Mechanisms of Co, Ni, and Mn based water splitting catalysts probed by advanced EPR spectroscopy

凭借化学系化学催化项目的这一奖项，R。来自加州大学戴维斯分校的大卫布里特将研究一种有效的太阳能水分解催化剂，该催化剂将作为清洁可再生能源技术的基础，产生氢气，氢气可以储存，然后在燃料电池中再氧化发电，或用作形成液体燃料的还原中间体。 这些研究是基于Kanan和Nocera的发现，即中性磷酸盐缓冲液中的钴（II）在极化电极表面上自发形成水裂解催化剂。 布里特实验室将使用多频EPR光谱来研究这种钴催化剂的结构细节及其分解水的机制。 将使用CalEPR实验室的连续波（CW）和脉冲EPR仪器，频率范围为8至130 GHz，以及佛罗里达NHMFL的高频仪器。 多频EPR将用于研究钴催化剂的几何和电子结构。 脉冲双共振实验（ENDOR，ESEEM和HYSCORE）将探测钴离子上的未成对电子与磁核（如钴（59），氧（17）和磷（31））的相互作用，并将结果与已知结构的模型钴络合物进行比较。 对硼酸镍类似物的新研究将补充钴膜研究，在Nafion膜中形成的锰催化剂的额外工作将有助于在这些自组装无机催化剂和重要的光系统II Mn氧释放复合物之间建立桥梁。了解氢气产生的细节对于能源产生至关重要，并且重要的是激发学生对可再生能源和环境的兴趣。问题. 每年PI教授一个荣誉一般化学序列，所涵盖的主题;电化学，过渡金属配位化学，化学动力学和光谱学，非常适合直接将讲座与目前在合成和生物系统中无机方法水分解和太阳能燃料的研究联系起来。 PI将把这个研究项目的各个方面融入到讲座中。 PI计划招募几名一年级学生在夏天在实验室研究这些主题。 此外，他还教授一门高年级的仪器分析课程，这将为本科生介绍电子顺磁共振（EPR）技术和能源研究提供进一步的机会。 他的研究小组还参与了该部门新的NSF-REU计划，该计划强调能源。

With this award from the Chemical Catalysis Program of the Division of Chemistry, Professor R. David Britt from the University of California at Davis will study an efficient solar water splitting catalysis that would serve as the basis of a clean renewable energy technology, producing hydrogen gas, which could be stored and then reoxidized to generate electricity in a fuel cell, or used as a reductive intermediate in forming a liquid fuel. The studies are based on the discovery by Kanan and Nocera that cobalt(II) in neutral phosphate buffer spontaneously forms a water splitting catalyst on a polarized electrode surface. The Britt laboratory will use multifrequency EPR spectroscopy to investigate details of the structure of this cobalt catalyst and the mechanism by which it splits water. Continous wave (CW) and pulsed EPR instruments of the CalEPR laboratory will be used, over a frequency range from 8 to 130 GHz, as well as higher frequency instruments at the NHMFL in Florida. Multifrequency EPR will be used to examine the geometric and electronic structure of the cobalt catalyst. Pulsed double resonance experiments (ENDOR, ESEEM, and HYSCORE) will be probing the interaction of unpaired electrons on the cobalt ions with magnetic nuclei such as cobalt(59), oxygen(17), and phosphorus(31), and the results will be compared with model cobalt complexes of known structure. New studies on nickel borate analogues will be complementing the cobalt film studies, and additional work on a manganese catalyst formed in a Nafion membrane will help in bridging between these self assembled inorganic catalysts and the important Photosystem II Mn oxygen evolving complex.Understanding the details of the production of hydrogen gas is essential for energy generation and it is important to motivate students on renewable energy and environmental issues. Every year the PI teaches an honors general chemistry sequence, and the topics covered; electrochemistry, transition metal coordination chemistry, chemical kinetics, and spectroscopy, are ideally suited to tie lectures directly to current research in inorganic approaches to water splitting and solar fuels, in both synthetic and biological systems. The PI will integrate aspects of this research project into the lectures. The PI plans to recruit several first year students to work in the laboratory on these topics over the summer. In addition, he is teaching an upper division instrumental analysis class, which will provide a further opportunity to introduce undergraduates to electron paramagnetic resonance (EPR) techniques and energy research. His research group is also participating in the department's new NSF-REU program, which has an energy emphasis.