Mir Ab Qayoom, Dolui Dependu, Khandelwal Shikha, Bhatt Harshil, Kumari Beena, Barman Sanmitra, Kanvah Sriram, Dutta Arnab
Chemistry Discipline, Indian Institute of Technology Gandhinagar.
Chemistry Department, Uka Tarsadia University.
J Vis Exp. 2019 Oct 5(152). doi: 10.3791/60231.
Developing photocatalytic H2 production devices is the one of the key steps for constructing a global H2-based renewable energy infrastructure. A number of photoactive assemblies have emerged where a photosensitizer and cobaloxime-based H2 production catalysts work in tandem to convert light energy into the H-H chemical bonds. However, the long-term instability of these assemblies and the need for hazardous proton sources have limited their usage. Here, in this work, we have integrated a stilbene-based organic dye into the periphery of a cobaloxime core via a distinct axial pyridine linkage. This strategy allowed us to develop a photosensitizer-catalyst hybrid structure with the same molecular framework. In this article, we have explained the detailed procedure of the synthesis of this hybrid molecule in addition to its comprehensive chemical characterization. The structural and optical studies have exhibited an intense electronic interaction between the cobaloxime core and the organic photosensitizer. The cobaloxime was active for H2 production even in the presence of water as the proton source. Here, we have developed a simple airtight system connected with an online H2 detector for the investigation of the photocatalytic activity by this hybrid complex. This photosensitizer-catalyst dyad present in the experimental setup continuously produced H2 once it was exposed in the natural sunlight. This photocatalytic H2 production by the hybrid complex was observed in aqueous/organic mixture media in the presence of a sacrificial electron donor under complete aerobic conditions. Thus, this photocatalysis measurement system along with the photosensitizer-catalyst dyad provide valuable insight for the development of next generation photocatalytic H2 production devices.
开发光催化制氢装置是构建全球基于氢气的可再生能源基础设施的关键步骤之一。已经出现了许多光活性组件，其中光敏剂和基于钴肟的制氢催化剂协同工作，将光能转化为H-H化学键。然而，这些组件的长期不稳定性以及对危险质子源的需求限制了它们的使用。在此工作中，我们通过独特的轴向吡啶键将基于芪的有机染料整合到钴肟核心的外围。这种策略使我们能够开发出具有相同分子框架的光敏剂-催化剂杂化结构。在本文中，我们除了对这种杂化分子进行全面的化学表征外，还解释了其合成的详细过程。结构和光学研究表明钴肟核心与有机光敏剂之间存在强烈的电子相互作用。即使在以水作为质子源的情况下，钴肟也对制氢具有活性。在此，我们开发了一种与在线氢气探测器相连的简单气密系统，用于研究这种杂化配合物的光催化活性。实验装置中存在的这种光敏剂-催化剂二元体系一旦暴露在自然阳光下就会持续产生氢气。在完全有氧条件下，在牺牲电子供体存在的情况下，在水/有机混合介质中观察到了这种杂化配合物的光催化制氢。因此，这种光催化测量系统以及光敏剂-催化剂二元体系为下一代光催化制氢装置的开发提供了有价值的见解。
