以微波電漿火炬製備可見光化光觸媒之研究

Fabrication of Visible Light Photocatalyst Powders via Microwave Plasma Torch

林聖凱(Sheng-Kai Lin)

指導教授 ： 魏大欽

中原大學/工學院/化學工程研究所/碩士(2005年)

https://doi.org/10.6840/cycu200500573

摘要

二氧化鈦粉末為現今相當熱門的商品，且可供可見光催化之二氧化鈦粉末引起眾多學者投入心力研究。本研究以異丙醇鈦為前驅物，利用微波電漿火炬製備二氧化鈦粉末，爾後再應用鍛燒法與電漿法進行處理與改質，探討參數改變對銳鈦礦相結晶、比表面積與粉末型態、及化學組成之影響，並測試與探討其光催化的行為。
研究中發現以微波電漿火炬製備二氧化鈦粉末，銳鈦礦相比例嚴重的受前驅物流量所影響；而由化學結構分析中，也發現粉末中含有大量的C、H、O元素，部分形成TiOC鍵結，使得粉體具有可見光催化的特性。經過熱處理與氧氣電漿處理後的粉體，能有效的提升結晶程度與降低含碳量，但比表面積也下降許多。爲了增加光觸媒的應用層面，藉由氮原子的植入能有效的增加可見光催化效率，但植入的量要適中，在XPS分析上之N/Ti約為0.09時為最好。
經由分解亞甲基藍的測試發現，結晶程度、銳鈦礦相結晶比與比表面積影響紫外光分解速率最大；可見光分解速率除了上述影響因素外，還受粉末內的化學結構影響；在未受雜質植入的粉末，以熱處理500℃，可見光催化效果最好，分解速率約為商業化粉體的3~7倍。以氮原子為雜質，被植入的粉體都能有效的提升光催化活性，其中以直接N2/H2電漿處理成效最好。

關鍵字

可見光光觸媒 ； 二氧化鈦 ； 微波電漿火炬 ； 電漿改質

並列摘要

In this study, TiO2 powders were synthesized from titanium tetraisopropanol by microwave plasma torch. Calcination and plasma treatment was used to enhance the photocatalytic activity of TiO2 powders. The ultraviolet or visible light photocatalysis was studied by the decomposition of methylene blue.
The anatase contents of the as-grown powders are strongly influenced by the precursor flow rate. TiOC bonding on the surface of as-grown powder is speculated to induce the visible light photocatalytic activity. The calcination and O2 plasma treatment can increase the anatase content of the powders, but the specific surface area is reduced. To improve the visible light photocatalytic activity, TiO2 powders were treated by N2/H2 plasma to dope the nitrogen atoms. From the XPS analysis, the TiO2 powders that contain N/Ti ratio of about 0.09 has the highest visible light photocatalytic activity.
Form the results of methylene blue decomposition, the photocatalytic activity was seriously influenced by the crystallinity, anatase content, and specific surface area of the powders. Besides, the visible light photocatalytic activity was also influenced by the chemical structure of the powders.

並列關鍵字

Plasma modification ； Titanium dioxide ； Visible light Photocatalyst ； Microwave plasma torch

參考文獻

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