氣相生成多功能與多尺度梯度材料之研究

Vapor-Phase Formation of Multifunctional Gradient Materials in Multiscale Regimes

徐耀宗(Yao-Tsung Hsu)

指導教授 ： 陳賢燁

國立臺灣大學/工學院/化學工程學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201901031

摘要

本研究基於模擬自然界中濃度梯度所驅動之質量傳遞的機制，開發了一種可精確控制材料尺度的多功能梯度材料制程方法。研究中，我們利用在瞬態質量傳輸機制內具有的時間/位置關係與該過程獨特的昇華/沈積過程，成功在厘米、毫米和微米之範圍內產生梯度，並製備出該尺度下的梯度材料。利用具有揮發性的乙醇所產生的梯度，可以導致最終產物中產生孔隙度梯度，以達到孔洞梯度材料的製備。另外，使用不同功能性的分子，可以創造出具備不同功用的梯度材料。例如，使用非揮發性物質Fe3O4 和PEDOT 導電高分子（聚-3,4-乙烯二氧噻吩）所形成反向梯度，可以形成一具有的磁性能力（由Fe3O4 提供）和電化學反應性（由PEDOT 提供）之多功能梯度材料。

關鍵字

梯度 ； 昇華與沉積 ； 孔洞材料 ； 多功能性 ； 尺度控制

並列摘要

An elegant and precise method of manufacturing gradient materials was developed based on a mechanism mimicking molecular mass transport driven by concentration gradients found in nature; in addition, this process took place during a unique vapor sublimation and deposition process. With time-dependent control within a transient mass transport regime, gradients were produced at the centimeter, millimeter, and micrometer range. The versatility of the method was demonstrated by choosing a variety of (functional) molecules for the production of gradients, and a controlled volatility gradient of ethanol was used to result in a porosity gradient in the final product. Nonvolatile molecules were shown to localize Fe3O4 and PEDOT conductive polymer (poly-3,4-ethylenedioxythiophene), forming a counter-current configuration and resulting in synergistic and multi-functional gradients in magnetic properties (Fe3O4) and electrochemical conductivity (PEDOT) within the same created material.

並列關鍵字

gradient ； sublimation and deposition ； porous material ； multifunctionality ； scale control

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