多孔壁碳纳米笼负载钯纳米颗粒的研究
关键词：碳纳米笼；钯纳米颗粒；比表面积
Abstract
Hydrogen peroxide widely used in the industry is an important inorganic chemical product. Palladium is usually used as a catalyst in hydrogen peroxide preparation. However, there are a series of problems, which should be solved before the kind catalyst is widely applied, such as low stability, low resistance of corrosion, and low ductility. Here, the methods for loading Pd nanoparticles on C support have been investigated to release those problems. For comparison, two loading methods (reduction via route and macerating) and two different supports (VCX-72 and carbon nanocages) are involved. As a result, wet-chemical deposition is more effective route than macerating for Pd loading, because this method decreases reduction rate of Pd and a controllable reduction processing leads to smaller sizes of Pd nanoparticles and high specific surface area as well. Compared with VCX-72, carbon nanocages perform better, as Pd support materials, due to their high specific surface area. When Pd loading amount is the same, there are more nucleation points for Pd deposition and high surface area also improve distribution of Pd nanoparticles on the nanocage surface, leading to improvement of Pd Loading.
Keyword: Carbon nanocages; Palladium nanoparticles; Specific surface area
目录
摘 要 1
第一章 绪论 2
1.1 双氧水研究背景 2
1.2 本课题研究目的和意义 8
第二章 实验过程 11
2.1 实验设备以及原料 11
2.1.1 实验原料 11
2.1.2 实验设备 11
2.2 实验过程 12
2.2.1多孔壁碳纳米笼的制备 12
2.2.2浸渍法制备钯-碳复合材料 12
2.2.3液相还原发制备Pd/VCX72复合材料 13
2.2.4液相还原法制备钯-碳纳米笼复合材料 13
2.3 样品表征 14
第三章 结果与讨论 16
3.1 原始样品表样分析 16
3.2 实验的XRD分析 17
3.2.1 实验结果的XRD分析 17
3.2.2 不同实验方法实验结果的XRD分析 19
3.3 XRD分析小结 23
3.4 碳纳米笼液相沉积法实验结果的TEM观察 24
第四章 结论 26
参考文献 27
致谢 29
第一章 绪论
1.1 双氧水研究背景
过氧化氢(H2O2，别名双氧水) 是一种重要的化工产品，它是一种强氧化剂，其水溶液可作为氧化剂、漂白剂、脱氧剂、消毒剂，在纺织、化工、造纸、环保、 电子、食品卫生等领域得到广泛应用[1]。分子式H2O2，分子量34，纯过氧化氢为无色液体，性质与水相似，可与水以任何比例混溶[2]，密度1.438，熔点-89℃，沸点151.4℃，溶于水、醇和醚，性质极为稳定，遇光和热或有重金属和其它杂质，均能引起分解，同时放出氧和热。过氧化氢具有较强的氧化能力，它是一种合乎生态要求的强氧化剂，在有酸存在的条件下较稳定，过氧化氢有腐蚀性。高浓度的过氧化氢能使有机物燃烧，过氧化氢与二氧化锰相互作用，放出氧气，密闭条件下能引起爆炸[3]。因此双氧水要储存在阴凉清洁通风的库房内，库温不易超过30℃，蔽日光。