In situ,Real-time Environmental SEM Imaging System Development for Water Splitting Reaction Using a Dynamic Light Illumination System
In situ,Real-time Environmental SEM Imaging System Development for Water Splitting Reaction Using a Dynamic Light Illumination System
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使用动态光照明系统开发水分解反应的原位实时环境 SEM 成像系统
DOI：
10.1017/s143192761600492x
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发表时间：
2016
影响因子：
2.8
通讯作者：
K. Suganuma
中科院分区：
文献类型：
--
作者：
T. Daio;I. Narita;T. Gondo;K. Suganuma
光催化在水裂解制氢反应中起着至关重要的作用，特别是作为催化剂可以减少污染。到目前为止，这种催化行为已经通过数学方法进行了研究，并通过计算机模拟在纳米尺度上进行了设计。虽然活性位点的测定对于改善催化功能是重要的，但是由于电子显微镜内的真空条件，很少进行活性位点的直接观察，例如电子显微镜，需要液体、光和气氛的动态可控性的原位观察催化行为仍然具有挑战性。因此，人们希望开发一种新的电子显微镜，其中我们可以改变环境下的光照与大气压力。为了实现环境的电子显微镜（EM）的观察，气体注入系统，封闭的细胞系统和倒置显微镜开放样品室与膜支持已经开发[1]，[2]。关于液体中的电子显微镜，已经证明了封闭环境单元系统，例如利用石墨烯和MEMS（微机电系统）封闭单元[3]。首先，在液体中的原位观察需要固体膜以防止液体沸腾。除了使用开放式空气室进行操作的优势外，恶劣的表面条件需要一个封闭的系统来保持样品处于非反应性气体中。因此，需要一种能够按需动态改变环境的封闭单元系统。特别是对于水裂解材料，催化剂的苛刻表面条件需要非活性气体/液体封闭。为此，我们首次研制了封闭回路动态气液交换系统。此外，首次将光照明系统集成到气/液池系统中。
Photocatalysis plays a crucial role in water splitting reaction to generate the hydrogen, and particularly as catalysis which can reduce contamination. To date, this catalytic behavior has been studied by mathematical approaches and designed by computer simulation at the nanoscale. Although the determination of the active site is important to improve the catalytic function, direct observation of activity sites eg electron microscope has rarely been performed because of the vacuum conditions inside an electron microscope, in situ observation of photocatalysis behavior which requires liquid, light and dynamic controllability of the atmosphere still remains challenging. Therefore, it is desirable to develop a new electron microscopy in which we can change the environment under illumination of light with atmospheric pressure.To achieve environmental observations in an electron microscope (EM), a gas injection system, closed cell system and an inverted microscopy open specimen chamber with membrane support have been developed [1],[2]. Regarding electron microscopy in liquid, a closed environmental cell system has been demonstrated eg utilizing graphene and a MEMS (Micro Electro Mechanical Systems) enclosed cell [3]. First, in situ observation in liquid requires a solid membrane to prevent from the liquid boiling. Besides its advantage of hands on operation by using open air chamber; severe surface conditions require an enclosable system to keep the specimen into non-reactive gas. Thus, a closed cell system which can dynamically change environment on demand is desired. Especially, as for the case of water splitting material, severe surface condition of catalyst requires the non-active gas/liquid enclosure. Thus, we first developed the dynamic gas-liquid exchanging system with enclosed circuit. Furthermore, light illumination system is integrated to the gas/liquid cell system for the first time.