率分別為99.8%以及99.9%。在經過5個循環後，光催化劑在可見光以及紫外光的效率降低4.1%以及3.2%。

關鍵字

光催化劑 ； 修復 ； 改善 ； 輻照 ； 熱分解

並列摘要

Photocatalytic oxidation (PCO) is an advanced technology operating to degrade the air pollutants from the indoor and outdoor environment. Photocatalysis is also an environmental remediation technology used to decontamination of air pollutants to improve air quality. Air quality is degrading daily due to the excessive amount of NOx emissions into the environment from different sources such as motor vehicles. G-C3N4 is an emerging photocatalyst for NOx degradation. Due to its unique properties, it is widely used in photocatalytic activities. In this study, g-C3N4 was prepared by thermal decomposition called the one-step synthesis method to enhance the photocatalytic performance over NOx without adding any other agent. First, prepared g-C3N4 was used as raw material. The g-C3N4, and g-C3N4, coated with glass fiber used as a photocatalyst in the lab-scale reactor under solar light and visible light. The influencing parameters in the photocatalytic activity of NOx, such as amount, humidity, irradiation, NOx concentration, and flow rate, were also studied, affecting the catalyst's performance. By the characterization XRD, DRS, FTIR, BET, ESR, XPS, EPR and TEM, it has been proved that g-C3N4 has Nano-rods on the surface of the catalyst, which enhances the photocatalytic activity of g-C3N4 and g-C3N4@fiber glass over solar and visible light and performed an effective redox reaction by which the final concentration of NOx decreasing rapidly. The degradation efficiencies of g-C3N4 over solar and visible light are 86.1%, 77.4% respectively, while g-C3N4@fiber glass over solar and visible light is 99.8%, 99.9% respectively. In addition after 5 cycles, the photocatalyst reuse rate decreased by 4.1% under solar light and 3.2% under visible light.

並列關鍵字

Photocatalyst ； Remediation ； Air quality ； Irradiation ； Thermal decomposition

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