以原子層沉積法製備奈米鉑觸媒於氮化鈦反蛋白石結構應用於質子交換膜燃料電池之研究

Fabrication of Pt Catalyst on TiN Inverse Opal Structure for Proton Exchange Membrane Fuel Cell by Atomic Layer Deposition

劉又榮(Yoh-Rong Liu)

指導教授 ： 彭宗平

國立清華大學/工學院/材料科學工程學系/碩士(2014年)

https://doi.org/10.6843/NTHU.2014.00359

摘要

本論文主要係研究以原子層沉積技術 (atomic layer deposition, ALD) 製備氮化鈦 (TiN) 反蛋白石結構，作為鉑觸媒之支撐物，應用在質子交換膜燃料電池 (proton exchange membrane fuel cell, PEMFC)。利用旋轉塗佈法將不同直徑之聚苯乙烯 (PS) 球塗佈在碳紙上，製備多層聚苯乙烯球 (PS sphere multilayers)，做為反蛋白石結構模板，其表面積可藉由使用較小的球和增加層數來提升，而結構的孔隙也可藉由不同大小的球做調整。之後使用原子層沉積法將二氧化鈦沉積於多層聚苯乙烯球上，以製備二氧化鈦反蛋白石結構；再將其在氨氣氛圍下做氮化處理，發現可在800 ˚C持溫一小時得到完全之氮化鈦反蛋白石結構。再利用原子層沉積將沉積白金奈米顆粒於氮化鈦反蛋白石結構上，白金可均勻沉積在厚度為10 µm之氮化鈦載體上，其顆粒大小和重量也可由ALD之循環數決定。由於ALD自我侷限反應之特性，白金重量也可藉由使用尺寸較小的球及增加氮化鈦結構厚度而提升。燃料電池效率由自製的燃料電池測試平台量測，雖然自製電極之效能低於商用材，但在相同白金重量下，卻有較高的比效能和白金利用效率。

關鍵字

原子層沉積技術 ； 氮化鈦 ； 反蛋白石結構 ； 鉑觸媒 ； 質子交換膜燃料電池

並列摘要

Titanium nitride (TiN) inverse opal structure was fabricated by atomic layer deposition (ALD) as a support for Pt catalyst for proton exchange membrane fuel cell (PEMFC) by atomic layer deposition (ALD). Polystyrene (PS) spheres were coated in multilayers on carbon paper by spin-coating as a template. The surface area can be increased by using smaller size of spheres and by increasing the thickness of PS multilayers. The proportion of micropores can also be adjusted by using spheres in different diameters. Titanium dioxide (TiO2) thin film was then deposited on PS sphere multilayers by ALD. Titanium nitride inverse opal structure was obtained by direct nitridation of TiO2 inverse opal structure in flowing ammonia atmosphere at 800 ˚C for 1 h. Platinum nanoparticles were then deposited on TiN inverse opal structure by ALD as well, and a uniform coverage down to 10 µm of depth was achieved. The particle size and loading could be controlled by the cycle number of ALD. Because of self-limiting reactions of ALD, the Pt loading can be increased by lowering the sphere size and increasing the thickness of TiN inverse opal layers. The performance of PEMFC using Pt/TiN inverse opals as electrodes was evaluated by a home-made PEMFC test station. The home-made electrodes showed lower power capacities but showed higher specific power densities and thus better utilization efficiency of Pt compared with that using commercial E-Tek electrodes.

並列關鍵字

atomic layer deposition ； titanium nitride ； inverse opal structure ； Pt catalyst ； proton exchange membrane fuel cell

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