Confined NaAlH4 nanoparticles inside CeO2 hollow nanotubes towards enhanced hydrogen storage
Confined NaAlH4 nanoparticles inside CeO2 hollow nanotubes towards enhanced hydrogen storage
复制标题
将 NaAlH4 纳米颗粒限制在 CeO2 空心纳米管内，以增强储氢能力
DOI：
10.1039/c7nr03512h
复制
发表时间：
2017-10-14
期刊：
影响因子：
6.7
通讯作者：
Yu, Xuebin
中科院分区：
文献类型：
--
作者：
Gao, Qili;Xia, Guanglin;Yu, Xuebin
NaAlH4因其良好的热力学和较高的能量密度而被广泛认为是一种潜在的储氢材料。然而，较高的活化能垒和较高的脱氢温度严重阻碍了它的实际应用。本文采用一种简单的电纺法制备CeO2空心纳米管(HNTs)作为功能支架来负载NaAlH4纳米颗粒(NPs)，以提高其储氢性能。在高压下将熔融的NaAlH4渗透到CeO2 HNTs中制备的CeO2 HNTs中的纳米限制NaAlH4，与块体和球磨CeO2 HNTs催化的NaAlH4相比，表现出显著的脱氢性能。NaAlH4@CeO2复合材料的起始脱氢温度降至100℃以下，只有一个主脱氢峰出现在130℃，比块体材料和球磨CeO2 HNTs催化的NaAlH4分别低120℃和50℃。在180℃下，30min内氢气的释放量接近5.09wt%，而相同条件下球磨NaAlH4的氢气脱附率仅为1.6wt%。这一显著的改善主要归功于CeO2 HNTs的协同效应，它不仅可以作为结构支架来制备和限制NaAlH4纳米粒子，而且还可以作为有效的催化剂来提高NaAlH4的储氢性能。
NaAlH4 has been widely regarded as a potential hydrogen storage material due to its favorable thermodynamics and high energy density. The high activation energy barrier and high dehydrogenation temperature, however, significantly hinder its practical application. In this paper, CeO2 hollow nanotubes (HNTs) prepared by a simple electrospinning technique are adopted as functional scaffolds to support NaAlH4 nanoparticles (NPs) towards advanced hydrogen storage performance. The nanoconfined NaAlH4 inside CeO2 HNTs, synthesized via the infiltration of molten NaAlH4 into the CeO2 HNTs under high hydrogen pressure, exhibited significantly improved dehydrogenation properties compared with both bulk and ballmilled CeO2 HNTs-catalyzed NaAlH4. The onset dehydrogenation temperature of the NaAlH4@CeO2 composite was reduced to below 100 degrees C, with only one main dehydrogenation peak appearing at 130 degrees C, which is 120 degrees C and 50 degrees C lower than for its bulk counterpart and for the ball-milled CeO2 HNTs-catalyzed NaAlH4, respectively. Moreover, similar to 5.09 wt% hydrogen could be released within 30 min at 180 degrees C, while only 1.6 wt% hydrogen was desorbed from the ball-milled NaAlH4 under the same conditions. This significant improvement is mainly attributed to the synergistic effects contributed by the CeO2 HNTs, which could act as not only a structural scaffold to fabricate and confine the NaAlH4 NPs, but also as an effective catalyst to enhance the hydrogen storage performance of NaAlH4.