EPR Spectroscopy of the Cobalt Water Splitting Catalyst

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。这项研究奖在无机，生物无机和有机化学计划支持教授R。大卫布里特在加州戴维斯大学进行基础研究的结构和机械细节的水分裂由一个简单的钴催化剂。麻省理工学院的研究人员最近证明，中性磷酸盐缓冲液中的Co（II）在极化的电极表面上自发地形成水分解催化剂。 这种催化剂提供良好的电流密度，自组装和自修复，在环境条件下在中性pH水中以低过电位运行，并且由廉价的地球丰富的材料形成。 该研究计划长期以来一直专注于光合作用中水分解的电子顺磁共振（EPR）研究，其中采用了天然锰簇，该研究计划现在正在使用相同的EPR方法来详细研究钴催化剂。该研究计划正在检查电化学产生的钴催化剂的几何和电子结构。 各种EPR技术将探测钴离子上的未成对电子与钴、磷酸盐和水的磁性核的相互作用。该研究计划是进行原位电化学和快速冷冻淬火，以捕获催化剂在氧释放周转，并使用同样先进的EPR技术来探讨催化机理。学生们对可再生能源和环境问题非常感兴趣。 两名无机化学研究生正在进行这项计划的研究。这个无机水分解计划的主题完美地融入了PI在加州大学戴维斯分校教授的荣誉一般化学序列。PI在讲座中不断强调正在进行的光合作用和钴及相关合成络合物的放氧复合物科学的相关性。一些本科生将在暑期对该项目进行研究。对新型钴催化剂的EPR研究将为这个简单系统的工作原理提供新的见解，从而指出改进的方向。鉴于我们对清洁和碳中和的可再生能源的迫切需求，开发高效的太阳能水分解催化剂将成为清洁可再生能源技术的基础。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). This research award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports work by Professor R. David Britt at the University of California Davis to carry out fundamental research on structural and mechanistic details of water splitting by a simple cobalt catalyst. Investigators at MIT recently demonstrated that Co(II) in neutral phosphate buffer spontaneously forms a water splitting catalyst on a polarized electrode surface. This catalysis provides good current density, self assembles and self repairs, operates at low overpotential in neutral pH water under ambient conditions, and forms from cheap, earth-abundant materials. The research program has long focused on electron paramagnetic resonance (EPR) studies of water splitting in photosynthesis, where a natural manganese cluster is employed, and the research program is now using the same EPR methods to examine the cobalt catalyst in detail. The research program is examining the geometric and electronic structure of the cobalt catalyst as electrochemically generated. Various EPR techniques will probe the interaction of unpaired electrons on the cobalt ions with magnetic nuclei of cobalt, phosphate, and water. The research program is carrying out in situ electrochemistry and rapid freeze quenching to trap the catalyst during oxygen evolving turnover, and use the same advanced EPR techniques to probe the catalytic mechanism.Students are very motivated by renewable energy and environmental issues. Two Inorganic Chemistry graduate students are conducting research in this program. The topics of this inorganic water splitting program integrate perfectly into the honors general chemistry sequence that the PI is teaching at UC Davis. The PI continually emphasizes the relevance of the ongoing science of the oxygen evolving complex of photosynthesis and of the cobalt and related synthetic complexes in lectures. Some undergraduates will do research on the project during the summer.The EPR studies on the new cobalt catalyst will provide new insights into how this simple system works and thereby indicate directions for its improvement. Given our crucial needs for clean and carbon-neutral renewable energy, the development of efficient solar water splitting catalysts would serve as the basis of a clean renewable energy technology.